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- เผยแพร่เมื่อ 1 ต.ค. 2024
- Teardown Tuesday.
Dave tears down a cash register found in the dumpster.
Does it have any useful parts to salvage?
German brand Quorion QMP 3282
And a look inside a thermal print head.
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I would love to see a photo of Dave inside the dumpster with just his knuckles over the top edge and the very top of his head/eyes looking out. Too funny. Like, "Kilroy was here".
Would make a great thumbnail!
EEVblog that it would
lets try to make one :)
Scanner = bar code scanner?
Yes, indeed.
Toilet paper dispenser with a cutter mechanism.
Electrical tape slicer?
Exactly what I thought of too! LOL!
yes...with kids...we go through a roll of TP a day because they use WAY too much..
dude! my exact thought!!
Try teaching them to fold it intead of just scrunching it up into a ball. Helped lower my usage greatly once someone told me to do it like that ( That was at about age 6)
The EEVBlog, Teaching people how to rob cash registers since 2014.
yep, I might check for that the next time I do work on a credit card machine (the place I work had the PoS separate from the credit card machines)
I like to cater to all audiences.
EEVblog
And that's why I'm a subscriber. Thanks Dave.
The shop i work in had a release button on the till but it had to be covered as it was part of a compliance audit we usually just taped a cd cover over it, though most modern ones will have the power loss release built into the keyhole, centred unlocked, turn right to lock and left to release the drawer
I like the idea of reverse-engineering the display interface :-)
Hey Dave I think this would make a nice video. Perhaps with a fundamentals Friday about logic analyzers and different protocols in general.
If you're the same opinion leave a comment or a thumbs up to make Dave aware of.
I'll see what I can do.
Auto Toilet paper cutter!!!
Make it Arduino controlled and it'll hit the front page of Hack-A-Day!
EEVblog The problem there would be, that you need something to hold the paper, otherwise it would fall down as soon as cut. OR it will only cut the paper the instant you pull it, basically making the pulling even easier... Well... Somehow interesting Idea :D
Maximilian Mustermann It would not fall. If you look carefully at the cutter, at the top of the "V" shape there is a notch where paper is not cut. It stops the receipt falling from the machine :)
chris746568462 oh, nice :D but would that be enough to hold back multiple sheets of toilet paper?^^
Maximilian Mustermann For "Heavy" Users, probably not lol!
Hi Dave! Long time viewer, first time commenter, I have used many different cash registers:
1. yes, they all have some dingy tab to open the drawer, but only if it is unlocked (it only overrides the solenoid)
2. The key you found is for changing the mode, not locking the drawer. The modes are normally: Program, normal, void, off. one key (user) will let you turn it on and off, the other (admin) will let you program it and void sales. This is why it is not a really secure key.
3. programming these things is only slightly better then a root canal;
Put in PGM mode
enter 1001 press PLU then 1100 press PLU then AM/TD
Enter 1011 Press PLU then turn gey to Void and press AM/TD
and so on and so on. it is horrible.
I've heard that most places don't actually keep any money in their cash registers after they shut down for the day, so the fact that the register wasn't secure probably wasn't actually a problem.
Dave, I would be interested in a episode dedicated to "the art of the bodge." Like what exactly were the symptoms before the mod, how easy is to replicate the failure, why the problem wasn't identified before production, the costs involved, the terror, finger pointing and other drama behind the scenes when you suddenly discover you just 10,000 units that don't work, etc.
Every time I see a bodge on a board, I can't help but think "Man, somebody had a BAD day!"
More like a bad week or month. These things often aren't detected and a solution found in a day. Then yes, all the finger pointing, the endless meeting to determine the best course of action etc. Then some poor bastard has to sign off on the mod again. That's real world engineering.
EEVblog
Are SMD bodges like that common? I've never seen that before.
watch the EEVblog #10, Dave tells a story when a bad rubber band cost one million dollars to a company.
excavatoree I spent a good part of last week soldering on 0603 resistors vertically on other smd component legs. Then run a little wire from the end that's sticking up for a discrete and fairly neat bodged pull up.
It would have been nice to see the power up sequence, as you described it was quite interesting. Also the software on those devices is at-least as important as the hardware. It's nice to see how displays are used ,how bright, character set etc, and it's nice to hear how piezo sounders are used. "Don't turn it on take it apart" only works when you reassemble the device and power it up afterwards :-). A tear down on dead device is only so interesting, if it's broken of course there no choice. Thanks for posting.
A non-contact toilet paper dispenser.
That cutter assembly could make quite a nice tape dispenser for PVC or Kapton, for those times when you need three hands.
or any big teeth sawblade
wayback old cash registers used to be a way of getting a cheap uc training system, when the very first casio electronic registers (more basic than that one) started getting dumped (mid 80's ish) someone had produced a prom with a monitor program on it which you sent off for to an address in an electronics magazine advert - pre youtube hack!
you had to assemble your machine code by hand and type it in through the keypad byte by byte, the VFD was your visual display and iirc there was no long term storage for your work. We had one at school - it worked but you only had about enough time to flash a led before it had to get switched off again at the end of a lesson. by that time a lot of kids had BBC and sinclair micros at home anyway which made it seem pretty unimpressive.
sorry for waffling up an old vid, just thought the people who've grown up on arduinos etc might be interested
the circuit board on that looked surprisingly clean given it had been used in a cafe
Dave, your comments about bodges on this German product are much more measured than your screams when you see bodges on Asian stuff. The PS is looks really good though.
I love the Tek USB stick beside the scope at the back!
I have used thermal printers before for some fun wankey little projects ... twitter reader, joke receipts, printing out small things ... i stuck a little ATMEGA32u4 breakout in one and put it in a nice box ... unfortunately broke when my power supply failed!
im most excited by that VFT ... i absolutely LOVE VFT displays but there soooo expensive!
Keep a eye on the noritake-itron sample site. They have very reasonable prices and often offer substantial discounts (50% off at the moment). Their evaluation kits are first class with excellent documentation and pre-made libraries.
Thanks allot!
some dvd players have VTF displays
More useable parts than a inkjet printer!
toilet paper cutter :D
moar ferrites! XD
also the cutoff mechanism is a must for a microcontrolled toilet paper dispenser ;)
Probably too flimsy to be effective on toilet paper. Well, unless you buy the cheap stiffer crap.
I'll gladly give this teardown a Thumbs Up & a Kerchinng!!! for added value. :)
Personally I mostly salvage motors from my tears downs even though I rarely use them.
Motors are just such nice things. Hard to toss out.
Why are the parts offset on the power supply? I thought wobbly parts are bad?
In a fixed product like this it's fine.
Idea for the paper cutting mechanisem: Full auto toilet paper cutter.
all cash registers have that little button at the bottom
JydenStudsgaard so does mine, i have one in my claw machine in my oom
Just curious, do you ever try to recycle surface mounted parts? I have to drive 10 miles to get a cap that I could probably rob out of an old VCR! (16k? Yeah I know. I'm trying to get us on metric, but I have to convert myself too, and that's hard!)
Yeah, if I need something right then and there I'll salvage old board. This is why I keep them.
Repurpose the receipt cutter into an automatic foreskin circumciser.
Would be hilarious if there was any money left in it. :)
Very nice Dave!
I really love your teardowns, which i myself already did as a kid.
BTW, i think the cutter mechanism doesn't cut the paper completely, in the middle there would be a little spot left uncut. Then you would have a chain of receipts instead of a bunch of individual sheets of paper.
Keep up your style!
Was that membrane recycled from a rubber keyed Sinclair Spectrum? ;o)
LOL!, yes, it's Cheap Arse Technology Tuesday.
I want your dumpster
Make a packing tape dispenser with the cutter! :)
Any place I've ever worked at you can open a regester with a pen or your finger on the underside of the drawer
I've seen it on a lot of cash registers/POS systems too. I guess people always lose the keys, so they need a backup.
Your building throws out a LOT of electronic devices.
OMG the amount of finger crud on that keypad.
Can you do tutorial on vfd?
That's interesting; I didn't know that those little LCDs out of stuff like that could be useful again for other projects. How would you go about hooking one of those up to a computer and interfacing with it?
Here's a datasheet for a typical Thermal-printhead driver, it's quite simple! www.dropbox.com/s/bdtmfr2qdsdogkl/64-bit%20thermal%20head%20driver.pdf
Don't forget the solenoid! You can salvage that puppy too. I tore apart an old tape based answering machine and found 2 solenoids for salvage inside of that guy not to mention some of other useful parts.
i think a Facebook/twitter printer based on this printer and a raspberrypi would be awesome! Something that would print out every post of a specific hashtag :)
Would really, really love to see that! :)
Dave, check that VFD for severe burn-in, if it has been running static, which they usually do, re-purposing it will be a bit sad :/ - but try to document reverse-engineering the interface!
Hehe I should do some tear down videos of some stuff I have here.
There is something from goodwill that I got that does not work and want to ask if any one can figure out what is wrong.
Although I am thinking it is the Lazer as it skips pretty badly.
It is a 300 disc changer,
There is also an old coffee pot that I should tear into on camera as I wanted to try to fix it if I could.
As it was a fairly pricey coffee pot.
I just never have done anything with the coffee pot as it has freaking security bit screws holding it together. :|
This is really cool. As I work for military defense, all this "afterthought circuitry" is a real thing and hasn't gone anywhere! Sometimes we have to get a product out, and scotch tape and lead solder is the only way!
I had a couple of TEC registers i was given. Same model person thought maybe i could swap out things and make one wok, and do something with. Even though same model interfaces, etc were totally off. I scraped them. Printers in mine were like a dot matrix setup of sorts. A row of solenoids that tripped these arms with i want to say the various characters on the end that ran by an ink ribbon and put the marks on the paper.
1:12 That's what I call teardown.
If I had all the equipment you have, I would probably reverse engineer the hell out of it, the thermal printer, the vacuum display... hope to see something like that. cheers :)
You can use the thermal printer to make a mini teletype computer running a Tiny BASIC! That would be an awesome project!
hmm, All cash registers are Korean made now by SAM4S!!
great video, interesting to see inside this unit!
Cool teardown, Dave! Tanx for this one. I like the VF Display best, as it is a very big one...;)
Very interesting ! In the shop were i am working we use small battery-operated thermal printers to print out price stickers and such. I believe that on the inside they should be looking like the one in this video, But they definitely have less DPI.
Those cheap membrane panels last 10's of millions of cycles in a dry environment. . . . VARTA BATTERY!!!!! KILL IT!!!!! KILL IT!!!!!
So many bodges on this device. More than any other you've shown. Several near the battery as well.
I work with Quorion machines, this one is very old, the new ones are much better, there's also a few of point of sale touch screen systems they have out, much better stuff. IF you need more info, check quorion.de :)
The drawer reminds me of the ones from the Samsung ER-6500's, same layout and design.
Hello Dave. I'm working on a optical-encoder-based, self-adjustable, TTL Logic project for industrial automation. Any thoughts?
I want to thank you Dave for explaining the low-impedance ground return to avoid ground-bounce.. I have an FPGA project that bounces like a space-hopper when the data lines are pulsed and will look into this kind of work-around! (I think the chinese company that built the gate array board under spec'ed the bank-caps, but will try this as a first port of call) - Nice one! & Regards from the UK :D
20:05 it is quite nasty, actually..
Use the cash drawer for petty cash and a secret button to release the drawer. Then will have cast for the pizza ! Also Charles Kettering worked at NCR (Dayton, Ohio USA I think) and invented the electric cash register ! Latter he did the V-8 for the Cadallac and the self starter (killed the electric car). So I think the guy is a woman libist by giving woman a job with the cash register and a way to get to the job ! tjl
Before watching this vid I moded a 50w bulb with reflector into a 500w light with the same reflector
Hi Dave! New sub here, I love your channel, it's very interesting to learn more about electrical components within, well, electronics. I've disassembled everything within my household I'm comfortable with doing so as I'm becoming more and more excited and interested with working on the actual hardware within electronics. But quite honestly, I don't understand 95% of what your talking about. I want to learn more, but your stuff is too advanced. I'm curious as to if you'd begin a fun "soldering beginners video/day" for a lack of better words or maybe even turn your second channel into one? Haha, Never know right? Mainly to attract more new viewers like me. I'm sure you've heard of Kip-Kay, I'm not a huge fan of him although I am subbed to him because he makes some very interesting/easy/fun soldering or even "electrical engineering" work (I guess would fit no?) that's simple enough for everyone to do. The fact of the matter is, I can only watch so many of your video's (and that’s out of pure entertainment). So like me there must be many many others that are in the same situation as me. I like you (underline) and your video's, but at some point I'll need to follow someone else to actually start learning how to get to the point where you are now. Hope you will give this some honest consideration, and out of gratitude I'de be personally taking time to advertise this channel out of excitement for anyone new to soldering/electrical engineering to learn from. I say soldering though in my mind I'm thinking of creating my own circuit boards for use rather than fixing or buying. Just my lack of knowledge at this point. Hope you can change that! Thanks for the vlog and reading, hope to hear from ya! Thx
Break it! BReak it! FUCKING BREAK THE DAMN THING! Ahhgggg! Break it!!!!!!!!!!!!!
This video caught my eye, (though I do watch 90% of eevb anyway) because I have a love for cash registers, have always wanted to have one, only thing stopping me is I have zero practical use for one and my bedroo.... "lab" is already cluttered enough XD
I am from Germany and I am a little shocked about the quality of that "German Engineering". Dave showed that Prema multimeter made in Germany a few videos ago, which also was full of bodges. A shame! Is it all only marketing?
Having pulled apart many cash registers, I think your lucky this wasn't an ex Pub machine. Nothing like the stench of 10 years of stale beer and cigarette smoke.
I would ship you an old mechanical if they didn't weigh +500LBs (36 stone or so)
Any interest in an ancient supermarket scanner scale?
At 11:10 what are those two blobs of solder (?) just to the left of the L293D Quad Driver chip. This is a 1.2A peak device so lots of current - I can see the large traces to the connectors. Are the blobs to bridge some pins to handle the current?
I wonder how much of these 'bodging' is the result of keeping the same kind of product running for many and many years with installing new and more modern options and changing parts.
I have taken aparta kind of simular looking machine many years ago, some parts like the power-system are different, but some other parts are more or less the same or might be compatible.
Like in supermarkets (where mine came from) they used to have a very long life with replacement-boards 'on the fly, same day repairs', connecting the newer stuff and it was running again and the serviceman goes to the next shop. They can be in use for over 20 years when the supermarkt doesn't need or want new functionality.
One of the things that changed in the life of these things were the printer and the printerboards. First they were not even thermo but with a small ribbon on 2 paper-rolls: one for the shop (roll staying in the machine) and one for the customer. Later they changed the system for saving the data internally in the registr., digital so you can print it out or safe it dayly instead of (only) the paper copy. That could be done in the same register, only 'swap out' the printer and the board.
Here at least they used to be emptied and counted at leas once a day, sometimes an exchange midd-day with other people starting to work. The chef usually had the key for all functions (like changing price) and the normal 'register-girls' just used a key with little functionality (selecting, scanning and paying).
Nice teardown.
For about 10 years i've used an ex McDonald's cash drawer in my bedroom to store things like spare keys, cigarettes, a bit of cash, screws and other random small things. I drive the solenoid with 12v, with a button hidden nearby.
It doesn't have a finger release but the lock is so easy to pick that you could probably do it with one bobby pin.
I guess cash registers don't really need to be very secure because if a staff member wants to steal money they can always just open it. And if someone robs the place they could often just take the whole drawer or have a staff member open it.
2:41 lol, what the fuck?
Turn the thermal printer head into a FLIR persistence of vision display? Delightfully impractical :-)
So... the key mechanism is just for show. Leave it to the Germans to secure currency.
+EEVBlog would you like me to send a busted multimeter Down your way? (Does the +EEVBlog thing work?)?
That tray's not locked then. You've just bypassed the button to open it. When locked, there's a metal bar preventing it from sliding out.
This guy clearly doesn't know what he's talking about. That circle dill on the middle between the left was obviously a flux capacitor.
On the under voltage bodge at 8:06, is there a chip resistor between the left hand and middle lead of the Motorola device? Wow. Aside - The 8:06 above becomes a link to the correct spot in the video! That is why this is a repeat to change the time stamp. Very nice TH-cam!
Thermal printers are a good output device for projects using a raspberry pi or arduino. I wouldn't bother with one unless it had an rs-232 interface though.
When I worked at my dad's restaurants, all the cash registers had the option to open the drawer manually. The mechanism is always stick your finger in the back, on the bottom of it. Normally the register is against the wall, and is heavy due to the weight of coins in it, so it is not easy to raise it and open it, but when you need to, you can. When will you need to?, easy: when you have no electricity, and a customer comes in, and of course you have handy the manual paper invoices.
The cash register is not a safe box replacement.
I'm gonna go join the eevblog forum because I actually want to be part of your community. I have so many questions, and I don't want to keep bothering you.
for those wondering about the mode switch, the x is for a running PLU report (usually an hourly report) that does not clear the stored PLU information. The Z mode prints out a report of every item from the last time a Z was done, and it clears out the information. Not sure about the other modes, but X and Z are pretty standard for PLU tracking systems
I would really like to see what you make from all of these dumpster dive component saves ! Would be great to see you build something free and useful out of all these saved and re-purposed items. :-)
That paper cutter ? Perfect for a fully automatic toilet paper dispenser! Just wave your hand in front, TP rolls out, gets cut and you don't have to do all that hard work manually!
Thank you so much! I finally found out how to separate the top part from the bottom drawer! Excellent! So, I can now use only the drawer while I take the top part to fix.
You could of sold that cash register, they can fetch a few hundred bucks.
You could of sold that cash register, they can fetch a few hundred bucks.
The key lock was actually not locked, the drawer just will stay closed unless you finish a transaction or press the manual release. If the drawer was locked, neither would have worked.
Might be interesting (and karmically appropriate) project to combine this with the laser barcode scanner and turn it into a shopping list generator. Wave a product you've used up at the scanner and it stores it with a microcontroller and then with touch of a button it could print up a shopping list of what you need to re-stock.
Don't know why I subscribed after seeing this vid, maybe his passion for these thing we take for granted, I'm not sure but it entertained me, and I think I learned some thing?
Thanks for the tear downs! I enjoy ever single one of your videos. First the scanner and now the register, complete convenience store package.
casio made the best registers. they were a pain in the ass to program, but they had so much functionality for PLU tracking. good times
The thermal printer can be used as a roll-mode oscillograph. Saving low frequency wave or data on paper.
128 or 256 lines per ic on the print head... std bit rates... maybe minus 1... 127 or 255...
Was the printer return ground through the logic board still connected or had it been cut?
I have an Idea for the paper cutter ... I think it would make a nice toilet paper cutter for those mornings when you just don't have the energy to tear off a piece of TP
Argh, his voice is soooo grating! I couldn't listen to it for 5 minutes... :(
gotta love teardown tuesdays!! i would love to see the reverse engineering of that VFD, i have two of them from VCRs and i have been meaning to use them
I don't really get what is going on in your videos, yet I still watch them. Wonderful.
i'm working making embedded software for cash register -_-
Automatic toilet paper cutter?
Also I love your videos. They have helped inspire me to pursue a career in engineering.
Was that a surface mount resistor soldered between the leads on the reset chip?
You could use the printer for a bitcoin qr code vending machine. Prints out qr codes so people can scan them in with their devices.
Use the cutting unit to make a packaging tape dispenser. Maybe you could have Sagan help you
On the under voltage bodge at 8:40, is there a chip resistor between the left hand and middle lead of the Motorola device? Wow.