I wanted to write a little on test cables in general, more specifically about the actual quality of the cables available at the lower end of the consumer market. Highlighting the prevalence of these types of cables, including the products that they tend to accompany. I also intend to instruct briefly how the end user can test these cables and how they can create their own superior home-made versions.
Low-end retail cables for test equipment
In my opinion low quality cables are especially evident in instances where the cables come bundled in with many lower-end chinese consumer test devices, as opposed to purchased separately. This is especially true in cases where the product is unbranded. Think cheap test equipment such as: £10 multimeters, or £50 bench power-supplies. For example the probe cables that come with the DT-830 multimeter.
To clarify I am not talking about genuinely dangerous or illegal (according to british safety law) cables, just low quality ones. Things such as chinese power cables that do not comply with the british safety standards – which are genuinely hazardous to the user and not fit for purpose; are outside the scope of this article. Genuinely dangerous cables like that run the risk of being confiscated at customs. I wrote an article on such a cable; it was a non-compliant BS1363. Link below. No, I am specifically talking about cables such as the ones on multimeter probes, and on bench top power-supplies. Inoffensive dreck.
Example of low quality cables bundled with multimeter
What factors dictate a cables quality?
Many times low quality wires will have a noticeable resistance value across them. This is often due to the cost cutting measures of the manufacturers. These include constructing items with lax specifications (quality control), or by saving on materials used. For example by minimising the number of actual strands of the copper conductors present within the cable, or by opting for a cheaper material substitute such as aluminium.
These cables being built to such a restrictive price-point: is what makes them very flimsy, basically disposable in many cases. Many of these types of cables are in my opinion, are merely designed to just tick the “comes with accessories” box in a products’ marketing materials.
This unfortunately makes the cable virtually without genuine use outside of the specific one that it was manufactured for. Often not even that use-case for long, due to their general fragility. So if you have some of these low quality cables in use. It may benefit you to replace them as soon as convenient; as they may be hampering your devices’ ability to perform.
For example, cheaper multimeters such as the previously mentioned DT-830 or the XL830L, are generally rather accurate. Often staying within a less than 2% error deviation from each other. However any variable resistances across their probes’ cables may affect their readings. They may for example: cause a notable voltage drop when in use, or affect the threshold for a continuity test.
A good example of a low quality cable would be: a power-supply cable that I got with my chinese bench-top power-supply. An unbranded QW-MS305D. By the by, it was actually the same unit that came with the non-compliant BS1363 plug. Never-the-less, the power-supply’s cable in question was used to power devices under test with DC voltages; as such they contain a male banana jack on one end and a crocodile clip on the other.
Although it is a relatively cheap power-supply, it could still reliably output it’s rated 30 volts at 5 amps. The only issue with the out-of-box setup (minus the bad plug), was that the output cable heated up and often got soft when exposed to the higher amperages that the power-supply could output. Although it took sometime for this to happen, i.e. it needed continuous output over several minutes. I still judge the cable as unsuitable for purpose. One thing I found humorous after the fact is that the online seller that I bought from had this same accessory packaged with the 10 amp version of this power-supply as well (QW-MS3010D).
Example of low quality cables that came with the power-supply
10 amp PSU
Using salvaged materials to create custom cables
As a response to the performance of the bought cable, I retired it. I removed the cable ends and attached them to a salvaged mains cable; and it has worked fine since. I really like using salvaged mains cables for these types of applications. Especially ones from UK safety certified devices; and especially ones from heating units. Such as electric room heaters, or toasters, electric grills, kettles, etcetera. Basically anything that uses electricity to generate resistive heat. This is because their cables are specced to allow large amounts of current to pass through them without heating up themselves.
For example: a typical mains oil heater, is rated for 1500 watts. This means that it’s cables need to safely pass that amount of power across them concurrently while the device is in use. When converted to volts and amperes; this means that these cables are able to handle 240 volts AC at 6.25 amps. This leaves me confident that it can safely handle the maximum 5 amps, 30 volts DC of my power-supply over long periods of time.
They do this by having very little resistance across the cable length. This is accomplished by actually putting copper in your copper cables. Although after looking at the example photos that I have, it appears that this particular cable is actually using aluminium strands as conductors.;) However the point stands; there are sufficient conductors within the cable, that the current can pass across it unhindered. I.e. The cable is of a big enough gauge, not to bottleneck the higher currents.
One thing to pay attention to when creating your own cables beyond the quality of the cable itself; is how you connect the various plugs you wish to use to it. This is because a poor connection here can impede the passage of electricity; and add resistance to the line. I suggest firm connections with as much conductive surface area touching as practical. It is also good form to do a resistance test across the entire thing once completed.
Another good source for quality salvaged cabling, is old or damaged ethernet cables. The twisted pairs within work very well in lower voltage DC applications; including carrying signal voltages (like binary data). The pair windings are configured to minimising interference for their carried digital signals after-all.
I like to use them to make home-made breadboard jumper cables. This can be done by just unwinding a length of cabling, cutting to size, then tinning the ends so that they can interface with the breadboard. Will it pretty? probably not. Will it be functional? 100%.
You could also use ethernet cables for replacing a cable between an external DC power-supply (or power-brick) and it’s paired device (e.g. Laptop). I tend to opt to wind together a pair of cables, if I wish to reliably carry current at higher DC voltages (e.g. 20VDC @ 3A for a laptop). However any higher than that and you’d be better served by using thicker gauge wires.
Home-made custom cable for power supply
Example of resistance test used to determine cable quality
Closing thoughts
That’s all really. I just wished to highlight that some low end cables are not good, and to encourage you to create your own superior cables using parts from common household devices.
QR codes are a type of barcode. Barcodes are a visual representation of digital (or binary) information. They are designed to be easily understandable by machines. Barcodes enable machines to do useful operations that involve interacting with the physical objects, that the barcodes are placed on. Such as sorting or counting large volumes of items accurately. For example, with packages at a mail depot, or product inventory at an automated warehouse or factory.
A QR code (or Quick Response Code), is a type of 2 dimensional barcode, otherwise known as a matrix barcode. All this means is that it represents it’s binary information visually across two axis (x and y). It does this by plotting black (1) and white (0) squares on a grid. Matrix barcodes are an evolution on the iconic one dimensional barcodes; which represent their binary information in a single array of black lines and white spaces (i.e. columns), that denote their ones and zeros respectively.
It should be noted that there are numerous different types of barcodes (both 1D and 2D) in use today. Each one is specialised to their specific applications. These specialisations manifest themselves with variations in visual design (e.g. with markers for orienting scanners with different protocols); barcode size, reflecting how much data they need to represent/encode; and data encoding ability; i.e. what type of data the barcode image represents (typically: numbers, or ASCII symbols).
The most obvious difference between one dimensional (array) and two dimensional (matrix) barcodes, is the addition of a Y dimension of information. This addition allows for a greater density of information to be stored, however it also requires more sophisticated tooling to actually read the data from the barcodes themselves. The most notable hardware difference in this regard is that one dimensional barcodes use a simple laser line scanner, whereas matrix barcodes require a camera module. Because of this, you typically can not read any matrix barcodes with hardware designed for 1D barcodes, however in many cases (providing that the software allows for it), you can use a matrix barcode scanner (e.g. smart phone) to read information from 1D barcodes.
Additionally, I make assumption that on a barcode: black denotes a one in binary and white a zero. Whereas in reality, it really doesn’t matter. This is because the interpretation of the barcode is all up to the protocol standard that it is using. For example with the case of a UPC-A type barcode, where it uses a 7 bit array to denote numbers. Different value bit arrays can symbolise the same (base 10) number depending on it’s location on the barcode.
UPC-A barcode image taken from wikipedia.org
table taken from wikipedia.orgExample of a 1D barcode in use as store’s inventory identifier
Consumer uses for QR Codes
I’ll limit this discussion to consumer use cases and applications because industrial applications are rather dry. They use QR codes in the same way they use other barcodes. Which is to orientate machines that operate with and around physical goods. This could include use cases such as at an Amazon sorting depot, barcodes are used to inform the sorting machines of what goods are in what shelves.
Where as within the consumer space; most QR codes in the wild, are simply used as a means of storing website links and affiliate information. These are designed to allow people to simply scan the code out of a magazine, business card, coupon, or what-have-you; in order to very quickly load the website hyperlink and/or fill a virtual document.
For example, a QR code at a public WIFI access point will have all the data necessary (link to login page, SSID, password) to allow the scanning smartphone to access their network. Likewise a QR code on a coupon will link to the retailer’s online store page and pass any promotional offers associated with that coupon automatically to it’s e-shop.
QR codes, at least when dealing within the consumer space, are predominantly a means of convenience. They reduce the friction encountered when user’s operate within virtual spaces. Friction such as inputting long arbitrary names or numbers (such as a WIFI network’s SSID or password); or website domain names, where a typo could expose the user to a potentially malicious imitator website.
The friction is reduced because the process of scanning a code with a modern smartphone is far easier, than inputting the data manually using (most likely) a touch keyboard into that same smartphone. Another benefit is the probability of user error (such as mistyping a password or domain name) is eliminated. This is done by automating the process of data entry and bypassing the user in that work flow. That’s what I believe constitutes the vast majority of useful applications of QR codes in the consumer space, at least this is the case when talking strictly about static QR codes.
Additionally. The Wikipedia article for QR codes list many different (specific) use cases for them in the the consumer space; however in my opinion they all boil down to the two things I mentioned earlier: following links and filling in virtual documents.
Anatomy of QR codes
The smallest unit of information on a QR code is referred to as a module. A module is a single square that is coloured either white or black. For example a version 1 QR code is made up of a 21 by 21 module grid, totalling 441 individual modules. If you were to count all the chequered squares along either axis, it will add up to 21.
Look at the below two examples, both of these QR codes are identical Version 1 QR codes. They both have the same 441 distinct modules on a 21 x 21 grid. The only difference is the actual image size. This should illustrate that (within reason) the actual pixel (or print) size of the modules doesn’t matter with QR codes. As long as the scanning devices’ cameras can fit the entire code structure within frame and focus.
A QR codes’ modules are organised into several structures. These include: three position markers, several alignment markers (number varies with version/size), a version information zone, a format information zone, a timing zone, an area for data and error correction keys, and finally a blank quiet zone to denote the border of a QR code.
image taken from wikipedia.org
QR code size specification
QR codes are rather versatile, they have the ability to encode: ASCII symbols (letters and numbers), media (images, sound, and video), as well as even executable programs (compiled binaries). However, although they technically have this capability, it is severely hampered by the size limitations of the QR code standard.
At the time of writing, the largest viable QR code that can be created is the ‘Version 40’ variant. QR code Version 40 can encode up to: 7089 bytes of pure numerics, 4296 bytes of alphanumerics, 2953 bytes of miscellaneous binary (e.g. media), or 1817 bytes of Japanese Kanji characters. This is done using the lowest value (level L) of error correction, thus leaving more space for actual data. So these are the absolute maximum values.
Refer to file “QRcode_version_table” below for a full list of all version specifications.
This was an interesting one, because although the version 40 QR code specification states that I could create a numerical QR code with a capacity of 7089 bytes. In actuality the maximum amount of data that I managed to fit into a QR code was 7080 bytes. I honestly don’t know what to make of that. The ECC (level L) was supposed to be factored into the 7089 max value, i.e that is the maximum data storage in addition to the space that the error correction takes up. So it can’t be what’s limiting me from the max value. As to what is happening, I’m not sure. It could be anything, including a limitation of the program I used to create these codes (qrencode), or it could be some unknown setting, text file associated metadata, or even some unnoticed human error in play. Hence I will include the input files I used here so that you can try it out yourself, and see where I messed up.
qrencode -r pi_decimals_7081.txt -o qrc_pi_7081.png
Failed to encode the input data: Input data too large
qrencode -r pi_decimals_7080.txt -o qrc_pi_7080.png
Successfully compiled QR code containing 7080 bytes of pure numbers
According to Xed, this file weighs 7080 bytes.
QR code Error Correction Capability
QR codes have a built in Error Correction Capability (ECC). They use the Reed-soloman error correction codes in order to facilitate a certain level of data redundancy. This enables QR codes to be readable even after they have sustained damage. Such as by getting scratched or being partially obscured by grime. This error correction facility comes in four levels: L, M, Q, and H. The error correction of each level is expressed as a percentage of the total data that can be lost whilst maintaining the QR codes readability.
This is as follows:
L has up to a 7% ECC
M has up to a 15% ECC
Q has up to a 25% ECC
H has up to a 30% ECC
Generally speaking, the error correction capability of a QR code isn’t free. The higher levels take up more of the QR code’s finite available space, space that could otherwise be used to encode more of the actual substantive data itself. This trade off between useable storage space and data read reliability, means that QR codes with higher ECC tend to be used in environments where code damage is more likely; or in applications where the printed QR code itself is going to in active operation for a longer time period. Such being attached to warehouse racking to identify the specific shelf location and product contents to an automated sorter machine.
image taken from archive.org – qrcode.com page
How to spot the ECC level on a QR code
To work out what type of ECC level set on a QR code, look towards the “format information” zone to the right of the lower left position marker. Immediately after the single column of blank (white) modules of the position marker, at the bottom of the QR code and the module just above it. These two modules display what level of ECC is employed within the QR code.
Bash instructions:
qrencode -l L -o qrc_ECC_L.png 'ECC'
qrencode -l M -o qrc_ECC_M.png 'ECC'
qrencode -l Q -o qrc_ECC_Q.png 'ECC'
qrencode -l H -o qre_ECC_H.png 'ECC'
zbarimg *.png
Using ECC to incorporate logos into QR codes
When I looked into how people actually created the fancier QR codes; the ones’ that incorporate graphics such as text and logos. I was genuinely surprised at the crudity of the methodology. I thought that it may involve something akin to passing arguments to the QR code generator to re-route the data sectors around the graphic. Nope. It’s actually laughably simple. If you wish to incorporate graphics into your QR code, just crank up the ECC to max. Output the QR code. Then slap that graphic on top the QR code using some graphics manipulation software. In this case GIMP. Done. I mean it does the job. I just don’t like the idea of purposefully damaging data integrity.
Look at the below examples. Both of these QR codes hold the same data. This being a link to this website’s homepage. The size disparity between these two is caused by the additional error correction code added to the level H QR code. It caused it to jump up a couple of versions. I’m guessing that since my logo covers more than 7% of each of the QR codes, this is the reason why the level L QR code is no longer functional, whereas the level H QR code continues to function after the addition of the logo due to the logo covering less than the 30% of it’s maximum error correction capacity. This methodology seems rather crude, but it works.
Example of a real QR code that incorporates a logo
Encoding and decoding QR codes
There are numerous ways to generate your own QR codes. I’ll just mention a few to give you an idea of where to start.
Firstly, I should mention that there are paid services that allow customers to get custom QR codes. This includes things like “dynamic” QR codes, that can supposedly keep a tally of the number of times they have been scanned. However if you aren’t using them for professional applications. I generally wouldn’t recommend using paid services like these. This is a tinkerer’s blog after all. That being said, I mention them here just to make you aware of their existence.
All the tools that I mention from this point are free to use and readily available. If you are using a Linux based operating system, or virtual machine, or use bash in Windows. I recommend downloading and using two programs: “qrencode” and “zbar-tools”. Both are available in the Ubuntu main repository. This is actually what I primarily used to create and test all the codes in this article.
The zbar-tools toolkit comes with two relevant programs. zbarimg and zbarcam. zbarimg is used to scan local images of QR codes and can output that data either to standard output (usually the shell), or piped into a file. zbarcam has similar functionality, except it can use the computer’s camera to capture a QR code.
Alternatively, for quick QR code generation you could use an online website. I don’t want to recommend any for liability reasons, as there are lots of random websites that can do this. What I found interesting though is that the search engine duckduckgo.com actually can generate QR codes as well. I came across it rather by accident, as it returned QR codes with the search term data within it.
To use DDG to create a QR code, just type in “qrcode” followed by a space and then whatever textual data you want in it. I find this method rather novel, and probably good for simple quick and dirty codes. However it lacks the precision of functionality that a program like qrencode gives you. Such as the ability to specify the module size, and ECC level of the generated QR code; qrencode does this by passing arguments to the program.
TLDR
Tools to create QR codes
Linux: qrencode
websites: duckduckgo.com, etcetera
paid services for business including dynamic QR codes
Tools to decode/scan QR codes
android phone apps
(zbar-tools) zbarimg & zbarwebcam
Encoding and decoding binary QR codes
To encode a file (such as an image) into a QR code, you need to pass an additional option to qrencode. Use the -8 argument to specify 8 bit mode. You also need to use the -r option to specify a file input.
To decode a QR code image of a binary into a file. You have to pass the below options to zbarimg, to allow it to know that it is dealing with a binary file. Additionally you then need to pass the output from zbarimg into a file. Otherwise it’ll just output the data into standard output (i.e. the shell itself).
One thing to note. Versions of zbarimg (zbar-tools) older than version zbar-0.23.1 do not have the capability to decode binary files. Additionally, at the time of writing the version of zbar within the Ubuntu repository was zbar-0.23; an older version without the capacity to decode binaries.
Alternatively decoding a binary QR code without specifying the output format, or without piping the contents into a file; instead just letting it output into the shell: will cast the contents as ASCII text. Instead of a file it will output a string of nonsense characters. However the first couple of legible characters should consist of file metadata that can tell you what format the binary data is in. The below example is the same QR code as above but outputted as ASCII rather than as a binary.
QR codes are basically ubiquitous today. They are present everywhere. And applicable in many use cases ranging from anything; from storing simple web links, to gaming uses such as markers for augmented reality. I recently found a tiny one that was printed into the underside of my kettle. Why is it there? Just because. The point is that they are everywhere.
Additionally, the technology is exceptionally accessible. Having a surprisingly small learning curve. This coupled with the fact that quality creation tools (like qrencode) are freely available, means that if you for whatever reason would like to use a QR code within your work; there is little reason not to do so.
If I am perfectly honest however. I personally don’t see much actual utility for me other than inserting a QR code linking to my website, or email within a business card. Perhaps, even in printed articles – as a means of linking in additional online resources. It’ll certainly have a lower level of friction, than printed hyperlinks have.
If I’m honest. The main real appeal of this technology to me is the novelty of storing binary information within a printable medium. The fact that you can encode an actual binary (so long as it is smaller than 2.9kb) into a paper medium, is wondrous. Check the links below for a Youtube video of a person who encoded an entire executable game into a static QR code. Not a web link to game. The game itself. Imagine storing actual games, into a book. Tiny games, but still. Cool.
This will be the first in a series of articles on making crap from garbage. I intend to build on this initial car, by adding more functionality and complexity down the line later. The purpose of this series of articles is to illustrate how accessible our hobby actually is. All you really need is access to information, basic tools, and most importantly: a little motivation and imagination.
Basic drag racer toy car.
As you can probably tell from the pictures; this toy car once had additional components that I removed for this write up. These included: 4 LED “””head-lights””” (2 white, 2 red); a jumper cable and switch, to allow the motor to be run using only one of the batteries at a time (for a slower speed); and additional wiring to allow the motor to run in reverse. Essentially whatever bollocks I felt like lazily sticking into the thing.
This should however illustrate that you can keep adding complexity to the basic frame work … Yeah, that’s why I reused the same haggard little tupperware container with the two unused switches: to make a point. It wasn’t abject laziness at all. Nah.
One could even keep adding complexity and replacing components until a simple drag racer can turn into a self steering robot. This could be done by using ultrasonic sensors, microcontrollers, and servo motors just as an example. However the basic framework is a good starting point.
Toy demonstration
Making the thing.
Tools and materials.
So what do you need to make this masterpiece? A soldering iron will help but twisted wire connections and electrical tape will do. Work with whatever you have on hand. I’ll just list out what I used.
Tooling:
soldering iron
heat gun
DC power supply
multimeter
precision knife
Consumables:
electrical tape
heat shrink
hot glue
Materials:
wires
tupperware box
gears and wheels kit
switches
AA battery holder
AA batteries
rubber-band (elastic band)
3 volts DC motor
Build process.
Its largely self explanatory from looking at the pictures but I’ll give ya a quick write up if you insist on reading. Nerd. Anyway, get either a cheap wheels and gears kit (yes I am a hippo-crit) from an online store, or salvage wheels from broken toys if you have any, or use bottle caps even. You can even make decent wheels from either cardboard or by working random stiff plastic with a saw and a file.
Next, cut appropriate holes into the plastic box, sardine can, old butter tub, or whatever you’re calling a chassis. Then affix the motor into the chassis using hot-glue or tape. I wanted to use a belt driven system for no other reason than I wanted to use a belt driven system. So I used a couple of belt pulleys from the gear kit and a near dead elastic band as a drive belt. I know what you are thinking, and yes it is very unreliable.
If I were to redesign this for simplicity and reliably; I would just insert the motor directly into one of the rear wheels and power it that way. Better yet you can use two motors, one for each rear wheel. Anyway, next, throw in a switch, a useless fuse just for fun, and an occupied battery pack. Done. Enjoy.
The project is so simple it seems silly didactically going through every step of slapping it together. Just look at the pictures: yours should be like that but good. The point is to make it using the materials on hand. Improvise as a matter of course.
One thing that might be good to improvise on is by using a salvaged battery holder if you can not find one. I know not everyone has access to broken Poundland fairy lights. For example the motor here came from a cheap hand held fan. I could easily use it’s chassis moulded battery holder instead and just butcher it to fit. No worries.
To source the material I recommend a discount store like the aforementioned Poundland or the 99P shop. You could probably get all the materials for less than a fiver. And if you’re really on a budget, then I recommend the dumpster behind Poundland. Don’t ask me how I know.
Belt demonstration
Schematic
It’s not really necessary given the simplicity of the circuit. But I’ve included one never the less for the sake of completeness.
made with digikey.com/schemeit/
Circuit power use.
To satisfy some curiosity I decided to measure the power usage of the motor, and power delivery that the batteries can supply. I did it to give me an idea of how much power the batteries are able to provide, and how much of that available power the single motor uses. That way I’d know what’s limiting performance, should that become a concern. And it will once I decide to start adding components, such as additional motors.
Results:
Tested with a 6 Ampere max bench power supply against mismatched old batteries. Guess which performed better?
(BPS = Bench Power Supply) BPS powered Motor (spinning freely): 3V @ 0.25A (0.75 W) BPS powered Motor (jammed): 3V @ 2.71 (8.13 W) Battery powered Motor (spinning freely) #1: 3V @ 0.18A (0.54 W) Battery powered Motor (jammed) #1: 3V @ 2.02A (6.06 W) Battery powered Motor (spinning freely) #2: 3V @ 0.29A (0.87 W) Battery powered Motor (jammed) #2: 3V @ 0.70A (2.10 W)
My conclusion on the circuits power usage is that the junk batteries that I used for this application are not able to provide the maximum amount of current that the motor can use when spinning freely in the first test. And in the second test although the batteries performed nominally when free spinning, when the motor was jammed causing it to draw more current; the batteries failed to provide the needed current. So the batteries are the limiting factor here. Probably because they’re dying. From this slapdash test, I can tentatively conclude that if I wanted to add an additional motor, I’d also need to scale the power supply relatively … or use new batteries.
Really I should’ve tested it with two fresh 1.5 volt alkaline batteries as a control. Then I could’ve tested the motor, by adding an additional two fresh 1.5 volt batteries (in 3 volt series) parallel with the base two, to allow for a higher circuit current output without increasing voltage. That would’ve been a better test. But I took all the photos for this maybe two months prior to doing this write up on it; and I don’t feel like going back to it for something this minor. However, I will for the next article that uses this drag racer. This test was bad.
BPS powered Motor (freespining)
BPS powered Motor (jammed)
Battery powered Motor (freespining) #1
Battery powered Motor (jammed) #1
Battery powered Motor (freespining) #2
Battery powered Motor (jammed) #2
Closing thoughts.
Why make this thingy? (technical term)
I wanted to make a very basic bare-bones motorised toy car. The reason for this is that I think its a really good project to get a complete beginners feet wet in electronics, and more broadly in getting to actually making things in general. The scope of the project is small and its largely practical. There is very little in the way of actual measurements and maths. In addition, the tooling needed and materials used are basic and readily available, as they are salvaged cheap electronics and household sundries.
I think something like this is ideal for children especially since once they’re done, they end up with a toy they made themselves. Every time they play with it, they might get that little endorphin kick saying ‘I made that’ and before you know it — they’ve been bitten by the bug.
Another reason why a project like this is good is because unlike how many get a start in the general electronics hobby today – i.e. by purchasing kits and completing them. Creating something useful or of-value from junk promotes and develops a better skill-set then just putting together pre-made puzzles. Sure kits can develop people’s technical skills in doing so (like soldering), a familiarity for the various components involved, and even some trouble shooting and diagnostic abilities in order to get the thing that they put together actually working.
Usually though, in my experience once the kit is complete; be it an electronic dice, an AM radio, or what have you. It is done. At which point it is put down and forgotten. This is unless the person gets interested in one of the higher concepts the kit introduced them to; like in the case of how putting together a DIY radio kit can become a gateway to repairing radios or the ham radio hobby as a whole.
This is of course a good thing. However in general, purchasing kits has in my opinion limited returns (such as mentioned above), and can get overly consumeristic in nature. Buy the kit, make the kit, buy the next kit, make the next kit; and so forth. So what do you do when you don’t have the funds for the next kit, or have a child that becomes bored and thinks that’ll all this hobby has to offer.
Well that’s where one has to become inventive. Create your own kit. And from what? Whatever is around. Putting together machines of your own creation from junk develops imagination and creativity in people. It teaches them to see more than what an item is, instead it promotes seeing the parts it is made up of, and what it could become.
That old microwave the neighbour left out. Is actually not just worthless e-waste. It is actually a magneto, various high power resistors you can use as a resistive load in your experiments, and even a high voltage transformer that’s likely to get you killed. Obviously I am joking about the microwave, I am not advocating for inexperienced or immature people start with mains power electronics. Learn, but learn safely. I.e. Low voltage direct current devices.
Working with salvage also gives people very localised and consequently practical (read valuable) experience. This is because they’ll be working and tinkering with the local devices available to them. The same ones in their everyday environments, and in doing so they will gain insights into their workings. Insights that may lead them to modifying and repairing some of the same items for future fun and profit.
Note: I read over this, and even I can tell it’s pretty bloody preachy. I am not saying kits are bad, they are just another avenue for this hobby. Sometimes it’s nice to play with something that isn’t already broken. However I do think that (certainly basic) kits are transitionary. You make kits then you move on to fucking about with whatever takes your personal interest. And like I stated, kits are often a gateway drug to your chosen field.
Make no mistake what you are reading is the toned down version. The first draft was hard for even me to read without rolling my eyes in my skull. No need to thank me for sparing you that, but you are most welcome.
In a bid to make more immediately useful content, I’d like to start recommending some of the various tools that I use. In this case it is an online service. Namely Mozilla’s Firefox Monitor; or more to the point, it is actually the website: haveibeenpwned.com (HIBP), which Firefox Monitor uses to enable it’s service.
What do they do?
In essence Firefox Monitor and HIBP are used to check whether or not an email address is associated with a recorded data-breach. Keyword: “recorded”. It does this by using a database of known breaches provided by haveibeenpwned.com.
The purpose of this service is to allow people to ascertain whether or not, an online account (and the user information there in) associated with the email address: has been compromised in a known data breach; and thus in need of immediate remedy. Things like: changing passwords, recovery phrases, and generally being aware that any potentially sensitive information associated with that account, such as: full name, mother’s maiden name, GPS location, education, birth date, telephone, city, school, or business information has now circulated within the hacker community.
Additionally, it helps to know which company is to blame for the spike in volume of spam and phishing emails, that will most certainly accompany said breach. I don’t know about yourself, but that’s something I’d certainly like to know.
Why is this service important?
It is my belief that every solution begins with awareness, the awareness of the problem. Only then can we move to better the situation. This tool gives you exactly that.
In my opinion, the main reason why I think this tool is important is because the companies involved in the data breaches themselves are loath to make their customers aware of them. Even though it is in their user’s best interests; it is not in the businesses best interests to advertise any breaches beyond the legally mandated/enforced minimum. Furthermore, who knows what that actually even is when dealing with global or multinational companies that operate over many legal jurisdictions. This is especially true when dealing with larger companies with entire legal teams at their disposal.
This service is important because (still just my opinion): companies in general tend to quietly patch any security vulnerabilities as they find them, and move on hoping no-one has noticed. This is especially true when there is no internally confirmed security breach.
Whenever a confirmed breach does happen, the first thing that the company responsible does is downplay the scope and severity of it. This may (and probably does) include: not even publicly reporting the breach until it is already made public elsewhere, often at a much later time. In many cases there is even resistance to acknowledge fault after the breach is made public. This is most likely a bid to exonerate themselves of any potential legal liabilities involved.
At the very least acknowledgement of fault could be seen as weakness. Weakness that will shake public confidence in the company and/or service. Therefore it is in their best interest to maintain the general illusion of control and/or competence. It’s corporate PR 101. It’s just a shame that the company and it’s users’ interests don’t align within this circumstance.
Why should people use these tools?
Both Mozilla Firefox Monitor and HIBP are free to use publicly available tools. Both tools come from reasonably trusted sources. Firefox Monitor is the product of an open-source community driven effort, giving it a certain level of transparency. And HIBP was developed by Troy Hunt, an authority on the topic of digital security. Even if you don’t know who Mr Hunt is (and I didn’t prior to this post), the fact that the Mozilla team decided to use his HIBP database for Firefox Monitor means that they are vouching for it.
More importantly, the tools themselves can assist an individual with regards to protecting their personal information online. They do this by allowing the individual that exact thing that I mentioned earlier: awareness. Awareness of whether or not that person’s email associated account information has been circulated, and which company is at fault for it.
For example: if you used the tool and because of it now know that, an account associated with your email with company X has been breached; and along with that breach your “security questions” were revealed. Then now you know to both remove, and not to use those particular security questions, with any future account … ever. As they are basically permanently compromised. Forewarned is forearmed.
taken from https://github.com/mozilla/blurts-server
Difference between Firefox Monitor and haveibeenpwned?
Firefox monitor is a very slimlined version of the HIBP tool that gives the lay user just what they need, without overwhelming or putting off said lay user. It is rather idiot proof; merely requiring user’s to input their emails and press enter. That’s it. Firefox monitor also has been bundled in with a few basic articles on good security protocol, that may be helpful to the average user. Common sense stuff a lot of it, but you know what they say about common sense.
Although Firefox is the simpler tool to use, it must be said that HIBP is a far more robust tool. And the one that I recommend. This is because in addition to searching email addresses, it allows searching via: passwords, and domain names. The website also allows users to browse a catalogue of breached websites without running a search. Extracts below.
Ever wondered how many accounts have been breached because they used the password “love”? Wonder no more. According to HIBP, its 356006 times.
I have also perused a nice little selection of companies from HIBP’s catalogue of known breaches that you may find interesting.
Personal experience with a data breach.
Just an aside if anyone is interested. From reading the above “Why is this service important?” section, you might have gotten the idea that I may be ever so slightly cynical about the companies involved in security breaches like these.
Frankly speaking, whenever data breaches do happen, I do not consider the corporations involved to be “victims” of cybercrime, as many others seem to do. It is a nauseating sentiment. One that condones bad behaviour. This is because it is my personal belief that the vase majority of the cases are due to one core thing: a dereliction of duty. Them failing in their duty to protect the data that they collected. Little more.
In addition to consuming the various news articles about data breaches over the years. Ones that had the general themes of corporate incompetence. Like for example: employees carrying around sensitive data on unencrypted thumb-drives, only to lose them on the train. I also have a few examples of companies that leaked my very own personal information. All of this has coloured my opinions thus.
The most memorable is the online virtual tabletop gaming website roll20.net. The thing that rubbed me the wrong way about them is that at no point during the process did they ever take any accountability for allowing it to happen. They did eventually outline what information was taken, but they never offered an apology for their lax in security. Instead they covered it up with boiler plate (legal friendly) corporate speak.
Example: “The investigation identified several possible vectors of attack that have since been remedied. Best practices at Roll20 for communications and credential cycling have been updated, with several code library updates completed and more in development.” Assuming that is indeed true, the same could literally be said by any company involved in a similar data breach – just change the names.
Although from what I understand by reading the article that they linked in their post, technically (purely technically) this appears as though it’s not their fault. But rather it was due to the underlying technology that they used. At least that is the implication presented. I’d argue that they still made the decision to use said tech, and thus vouched for it by doing so. Making them responsible, at least tangentially. At least enough for a simple sorry. The closest their customers got to an apology was a “Frankly, this sucks.” Writing it in an official company blog post that they passed for a conclusive public report; authored by Jeffrey Lamb, the Data Protection Officer.
I remember thinking at the time that whoever was writing this was good at the bland formalities of corporate speak, but otherwise is (and excuse my French): a fucking dickhead. You have to keep in mind reader, that they only knew of their own data breach because of a third party report. One that was published months after the fact. The report was published in February of 2019, and the breach happened (according to Mr Lamb) sometime late 2018. No apology warranted, not even for missing the hack, until a third party told you about it months after the fact. They then go on write their conclusive report in august of 2019. So nearly a year, between data breach and the final public debrief, where they outline exactly what data was exposed. I call that incompetence. “Data Protection Officer” more like resident salary sucker.
The ultimate lack of accountability is what really rubbed me up the wrong way here. And why would they be accountable, there is little in the way of consequence it seems for these messes. There are even examples of customers defending roll20 in the comments, referring to them as “victims” of cybercrime. They aren’t the victims here idiot, you are! I’ll include some choice examples of this for your entertainment. Its customers like that, that make businesses feels like they don’t have to be accountable either for their actions, or in this case general inaction with regards to proactively protecting customer data. Please read through the example comment thread.
You really can’t reason with people like that. They have too much emotional stock in a corporation to admit to themselves that they got screwed by it. There were even people actually praising roll20 for it’s meagre efforts. A sum total of 2 blog posts, some notice tweets/emails, and for patching a hole in their own boat. Thanks roll20, stellar job. Shame about all my cargo sinking to the seafloor for the bottom feeders to enjoy. I mean you only lost my full name, my IP address (so my physical location), my password, oh and some of my credit card data. Don’t worry about that roll20 (not like you would), that’s my problem. Fuck those types of customers. Wankers.
Moving on. Another example of a gormless entity losing my data is ffshrine.org. A final fantasy fan site that I registered with in 2010 I believe; and haven’t used that account since 2010. Ideally, they would have flagged the account as non-active and deleted it after a couple of years. But alas, instead they just kept whatever details I gave them for the five years until their 2015 data breach. Where they lost subscriber passwords and email addresses. No warning email post event, nothing. Radio silent. I had a similar experience with tumblr back in the day. Radio silent. No accountability. Are you sensing a theme here, dear reader?
Closing thoughts.
I have written far more here then I initially wanted to, so I will keep this summary short. Tools like haveibeenpwned and Firefox Monitor are things that you as an individual can use to help protect yourself in cyberspace. They can help you take proactive measures to safeguard your own data. They can also show you evidence that the large corporations really aren’t as professional or as infallible as they like to appear.
And that when, they make mistakes; mistakes such as losing your data. It is often you that has to bare the brunt of the repercussions, with little if any repercussions to them. Maybe they incur a temporary stock dip. But the fact of the matter is, they’ll recover from it. However whatever data you provided them for safe keeping, well that’s now permanently out there. Enjoy.
For example. To this day I still get phishing emails that say something like: “hey MY_FULL_NAME, YOUR_BANK has detected multiple login attempts using PASSWORD_FROM_FFSHRINE.ORG to login. We have frozen your account because we suspect fraudulent activity. Follow the obviously dodgy link provided and give us your security questions to fix this.” Although I can recognise a phishing scam when I see one, many technology illiterate users can not.
And make no mistake, the companies that were lax in their security. The one’s that have the attitude that breaches happen; are the exact ones to blame for the perpetuation of the black market information economy. An economy that preys on people; the real victims. The people who trusted these corporations with their data, thinking it in safe hands. Not the corporations themselves whose lack of diligence and general incompetence allowed for the data that they were trusted with to be exposed.
Jeez… that got a bit preachy towards the end. Didn’t it? Sorry about that. It’s just seeing companies fobbing off their responsibilities, and then seeing customers with Stockholm syndrome defending these same companies against criticism – really ruffles my feathers.
#0015: Device analysis of an unbranded LED dynamo torch
Preamble
It’s rather hard to provide a useful review of an unbranded product such as this. Since it has no brand, and no model to specify; we can only identify this particular device by it’s general appearance. Unfortunately this can be an issue when it comes to stating anything definitive about the product. This is due to the unregulated variations and derivatives on the market. In other words, just because two of these unbranded devices are outwardly identical, doesn’t necessarily mean that the components (or configuration there of) are also going to be the same. Heck, we don’t even know if any two different units were made by the same OEM (Original Equipment Manufacturer). Consequently, your mileage may (and probably will) vary if you pick up one of these dynamo torches. I can only show you what I have in front of me; and I have a sample size of two.
Device Demonstration
Device internals
Schematics
Torch A
made using https://www.digikey.com/schemeit/
Torch B
Key:
L1: 5 mmØ through-hole LED (white) L2: 5 mmØ through-hole LED (white) L3: 5 mmØ through-hole LED (white) R1: 5.1 ohm resistor S1: two-state toggle slide switch V1: dynamo (AC source) B1: [x3] AG10 / LR1130 button cell battery
Possible modification
rectifier and capacitor on the dynamo circuit
Key:
DB1: Diode Bridge C1: capacitor
I think that perhaps some kind of rectifier followed by a capacitor on the dynamo circuit will provide the parallel LEDs with a more constant voltage. Allowing it to stay on with a constant light intensity for a little longer, at the cost of a few initial revs without any light output as the capacitor charges. Is it worth the effort? Not especially. It might just help prevent the sudden light dropout. I’ll need to test it out myself before I say anything definitive here.
As for the rectifier, I would recommend a full-bridge rectifier using four diodes for maximum efficiency. That is if there’s space for it. This is because this configuration inverts the AC negative voltage into positive, before passing it onto the smoothing capacitor. Alternatively, a single inline diode will simply cut the AC in half by passing only the positive voltage. It’ll do the job, but at the loss of the negative voltage of the AC. Although, this is lost anyway at the LEDs, since they’re diodes. With this use-case, I think we need all the efficiency we can get, and a full bridge rectifier may even make the device function a little better. Like I said it needs proper testing, that’s why I stated this as a “possible modification”, rather than my usual “recommended modification”.
EDIT (2021-02-04): On further thought, any benefits of rectifying the dynamo AC will probably be negligible. I believe this is the case due to the low voltage provided from the dynamo (approximately 2V AC) coupled with the forward voltage drop that will occur within the diodes themselves.
The example diodes I have (namely 1N5818) have a really small forward voltage drop of 0.45 volts at 1 ampere. Even this miniscule drop will have a notable effect on any resultant DC.
web link: https://www.bitsbox.co.uk/data/diodes/1N5818.pdf
Still I still think the idea of rectifying a dynamo’s AC to DC would be worth while if for no other reason then to make a generally more useful form of power. Unfortunately, for a dynamo of this output, it’s just not worth it.
a 920 cm length of 0.1 mmØ gauge copper wire (wrapped into a coil of ~276 revolutions)
Please forgive any inaccuracies in naming convention for the gears, this is the first time I have actually paid any attention to the subject of gears in general, and it appears to be a deeper subject than initially expected with quite the learning curve involved. The “latching spur gear” and “internal spur gear” are the ones where I hazard a guess as to what they might be called, this is because at the time of writing I was unable to find a named example of what I was looking at. It can be difficult to find something when one doesn’t know the keywords to search.
Gear system in action
Pushing force on the handle moves the spur rack against spur gear B1. B1 then rotates clockwise. This in turn rotates the conjoined spur gear B2 clockwise. B2 interfaces with spur gear C1, and rotates spur gear C1 counter-clockwise. Which in turn rotates it’s conjoined latching spur gear (counter-clockwise).
The swivel teeth within the latching spur gear are designed to lock into the teeth of the internal spur gear D1. Although this happens only when they rotate counter-clockwise within D1. In doing so they rotate D1 and it’s toroidal magnet. This rotation causes a flux in the local magnetic field. This is picked up by the magnetic metal of the “dynamo core” and transported via this core to the copper coil winding. Where it induces an alternating current that powers the LED lights.
Once the handle is fully pressed in, with the spur rack (A1) at the end of it’s track. The operator’s pressing force is removed. At which point the spring in the handle pushes the handle back out; and forces the spur rack to move back to it’s start position. In doing so it rotates spur gear B1 counter-clockwise this time, this rotation is passed on to spur gear B2. Which rotates spur gear C1 clockwise. This rotation is passed to the 2 tooth latching spur gear C2. Which in turn spins clockwise freely and allows the gear system to reset position. Then the process repeats as the operator pushes on the handle. And so on.
The device as a consumer product
Build quality
This is probably the cheapest dynamo torch on the market. If not in price, then certainly in build quality. The main body of the torch is made up of two separate mouldings that sandwich together. This configuration clips into the grey plastic ovoid that houses the LEDs, batteries, and the light guide/reflector. Add to this one or two (depending on version) small self tapping phillips screws to keep the device together.
The phillips screws for the housing are set into thin moulded standoffs that seem prone to either splitting at the screw thread or cracking at their base. The cracks on the base of these standoffs I believe are caused by the general mechanical stress incurred by the gear and spring system. Both in action: when the dynamo mechanism is being used, with the spring loaded handle being vigorously pumped back and forth; and at rest, because the spring that pushes the handle back out puts a constant stress on the gears that are set into these flimsy standoffs.
I have had these two torches in safe storage for a few years, I was surprised to find out that one of the two had broken it’s standoffs, well off. Considering my storage solution (think sealed plastic tub in a garage), this may have been caused if not exacerbated by temperature variations, in addition to the stress of having a coiled spring pushing against them. But basically, I put the thing away fixed, and found it broken. Considering that one of the use-cases the online retailers advertise this thing for is camping, I don’t think that the temperature swings of the mild british weather should have caused this.
Something positive. The internal components I generally have little problem with; from the LEDs, to the Dynamo, and nylon gears. They are all very inexpensive components, but there is nothing especially wrong with them. They are all basically fit for purpose. Even the dynamo, although unfortunately, it’s delicate hair thin wires extend out the dynamo coil and into the device proper: towards the switch and LEDs. This makes the device far more likely to suffer a breakdown, as these wires are far too thin and delicate to be used for general device circuitry. Especially when in the presence of an unshielded gear-system. Look at the pictures to compare the dynamo wire (~0.1 mmØ) to the LED (~0.4 mmØ) or switch (~0.5 mmØ) terminals to understand just how thin the dynamo coil wire is. Please note: inaccuracies in recorded measurements are due to the pictured calipers used … and me.
False advertisement claims
I have seen this torch (and it derivatives) in multiple online stores. I have also seen a lot of false advertising around this product across multiple vendors. Including Ebay, AliExpress and especially Amazon. This is predominantly due to the seller’s lifting the product descriptions from each other, in some cases they’re literal copy-pastes.
There are many claims on these store pages that made me chortle. These included: “High tech ultra bright LEDS” when referring to the 3 bottom market 5mmØ through-hole LEDs; or the sentence “perfect for outdoor use” when describing an electronic product that is about as watertight as the average kitchen sponge.
Since these claims made are subjective, you can’t say that they are technically wrong, because that’s just like your opinion man. These are (in my opinion man): just examples of product puffing or marketing wankery. Something that I honestly have come to expect at this point in my life. Whenever I go to buy something, I will inevitably have some to sit through at least some marketing bullshit, because apparently every single product ever made, is as great a sliced bread, and should get you as excited as the second coming of our lord and saviour. Or else there is clearly something wrong with you.
Moving on. Something else that I have come to expect, and let’s be honest here – enjoy: is Chinglish. And there are some great examples of this within these product descriptions. My favourite is “Works on a new technology of pressing handle with your hand.” Hey, it made me smile. Here’s another doozy for you: “LED torch adopt advanced technology of LEDs emitting level of 3 fluorescence tube”. What the actual fuck are they trying to say?! If internet scholars ever decrypt this product claim, you can probably safely bet that is it some form of bullshit.
Which nicely brings me to the real issue that I have with these product ads. It is the genuine examples of outright falsehoods. The main two claims that I have issue with, are: 1) That the dynamo action charges the batteries, and 2) That the product doesn’t include batteries in the first place.
For the first example I have an ebay advert that uses the keyword “charge” in it’s description and makes mention of the 3 disposable AG10 coin batteries that come in the unit. Although it doesn’t mention that they are single charge disposable units. Hence the assumption that the average consumer is likely to make is that the dynamo charges these batteries. Another amazon ads states the claims “No batteries required, Eco and rechargeable”, to make the customer think that it comes with some kind of componentry that either enables the device to charge without batteries (e.g. capacitors), or that the device comes with built-in rechargeable batteries.
Unfortunately neither are true. A cursory look at the above schematic for either unit A or B will show you that at no point does the dynamo charge the batteries. They are on two separate loops. Also, where is all the charging circuitry? The bridge rectifier, voltage regulator, and smoothing capacitors involved in converting the alternating current that the dynamo would produce into a fixed voltage direct current for the batteries. Additionally, even ignoring those facts: let’s say after reading this paragraph someone still isn’t convinced of my claim that the dynamo does in fact not charge the batteries; then why does this torch ship with disposable (non-rechargeable) alkaline AG10 coin batteries then? It’s because this claim is provably false.
Now onto the next false claim. This was the one that I took notice of initially, and actually inspired this rant. The claim of these torches not having a battery to begin with. The disproving evidence of this claim in some cases is in the bloody product description itself. I have even seen adverts that claim that it doesn’t have batteries, to then make the contradictory claim of a 15 minute running time at full charge.
Closing thoughts
I honestly never intended to talk this much about this budget torch. However the more I looked into the item the more I found to say. To sum it up for you: everything from the build quality, to the false claims: make this thing is absolute dreck.
I think the main reason as to why these types of products can make outlandish claims and still sell is because of their price. They are so inexpensive, that returning them may cost more in unreimbursed postage costs, than the refunded price of the product. For example: a torch costing approximately £2.50, will cost £3.10 (at time of writing) to return via a Royal Mail UK only “small parcel”. This is of course assuming that the customer bought the product from a UK distributor.
If it was bought from China, then a return is basically not financially viable. The international postage is only cheap one way; and that’s due to bulk export shipping from China. Consequently, I have had experiences with seller’s who have contacted me offering a full refund with no return if I removed a (well deserved) negative review I have given for the product. That’s likely the main reason why they have such high reviews (4/5 star average on amazon); because they buy off the negative ones; like mine.
As for my final word on the torches themselves: I think that they are basically designed to be factory fresh e-waste. They will go from the factory, to the seller, to the customer, and to the bin faster than should be acceptable. This due to their own shoddy nature and little else. They are a good testament to the saying: “you get what you pay for”. One could also use the saying “buy cheap, buy twice”, that is if a person actually intended to use these torches for their advertised use-cases. Good luck camping with this piece of hot shit in your back pocket.
#0014: Tip for reinserting self-tapping screws into plastic housings
What is a “self-tapping” screw?
Whenever one removes screws from a device – especially a mass produced consumer grade device with a plastic housing; then chances are that the screws that were removed were “self-tapping” screws. As the name suggests, these are screws that are designed to cut their thread into the inner diameter of the plastic hole of the device housing that they are inserted into at the factory.
All self tapping screws have a few distinct qualities in common. These include: a relatively deep thread in order to cut into and grip the plastic, and a wide pitch between these threads in order to more effectively slide into the material. Additionally most self tapping screws tend to come to a sharpened point in order to to aid in aligning the screw as it is inserted into the hole.
So what’s the actual tip?
Well, when reinserting a self-tapping screw into it’s plastic receptacle. It is good practice to initially rotate the screw counter-clockwise (loosen) until you feel it pop or click into place. This process aligns the screw with the pre-existing thread, and in doing so means that when the screw is screwed in, it will slide into the already established thread and not cut a new thread over or across the old one. When aligned correctly, the screw should screw into the hole with very little resistance.
Why use this method?
The reason why this is important, is because repeated re-boring of the plastic hole will eventually strip it out of any threading. This is because each time a new thread is cut into the plastics it removes material; which in turn incrementally widens the diameter of the hole in the process. This can continue to the point that it can no longer effectively hold the original screw within it. Avoiding re-tapping the thread every time you reinsert the screw will minimise your damage footprint when repairing/working on the same devices repeatedly. Which is always good.
Video demonstration
Please note: although it may look like I am using force to reinsert the screw, I am not. It’s just the awkward angle and set up that may make it appear that way.
What to do with an already stripped or overlarge hole?
There are a few remedies to take if this advice is coming to late. The quick and dirty solution is to use a larger size self tapping screw that then can cut a new thread into the widened hole. After which one has to then absolutely makes sure to always realign the new larger screw with it’s thread before reinserting it. This is because any further damage to the plastic hole may make it entirely unusable. E.g. a plastic stand-off splitting entirely due to it’s enlarged hole.
The more intensive repair requires filling the hole with something that the original sized screw can then bite into. The most likely materials used here are either hot glue for a “temporary” fix; or melted plastic of the same type as used by the device for a more permanent solution. If you use the melted plastic route: I recommend filling the hole entirely, then drilling a new hole of the correct diameter. Followed by finally using the original self tapping screw to cut a new thread into this virgin material.
#0013: Repair of a game controller with fatigued dome switches
What is a dome switch?
In order to know what dome switch fatigue is, we must first identify dome switches. Dome switches are buttons that utilise a dome made from silicon, rubber, polyurethane; or a similar material with the same elastic properties. This dome effectively acts like a spring and pushes the button back up when applied downward pressure is removed.
A typical dome switch will consist of several parts. These are: a (usually) plastic keypad key, an elastic dome, and a graphite pad. The switch key (or button) is mounted onto the elastic dome, additionally the graphite pad is attached to the concave or underside of this dome; and finally, this assembly is sat atop a patch of unconnected unmasked circuit board traces. These traces essentially function as switch terminals.
The idea is that when the downward force is applied to the key, the elastic dome is compressed; causing the graphite pad to press down on the unmasked PCB traces underneath it. This graphite pad actively bridges an electrical connection across these traces, due to graphite’s electrical conductivity.
When the connection is made across these traces, a logic level electric current (around 3.3 volts) is either pulled down to or pulled up from signal ground. It really depends on the IC (Integrated Circuit) chip that is managing and interpreting the keypad array as to the specifics. Anyway, the point is, essentially that is how the computer knows which buttons are pressed and for how long. After the pressing force is removed, the elasticity of the currently compressed dome material causes it to reset to it’s original domed profile. And in doing so it lifts the graphite pad from the traces and breaks the electrical connection.
Example of dome switches within a handset phone
Diagram of dome switch in action
image taken from: https://i.imgur.com/5K9Uy.gif
What is dome switch fatigue?
Dome switch fatigue, or more specifically dome fatigue: is when the domes within dome switches, develop a fault due to extended use that makes them no longer effectively reset their position. I.e. pop back up after they have been compressed.
The main symptom of dome fatigue is button sticking. In other words, when a button is pressed down, it either takes longer than it should to reset, or it stays down all together. This is assuming that the keypad is actually clean, as there are many reasons as to why a button might stick other than dome fatigue. Accumulated grease or oils, foreign objects (like food), and dust build up can easily cause button sticking.
Once the device has been opened, the domes themselves can be examined. Look for stress lines: thinner (often lighter) areas of material that can indicate structural weakness. I recommend comparing the suspect dome to it’s known good neighbours; adjacent domes from the same device that occupy buttons that don’t stick. Since they are from the same material stock and often from the same actual moulding as well (as is the case here), it can make spotting any actual stress signs easier. Common sense right?
As you can see in the example picture, there is a stress ring on the one of the four action button’s domes. This dome corresponds to the “A” button on an imitation USB Xbox 360 controller. Now I don’t mean to go on a tangent but I will say that imitation products like this controller are generally made to a price-point. I.e. the manufacturer cuts certain corners to bring the unit price down.
This is done in a bid to undercut the original product and sell itself as a budget alternative. In many cases the cut corners and lower quality product is mostly acceptable to the end user, as it is reflected in it’s price. However, these cuts tend to including: the sourcing of lower quality, less durable materials.
I believe this to be the issue here, although I haven’t had this controller for long. (Approximately a year.) I use this controller to mostly play platformers such as Splelunky. Since the “A” button is used to jump, it is by far the most used button; and it seems like over the time that I have owned it, I have just fatigued this particular dome. Either by some kind of repetitive flex damage (i.e. general use fatigue), or by just pressing too hard on it in moments of panic or frustration during play.
Example of “sticky button”
Example of fatigued dome
Repairing controllers with fatigued buttons
Sadly, an actual and effective repair of the dome itself is outside my capabilities. I just replaced the knackered dome with a fresh one. Well… a less knackered dome from a spares unit. As you can see I chose a third party “4 gamers” brand PlayStation2 controller as a donor unit. This is because that is all that I had on hand at the time. Additionally I am generally unwilling to purchase materials for a repair unless I have to. And to be honest, when it comes to repairing budget electronics such as this controller, it really is hard to justify spending any amount of money for materials, when one could spend a little more and purchase a new unit.
With this repair, I initially intended to replace the entire action button array (all four buttons), with domes from the spares unit. This is because the different types of domes will have different force pressure resistances, and bounce back elasticity. Which would lead to users experiencing different levels of tactile feedback or “button feel”.
At this level, I don’t mind much what the exact tactile feedback of the spares domes are; as I doubt specifying tactile feedback was much of a concern for this budget controller to begin with. Ergo this slapdash replacement wouldn’t necessarily denote a loss in overall device quality or user experience.
However I would mind if the feedback of the grouping of action buttons wasn’t uniform (or near enough). I.e. if one button was noticeably stiffer or mushier. That disparity in tactile feedback may actually become a distraction during play. It may even negatively affect a player’s performance; due to the player becoming accustomed to the tactile feedback of one button and then because of that either pressing to hard or not hard enough when they move onto another button (with a different level of resistance) in order to perform a different action. It may cause a misclick; either registering two inputs, if the new dome is significantly weaker/squishier or none at all if the new dome is significantly stiffer than the previous.
Unfortunately, I ended up just replacing the tired dome and using the rest of the three originals. Even though I have a picture of all four action button domes replaced on the controller. I dropped one on the floor shortly after that; and after 30 mins of searching. I just adapted to this strategy. In this case the new dome and the originals have similar (although not the same) level of tactile feedback to them. They aren’t different enough to be an issue. Not for me at least.
Spares unit
Application of spare dome(s)
Demonstration of device repair (before and after)
Original fatigued dome switch (green “A” button)
Although tactile feel can not be conveyed: notice the mushier, softer sound from the green “A” button when compared to the others.
Replaced dome switch (green “A” button)
The sound produced from the replaced dome is similar to the other three buttons, although they are not uniform themselves. There is an acceptable level of difference within tactile feedback across the buttons. The sound of the buttons when pressed reflects this.
Final thoughts
To sum up my basic ethos when it comes to repairing a device with fatigued domes. One, one has to replace the domes. As far as I can tell the domes themselves are irreparable. Two, When replacing the domes, it may be better to replace known good domes in a bid to get a uniformity of tactile feedback on all the buttons on a device, or at the very lest on a significant button grouping. Such as action buttons or directional (D-Pad) buttons. That’s the takeaway.
That’s all folks. Thanks for reading.
References, links, further reading
“Diagram of dome switch in action” gif taken from: https://i.imgur.com/5K9Uy.gif https://www.mechanical-keyboard.org/advantages-and-disadvantages-of-mechanical-keyboards/ https://en.wikipedia.org/wiki/Keyboard_technology#Dome-switch_keyboard
#0012: A personal perspective on the end of the Adobe Flash era
What is Flash?
Adobe Flash is a multimedia software platform. However the term “Flash” is used as a catch all term for any software that utilizes this platform to output media. The Flash technology allowed webpages to host media on them in the form of embedded files; encoded into either the Flash Video (.FLV) or Shockwave Flash (.SWF) format. In order to run these media files, one required the use of a web browser plugin called the “Adobe Flash Player”.
Flash first became prevalent in the late 90’s, early 2000’s as an evolution on the static webpages of the time. Where it was basically used for every animated media webpage element (barring animated .gif images). Including (but not limited to) delivering: video, music, and animated advertisements (e.g. banner ads with audio). It also allowed for interactive media, namely internet browser games. It did this by allowing the browser media access to user’s system inputs (e.g. keyboard and mouse).
In essence if you browsed the internet during this time and interacted with web media. Be it watching a video, playing a game, listening to music, or watching text scroll on a fancy ad. Chances are good that it was delivered to you using the Adobe Flash web player. It can not be understated, that Flash was ubiquitous in it’s time.
The decline of Adobe Flash
Ever since Adobe’s 2017 announcement of the official retirement of their Flash technology platform, for the close of the year 2020; the internet has been abuzz with people both decrying and celebrating the end of the Flash era. Even within the years leading up to Adobe’s 2017 announcement, I have seen Flash’s relevance steadily drop off as the emergence of alternatives such as HTML5, ate up Flash’s market-share.
There are number of reasons as to why people migrated from using Adobe’s Flash player to HTML5 for delivering webpage media. Predominantly, this is because of the public’s perception of the Flash web player having numerous security issues. Whether this is true or not, or simply exaggerated; I can not much comment. What I do know as a former Flash game dev is that you can make whatever network calls you want, as well as access the user’s local system; in order to get at anything from keystrokes to cookies. Then wrap up that code into a fairly innocuous looking .swf file, and embed it into a webpage. Hmmm… I guess it did have security issues. But having said that I am not going to pretend to be in the know, when it come to network security of the 2010’s and Flash. I only used it to make browser games. The network calls to allow online game saves, the cookies for local game saves, and keystrokes for user input.
Flash’s security issues in my opinion were compounded by it’s proprietary and closed source nature. There wasn’t an easy way to check what that embedded .swf file was going to do until it did it. Consequently it made malicious code very difficult to find. HTML5 on the other hand doesn’t suffer from this issue, since it is largely open source. Although most developers these days use APIs (Application Programming Interfaces) or frameworks, such as AngularJS or JQuery to make sites, or Phaser to make games. I.e. they don’t code them from scratch; the code for these tools however is there and public facing if you are inclined to look.
The openness of using HTML5 (Javascript, CSS) based technology means that it is inherently safer than Flash. Since the browser acts as an interpreter for the source code, rather than just a medium for embedded compiled binaries (.swf files) where code can hide. I don’t generally like speaking in absolutes, because there are undoubtedly exceptions to this. However in a general sense this is the case when it comes to Flash and HTML5.
Additionally Flash had another issue and that was it’s lack of support for mobile devices; as it was designed for the prevalent desktop platform at the time (~2008). This was in my opinion the death knell for Flash, as the explosion in popularity that internet capable mobile devices had between then and now (2020); just meant that Flash’s market-share essentially shrank proportionally to this.
Steve Jobs (CEO) of Apple published in 2010 an open letter called “thoughts on Flash”, where he cites a number of reasons as to why his company does not use the Flash technology in their products. Namely their iPhones and iPads of the time. His reasons included: Flash’s security issues, it’s closed source nature, it’s lack of optimisation for touch interfaces, it’s negative affect on battery life, and more. Link below for the full article.
Considering what the Apple CEO thought of Flash, it was no surprise that Apple was the first company that outright disallowed Flash from their platform (iOS). This meant that at the time, Flash was only supported on Android devices; and even that dropped off in the later years since the issues that Jobs cited weren’t addressed to a satisfactory degree. In hindsight, it appears as Apple’s dismissal of Flash was a canary in a coal mine. A prelude to it’s collapse in general.
I should mention that I am not really here to talk about Flash’s history. I am not a Flash scholar, nor am I interested enough in it to become one. So take what I have said with a pinch of salt. If that is what you are looking for, there are better sources for that content. I suggest starting with Adobe’s official blog, then the wikipedia.org articles, then follow their sources and read those — as well as random blog posts by internet weirdos like this one — they are always fun. What I am here to do is to talk about Flash as it relates to my experience as a game developer. The games that got me interested in it, and the games that got me out.
About me
A bit of background about me. I attended school up until the mid 2010’s, and grew up (when compared to my working class peers) relatively poor. I.e. no home internet and I had to play outside alot. Gasp! I’ll keep it vague because this is isn’t really about me, however the information is relevant. My first experience with the internet in general was in the mid 2000’s. Where it was largely a utilitarian space as far as I was concerned. This is because I never had the time to explore it at my leisure. My access was always in a public place. Ergo monitored, censored, and timed. Either at school in ICT (Information Computer Technology) class using the “Yahooligans” search engine (remember that?), or at the local library with that creepy moustachioed librarian woman breathing down my neck. Occasionally I could even be found at an internet cafe paying £1 for an hour of uncensored access whilst some indian dude watched what I did from his master console. Hi Mr Singh!
Consequently, my use of the internet was always objective or mission based. I went in not to explore and learn, but with an objective. Especially when I was paying for the privilege (and it is a privilege). I remember being at the internet cafe and booting up my collection of anime sites that allowed downloads (RIP cyber12.net) to get the latest 360p Horrible Subs copy of the Bleach or Naruto episodes, that just aired the previous week in Japan. I recall cramming as many of those ~50MB episodes (.RMVB video format), as well as Final Fantasy wallpapers, low quality D12 or Linkin park MP3s, and “kawaii ecchi” jpegs into a 256MB thumb-drive that I got second-hand from me mum. I would then take this bullshit home to my HP Pavilion A320N in order to fill it’s massive 50GB 3.5′ IDE hard drive, for my repeated media enjoyment. Life was simple back then.
So, what was I doing while the media files downloaded at a blazing 120KiB per second download speed? Well, I was playing Flash games of course! Keep up. I remember each episode download taking roughly half an hour, although I don’t know if the speed and file size numbers that I gave match up… probably not. The fact that I still (mostly) remember these numbers a decade later should tell you how much of an impression the experience left on my young supple mind.
Anyway, While the files downloaded, I’d hit up game sites. Websites, like: Newgrounds, Miniclip, Armourgames, and of course Kongregate. The usual suspects. What games did I play? Games like “Rebuild”, “Epic Battle Fantasy”, “Bubble Tank”, “Sonny”, “Armed with Wings”, or puzzle games like the “Escape the room” series; as well as the clones upon clones of GBA (GameBoy Advanced) tactical games like: “Final Fantasy tactics” and “Advance Wars”. Additionally I played excellent point-and-click titles such as the “Reincarnation” series, or Clickshake’s “Ballad of Reemus” series, or Zeebarf’s “A small Favour” series. These same quirky point-and-click puzzle-adventure games inspired me to create my own.
Why? Well because up until then I had only played MS-DOS point-and-click games. Like Sierra’s various “-Quest” series games. Think: “Police Quest”, “Space Quest”, “King’s Quest”, etcetera-quest. Additionally I played “Simon the Sorcerer” 1 and 2, “Sam & Max: Hit the Road”, and of course “Leisure suit Larry”. As an aside, I never played the famous Lucas Arts games like “Monkey Island” and “Day of the tentacle” until I was an adult. I am a victim ;_;.
Although the MS-DOS games sparked the love of the point-and-click adventure genre, their Flash counterparts brought the realisation home that I actually could do it too. They were fun, they had the heart of the older DOS games, but the technology was much more accessible, and they were significantly shorter. As far as I knew MS-DOS games were made using ritual possession via offerings to the Omnissiah. It was hard enough to install them and get them working properly, let alone make the bloody things. The learning curve involved was just far too sheer for my young self to effectively engage.
Whereas Flash used ActionScript3, and an IDE: named Adobe CS3. Heh, even rhymed. Sort of. ActionScript3 was as friendly as abstract programming languages come, and there were a plethora of online tutorials, both in the form of textual articles as well as youtube and dailymotion videos. This abundance of guides and media motivated me to “‘ave-arr-go!” as they say.
Developing Flash games
Developer resources for Flash media were abundant at the time. My favourite of which, is the open-source IDE (Integrated Development Environment) Flashdevelop! This was my IDE of choice because: 1) I couldn’t afford an official copy of Adobe Flash Professional (or Adobe Animate as they call it now), and 2) I didn’t trust the “unofficial” versions that I found. So FlashDevelop became my de facto IDE of choice and the open-source Flex SDK (Software Development Kit) as my .swf complier of choice. I should mention that this was also my first practical interaction with community driven open software, and it really opened my eyes to the liberation that it offered.
That is, not being tied to any particular company for one’s productivity tools. No cloud subscriptions, no periodic reminders to renew the lease, no “””anonymous””” telemetry phoning home… It’s actually a rather dangerous thing to get accustomed to, because it spoils a person when you realise how shit a lot of proprietary applications become with this bloat. I mean I understand why a lot of it is there, it’s just a shame that it punishes (inconveniences) the paying customer and not the pirate. Who’s most likely running a cracked version (in a virtual machine) without the bloatware. It’s all academic though, because I couldn’t afford it anyway. So it didn’t really matter what I thought about it at the time (or even now really).
The main disadvantage I recall Flashdevelop having when compared to Adobe Flash CS(-whatever), is that Adobe Flash had an animation timeline that it centrally used. This timeline was designed to have various Class objects attached to it at various points or frames. In AS3 an object class is used to encapsulate an entire source file in general. With regards to games: the online tutorials would attach a LoadingScreen.as3 Class to frame 0, then the MainMenu.as3 Class to frame 1, and so on. It does this without necessitating verbose instructions to the program as to how to handle them, as this was done automatically using the timeline. The idea is that when one frame terminated, an automatic call would be made to move to the next frame, and then run the attached classes and the methods contained within.
FlashDevelop on the other hand had far less visually accessible components (like the various art tools or timeline) when compared to the Adobe Flash IDE; and consequently it was less user friendly. At least initially. However once the learning curve was surmounted, it proved to be a very robust IDE. One thing that didn’t help young me, is the fact that the vast majority of the online tutorials were create specifically using the Adobe IDE; and unwittingly used features only present within that IDE — such as the aforementioned timeline.
For example: it took me quite a while to learn the correct techniques to create a functioning loading screen in FlashDevelop because of this. There was a lot of chopping up of other people’s code, then trail and error to get it working. And once it worked, to then to try to understand why in order to reliably replicate the method in future projects.
I remember managing source files in the FlashDevelop IDE being similar to the C++ IDEs I used at the time. (CodeBlocks, Eclipse, Bloodshed Dev-C++.) For example, having to first manually import other code files in order to make calls to their functions or add their objects to the stage. This is in contrast to the Adobe IDE which glossed over much of this type of stuff by using the timeline and a drag-and-drop interface. Where Users would drag an image onto the stage and then click on it to open a box where they’d add in any additional code. The Adobe IDE seemed like an interface designed for animators first and for most. That’s because it was. Whereas FlashDevelop was more of a programmers IDE. Where a lot of the animation tools of the Flash IDE were absent.
I realise that this is more a criticism of me rather than FlashDevelop, however Speaking of FlashDevelop and inconveniences. I do not miss the tedium of manually embedding large volumes of images with this IDE. Then casting them as “bitmaps”, to then place them into individual “movieclip” containers. All with mandatory unique names, by the way. This, in order to allow manipulation of the asset when it was finally added to the stage. At which point I had to manually assign their dimensions (width, height), alpha (transparency), and initial stage (x,y) location. To then use an external tweening library (forgot it’s name) for actually animating these images. Think sliding alpha gradients for flickering lasers, and gradual increase/decrease of an X position variable to make sliding doors open/close. Doing this for every image in a game got laborious quickly, and if I had to do it again I actually would have created helper functions to do it for me. Young me laboriously hard coded it all, and consequently learned good lessons.
Lessons on the difference between working hard and working smart. In this case, on making the time to create utilitarian recyclable functions. Ones that can take the various image’s stats as arguments and return what I wish. The strength of them is their recycle-ability, which leads to cleaner code and the avoidance of long lines of repeated hard-code. It would be instead just one line for each new image: citing the function call and the specific image’s stats as arguments for that function. But I guess a lesson learned the hard way is a lesson learned forever.
Developer migration
It seems like around 2011-2013 was the time when the Flash exodus really begun. Known creators begun to either drop off or change to other things. Around here in my opinion is also when the golden age of Newgrounds effectively ended. You can see from the example of popular Flash animators of the time (Zone and Tiarawhy), how their content either dropped off and/or changed significantly in a bid to reinvent themselves.
example of a creator’s flash media submission fall off
I remember when it came time to move on from the Adobe Flash player and browser games in general. I tried out Adobe Air because like many developers who started out with Flash games, I wished to pivot to creating games for other platforms. For me it was the desktop. I wanted to make “proper” point-and-click games, and hopefully earn a buck or two doing it.
Even back then the public perception of Flash games, was as a means of getting a developer’s feet wet in making games and little more. Sooner or later if the person is serious about making games — and serious about making a living, making games; then they have to move on to another platform. Many migrated to making mobile games for iOS and Android. Even in cases where the developer’s still wanted to make browser games, there were better (more lucrative and future-proof) technologies/paths to that.
I have seen many developers move on to using the emergent Unity technology during this transitory period. Unity allowed the creation of multiplatform programs whilst still using the same core codebase; just exporting it into different media formats appropriate to their target platforms. This includes desktops (Windows, Macintosh, and Linux), mobile platforms (Android, iOS), and in this case even web browsers by using the Unity Web Player. At the time I opted to stick with my current tooling, because the idea of being “set-back” by having to learn another system (Unity and C#) would stifle my ability to actually finish games. Its only with time that I have understood that a person never stops being the student. In order to progress optimally in any discipline one should not shy away from learning new things when the opportunity makes itself apparent. If I did keep up with making games, I would have had to retool anyway. Better to eat crow while it’s still young and tender.
I believe my first introductions to the Adobe Air technology was via two games in particular. Edmund McMillen’s original “The Binding of Isaac” and Jasper Byrne’s “Lone Survivor”. Although other devs followed a similar path like Amanita Design and their game “Machinarium”. But the prior two are the one’s I had hands on experience with. Anyway, once I purchased a copy their games, I found the core .swf files in their source folder and a native executable that called them. Along with a bunch of Adobe Air library files. I remember that the .swf files could also be played using a local version of Flash player; bypassing the native executable in the process. Meaning that Adobe Air itself, as I understand it just wraps the .swf file with an .exe.
So in an attempt to ape them, I downloaded the Air SDK and used it. It wasn’t hard to import Air into FlashDevelop and create a desktop app using it. I recall there being minimal code alterations in the process. I should state that I did so initially as an experiment, but I will do so again and host the .zip archives on this site once/if I can find my source files again. For posterity, and as a means of providing anyone interested with a playable copy of my early games.
Closing statements
That’s all I really have to say when it comes to Flash. I loved the games I played as a child. They introduced me to many new genres of games. From Zombie shooters, to puzzle games. Consequently I have a lot of good memories with it. I never really cared or noticed when websites stopped using Flash for banner adverts or for delivering videos (like youtube.com), as it really didn’t matter to me. I did however notice, when Unity web player, Java web player, and HTML5 games slowly started to become more and more prevalent; or when Flash animation died. And for good reason.
Flash is very limited. I remember the frustrating media file size embed limits. Well, you might say that I should’ve just used a loader class to load in external media as needed, but that had it’s own associated issues. Such as the program not finding the files (once online) that you uploaded with it. And some sites at the time would only allow one file upload (the .swf file) with no supporting media files. Where others had a size limit for the actual .swf file itself. I remember having to strip out a lot of embedded music (.mp3) out of my game “Last Life: The Blue Key” because kongregate had a .swf file size limit.
For many reasons like this, Flash got over taken by it’s competitors in it’s space. Then for other reasons (think Steam games sales, Apple iOS games, and plummeting ad revenue), the market for browser games in general fell off. Making it a space largely for new developers to cut their teeth and little else. Now, I don’t think it’s even that.
That makes me wonder; what will happen to all these browser game sites like Newgrounds and Kongregate. Although they host games using various technologies; their decade plus backlog of games is going to be in the Flash format. Their games catalogue is going to get gutted. And I don’t think that many (if any) developers are actually going to back to a game they made (probably as a kid) 10 years ago and remake it for an unprofitable platform. I know I am not. I have moved on from games in general, and even if I got back into it (which I want to), I’d work on a new property. I’d honestly be surprised if these sites still exist in a couple of years because of this.
Still it’s not all doom and gloom. Although Kongregate seems content to let their Flash content die on the vine, Newgrounds created a custom Flash player just for this reason. Although it seems like a bit of a patchwork or stopgap measure. It is much better than nothing.
Anyway, the good Flash games, the one’s people loved from this era. They’ll be preserved. The online copies can be stripped from the web browser (while they are there). Saved, and played locally using a desktop version of Flash player. And for the one’s people didn’t care to preserve. Well, like so much else in life: they get lost to the sands of time.
Thank you for reading.
One more thing…
This made me laff, but mostly because Flash is Ded. RIP.
References, links, further reading
https://web.archive.org/web/20171202123704/https://theblog.adobe.com/adobe-flash-update/ https://www.cnet.com/products/hp-pavilion-a320n-athlon-xp-2800-plus-2-08-ghz-monitor-none-series/ https://www.flashdevelop.org/ https://blog.adobe.com/en/2019/05/30/the-future-of-adobe-air.html#gs.na44sx https://helpx.adobe.com/security/products/flash-player.html https://en.wikipedia.org/wiki/Adobe_Flash https://en.wikipedia.org/wiki/Adobe_AIR https://en.wikipedia.org/wiki/FlashDevelop https://en.wikipedia.org/wiki/Apache_Flex https://en.wikipedia.org/wiki/MS-DOS https://en.wikipedia.org/wiki/Open-source_software https://en.wikipedia.org/wiki/RMVB https://en.wikipedia.org/wiki/Edmund_McMillen https://en.wikipedia.org/wiki/Comparison_of_HTML5_and_Flash https://en.wikipedia.org/wiki/HTML5 intro to tweeining: https://www.peachpit.com/articles/article.aspx?p=20965 example of Adobe IDE specific tutorials: https://helpx.adobe.com/animate/using/shape-tweening.html “Thoughts on Flash” by Steve Jobs Primary Source: https://www.apple.com/hotnews/thoughts-on-flash/ Secondary Source: https://appleinsider.com/articles/10/04/29/apples_steve_jobs_publishes_public_thoughts_on_flash_letter Secondary Source: https://medium.com/riow/thoughts-on-flash-1d1c8588fe07 https://en.wikipedia.org/wiki/Thoughts_on_Flash https://en.wikipedia.org/wiki/HTML5#%22Thoughts_on_Flash%22
#0011: Copy-paste of “Thoughts on Flash” by Steve Jobs (2010)
Preamble
This is a transcription of an open letter written in 2010 on the subject of Adobe Flash by the CEO of Apple of the time: Steve Jobs. I paste it here for referential and posterity purposes.
Rather annoyingly Apple has since removed the original article from their official company website, so this is a copy from a secondary source. An archive website called: web.archive.org (A.K.A wayback machine). This was then verified by comparing it with copies from other website articles published around 2010. Check the links and references section for specifics. I think this is a good illustration of the fragility of information on the internet. When primary (controlled) sources can suddenly disappear; we have to rely on secondary sources and their general trustworthiness.
(START QUOTE)
Thoughts on Flash
Apple has a long relationship with Adobe. In fact, we met Adobe’s founders when they were in their proverbial garage. Apple was their first big customer, adopting their Postscript language for our new Laserwriter printer. Apple invested in Adobe and owned around 20% of the company for many years. The two companies worked closely together to pioneer desktop publishing and there were many good times. Since that golden era, the companies have grown apart. Apple went through its near death experience, and Adobe was drawn to the corporate market with their Acrobat products. Today the two companies still work together to serve their joint creative customers – Mac users buy around half of Adobe’s Creative Suite products – but beyond that there are few joint interests.
I wanted to jot down some of our thoughts on Adobe’s Flash products so that customers and critics may better understand why we do not allow Flash on iPhones, iPods and iPads. Adobe has characterized our decision as being primarily business driven – they say we want to protect our App Store – but in reality it is based on technology issues. Adobe claims that we are a closed system, and that Flash is open, but in fact the opposite is true. Let me explain.
First, there’s “Open”.
Adobe’s Flash products are 100% proprietary. They are only available from Adobe, and Adobe has sole authority as to their future enhancement, pricing, etc. While Adobe’s Flash products are widely available, this does not mean they are open, since they are controlled entirely by Adobe and available only from Adobe. By almost any definition, Flash is a closed system.
Apple has many proprietary products too. Though the operating system for the iPhone, iPod and iPad is proprietary, we strongly believe that all standards pertaining to the web should be open. Rather than use Flash, Apple has adopted HTML5, CSS and JavaScript – all open standards. Apple’s mobile devices all ship with high performance, low power implementations of these open standards. HTML5, the new web standard that has been adopted by Apple, Google and many others, lets web developers create advanced graphics, typography, animations and transitions without relying on third party browser plug-ins (like Flash). HTML5 is completely open and controlled by a standards committee, of which Apple is a member.
Apple even creates open standards for the web. For example, Apple began with a small open source project and created WebKit, a complete open-source HTML5 rendering engine that is the heart of the Safari web browser used in all our products. WebKit has been widely adopted. Google uses it for Android’s browser, Palm uses it, Nokia uses it, and RIM (Blackberry) has announced they will use it too. Almost every smartphone web browser other than Microsoft’s uses WebKit. By making its WebKit technology open, Apple has set the standard for mobile web browsers.
Second, there’s the “full web”.
Adobe has repeatedly said that Apple mobile devices cannot access “the full web” because 75% of video on the web is in Flash. What they don’t say is that almost all this video is also available in a more modern format, H.264, and viewable on iPhones, iPods and iPads. YouTube, with an estimated 40% of the web’s video, shines in an app bundled on all Apple mobile devices, with the iPad offering perhaps the best YouTube discovery and viewing experience ever. Add to this video from Vimeo, Netflix, Facebook, ABC, CBS, CNN, MSNBC, Fox News, ESPN, NPR, Time, The New York Times, The Wall Street Journal, Sports Illustrated, People, National Geographic, and many, many others. iPhone, iPod and iPad users aren’t missing much video.
Another Adobe claim is that Apple devices cannot play Flash games. This is true. Fortunately, there are over 50,000 games and entertainment titles on the App Store, and many of them are free. There are more games and entertainment titles available for iPhone, iPod and iPad than for any other platform in the world.
Third, there’s reliability, security and performance.
Symantec recently highlighted Flash for having one of the worst security records in 2009. We also know first hand that Flash is the number one reason Macs crash. We have been working with Adobe to fix these problems, but they have persisted for several years now. We don’t want to reduce the reliability and security of our iPhones, iPods and iPads by adding Flash.
In addition, Flash has not performed well on mobile devices. We have routinely asked Adobe to show us Flash performing well on a mobile device, any mobile device, for a few years now. We have never seen it. Adobe publicly said that Flash would ship on a smartphone in early 2009, then the second half of 2009, then the first half of 2010, and now they say the second half of 2010. We think it will eventually ship, but we’re glad we didn’t hold our breath. Who knows how it will perform?
Fourth, there’s battery life.
To achieve long battery life when playing video, mobile devices must decode the video in hardware; decoding it in software uses too much power. Many of the chips used in modern mobile devices contain a decoder called H.264 – an industry standard that is used in every Blu-ray DVD player and has been adopted by Apple, Google (YouTube), Vimeo, Netflix and many other companies.
Although Flash has recently added support for H.264, the video on almost all Flash websites currently requires an older generation decoder that is not implemented in mobile chips and must be run in software. The difference is striking: on an iPhone, for example, H.264 videos play for up to 10 hours, while videos decoded in software play for less than 5 hours before the battery is fully drained.
When websites re-encode their videos using H.264, they can offer them without using Flash at all. They play perfectly in browsers like Apple’s Safari and Google’s Chrome without any plugins whatsoever, and look great on iPhones, iPods and iPads.
Fifth, there’s Touch.
Flash was designed for PCs using mice, not for touch screens using fingers. For example, many Flash websites rely on “rollovers”, which pop up menus or other elements when the mouse arrow hovers over a specific spot. Apple’s revolutionary multi-touch interface doesn’t use a mouse, and there is no concept of a rollover. Most Flash websites will need to be rewritten to support touch-based devices. If developers need to rewrite their Flash websites, why not use modern technologies like HTML5, CSS and JavaScript?
Even if iPhones, iPods and iPads ran Flash, it would not solve the problem that most Flash websites need to be rewritten to support touch-based devices.
Sixth, the most important reason.
Besides the fact that Flash is closed and proprietary, has major technical drawbacks, and doesn’t support touch based devices, there is an even more important reason we do not allow Flash on iPhones, iPods and iPads. We have discussed the downsides of using Flash to play video and interactive content from websites, but Adobe also wants developers to adopt Flash to create apps that run on our mobile devices.
We know from painful experience that letting a third party layer of software come between the platform and the developer ultimately results in sub-standard apps and hinders the enhancement and progress of the platform. If developers grow dependent on third party development libraries and tools, they can only take advantage of platform enhancements if and when the third party chooses to adopt the new features. We cannot be at the mercy of a third party deciding if and when they will make our enhancements available to our developers.
This becomes even worse if the third party is supplying a cross platform development tool. The third party may not adopt enhancements from one platform unless they are available on all of their supported platforms. Hence developers only have access to the lowest common denominator set of features. Again, we cannot accept an outcome where developers are blocked from using our innovations and enhancements because they are not available on our competitor’s platforms.
Flash is a cross platform development tool. It is not Adobe’s goal to help developers write the best iPhone, iPod and iPad apps. It is their goal to help developers write cross platform apps. And Adobe has been painfully slow to adopt enhancements to Apple’s platforms. For example, although Mac OS X has been shipping for almost 10 years now, Adobe just adopted it fully (Cocoa) two weeks ago when they shipped CS5. Adobe was the last major third party developer to fully adopt Mac OS X.
Our motivation is simple – we want to provide the most advanced and innovative platform to our developers, and we want them to stand directly on the shoulders of this platform and create the best apps the world has ever seen. We want to continually enhance the platform so developers can create even more amazing, powerful, fun and useful applications. Everyone wins – we sell more devices because we have the best apps, developers reach a wider and wider audience and customer base, and users are continually delighted by the best and broadest selection of apps on any platform.
Conclusions.
Flash was created during the PC era – for PCs and mice. Flash is a successful business for Adobe, and we can understand why they want to push it beyond PCs. But the mobile era is about low power devices, touch interfaces and open web standards – all areas where Flash falls short.
The avalanche of media outlets offering their content for Apple’s mobile devices demonstrates that Flash is no longer necessary to watch video or consume any kind of web content. And the 200,000 apps on Apple’s App Store proves that Flash isn’t necessary for tens of thousands of developers to create graphically rich applications, including games.
New open standards created in the mobile era, such as HTML5, will win on mobile devices (and PCs too). Perhaps Adobe should focus more on creating great HTML5 tools for the future, and less on criticizing Apple for leaving the past behind.
This will (hopefully) be a start to a series where I take a look into various devices and analyse them. My intention is to begin with very simple devices and steadily ramp up to more complicated ones as time goes on. The idea is to give the reader enough information about the device (design, function, components, etc) to the point that they can conceivably create their own. As well as in some cases recommending certain modifications, tools, adapters, or companion devices for optimal practical use.
Device information
This is a resistive load with a male USB plug interface. It’s intended function is for testing the current output of USB power-supplies and power banks. It has 2 current draw settings, these include: a 1 ampere and a 2 ampere mode. This device is operated using a two state slide-toggle switch, which allows alternating between the two current draw modes. Additionally it uses a common anode bi-colour LED as an indicator for these modes. Green for the 1 amp and red for the 2 amp mode.
The general layout and configuration of the 5 ohm wire-wound power resistors is what makes this device function. One resistor (R1) is always in circuit, in both the 1A and 2A mode. Within the 2A mode, R2 is added (in parallel to R1) to the circuit. Adding R2 in parallel to R1 reduces the circuit resistance to 2.5 ohms, which in turn draws 2 amps from the power supply.
1A mode: R1 in circuit (5V/5R=1A) 2A mode: R1 and R2 in parallel (5V/2.5R=2A)
3-state switch or additional switch (for device OFF state)
Heatsink / fan (to efficiently dissipate generated heat)
PTC resistor (as a safety temperature cut off)
male USB to female USB extension cable (for allowing easier multimeter access)
Additional switch
Due to both states of the USB resistive load’s two-state slide-toggle switch being used during the operation of the device, the device has no plugged-in OFF state. This means that it should not be left unsupervised whilst plugged into a power-supply as it would be active at either switch state. Either adding an additional two-state switch or replacing the current one with a three state-switch, will allow the device to have an OFF state. Whether or not this is considered valuable, is largely subjective. However personally, I like the option of turning a load off without necessarily having to unplug it.
Heatsink and fan
The reason why leaving this resistive load active and unsupervised is a concern; is predominantly due to the functioning of the two large 5 ohm power resistors. These resistors dissipate around 5 watts each (5V*1A=5W) and generate considerable heat as a result. Because of this, I recommend the addition of an appropriate heatsink to be attached to these resistors in order to dissipate this resultant heat. As it is now, during continuous operation the resistors heat up to the point that they can not be handled with a naked hand. This level of heat could pose a possible burn risk, or fire hazard.
The addition of a heatsink will allow the device to run continuously without reaching these same high temperatures, it does this by dissipating the heat generated within the resistors in a more effective manner. I.e. moving it into the environment quicker, so that it doesn’t concentrate within the device. An addition of a mounted 5 volt mini fan will enable the cooler ambient air to run through the fins of the heatsink and further improve it’s ability to move heat out of the device. I specify a 5 volts fan because it can be powered from the device itself.
In addition to allowing the device to be handled after extended periods of operation, a good heatsink will in all likelihood also extend the lifespan of the two 5 ohm power resistors. It does this by dissipating any generated heat before it reaches levels that may damage either the components themselves or their neighbours. Generally speaking: devices that run cooler, live for longer.
PTC thermistor
As an alternative to the above two fairly common sense modifications; one could also choose to incorporate a Positive Temperature Coefficient (PTC) thermistor as some kind of safety shut off in the cases where the device reaches any critically high temperatures during operation; essentially as a reusable temperature fuse. The reason why I am dubious in recommending this is that: although it will make the device safer to use in a continuous application; attaching a PTC thermistor in series with the two power resistors may actually affect the resistive load’s performance if not it’s ability to function entirely. I am not sure as I am inexperienced with the application of thermistors in general, and have yet to try this particular use-case out.
My working theory is that since a PTC thermistor increases resistance as it heats up, and with this device’s current draws; it will quickly lead to a positive feedback loop where it’s resistance generates heat, which will generate more resistance, and so on until no current can pass through it – essentially becoming open circuit. I believe that the heat generated from the low resistance power resistors will kick start that sequence; and that the increasing circuit resistance from the PTC thermistor will quickly negate the the power resistors’ ability to draw current. Even if the thermistor’s resistance doesn’t increase to the point of open circuit. It only needs to be consistently higher than the power resistors’ 5 ohms in order to hamper device functionality.
Still, perhaps there is a configuration where the PTC resistor will not negatively affect the power resistors, while still being functional as a thermal fuse. Perhaps if the trip temperature of the thermistor was high enough, or it had a position on the device where it only heated up in cases of catastrophic environmental temperatures. Basically a setup that allowed for the added safety of having a thermistor in circuit without it negatively affecting the functionality of the device.
USB extension cable
I decided to create my own USB extension cable rather than use a prebuilt one. The main reason for this is that I fear that a random off the shelf unit my not be designed to handle current draws of 2 amperes (even if it’s vendor says that it is). This would mean that the cable itself would provide a level of resistance that would become a limiter to the amount of current that the resistive load can draw.
Generally if a USB cable is offering resistance, it will be in it’s cable and not in it’s plug and socket. Either the cable itself is too thin of a gauge, made of inferior materials (aluminium instead of copper), or is long enough to cause voltage drops at higher currents. With this in mind, I used thick gauge copper power cables (taken from an extension cord), and a salvaged USB plug and socket. I also made sure to keep the total length of the cable short; just being long enough to allow comfortable use of a clamp style multimeter.
Which actually brings me to the purpose of this little extension. The pictured USB extension cable is designed to allow the use of a clamp multimeter (one that can measure DC current). Alternatively, if I didn’t have a clamp multimeter, I would cut the 5 volt line in half and terminate it’s two ends with banana plugs. That way I can insert a regular multimeter in series within the circuit; and measure the actual current draws.
As an alternative to using a DIY USB extension and a multimeter, one could just buy a USB voltmeter/ammeter. Such as the one pictured. Although these things, in my opinion can skew the results: due to them (in my experience) imparting some level of resistance on the circuit; they are certainly more convenient to use. Which one a person prioritises: accuracy, or speed (neatness, etc.) will largely depend on their preferences and use-cases.
Closing statements
Although the build quality of this device is more than acceptable (i.e. it doesn’t feel like a shoddy product), it is clearly built to a price point. Only having near enough the absolute necessary components to function. I believe this to be the case, not just because of the miniscule bill of materials (BOM), or the use of inexpensive components in that list. But rather because of the in my opinion necessary things that were left out; namely a basic heatsink.
Although it actually functions fine as is; at least for short operations. If you wish to use this device safely continuously for longer periods of time than a couple of minutes, modifications will need to be made.
