EEVblog

Рет қаралды 181,152

Күн бұрын

How to hack a calculator into a test system event counter.
Previous video on contact debouncing and using a universal counter: • EEVblog #961 - Monkey ...
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@zer0b0t 7 жыл бұрын

Hacking anything, that's the kind of content I really like to see.

@zer0b0t 7 жыл бұрын

Ugh?

@thelavian4481 7 жыл бұрын

You often tell random people what to do?

@arcade_signal 7 жыл бұрын

I think he meant hacking in the original technical sense and not in the "soft" sense where the word has been co-opted by morons and applied to silly stuff. It's even been bitten by marketing people, search for "growth hacking" to discover a new and exciting world of idiots

@electronicsNmore 7 жыл бұрын

I did the same thing using one of those inexpensive tally counters. Worked great with the magnet and reed switch.

@PiratCarribean 7 жыл бұрын

I read "Hacking A Calculator Into A Calculator" 😂

@anotherdayisforever 7 жыл бұрын

One of my favorite DIY vids youve ever done!

@NoxMarcus 7 жыл бұрын

Dave is SO prepared to demolish the Batterizeroo. Got all the toys lined up, I love it. I don't care about the actual device itself. But all this stuff showing how to accurately disprove the b.s. is really interesting.

@kryskarr23 7 жыл бұрын

Cool tutorial. Big fan. Take care and keep up the quality work.

@orvillejones1258 7 жыл бұрын

Nice project Dave, thanks for sharing!

@umajunkcollector 7 жыл бұрын

happy new year dave, good one Don

@NicholasAarons 7 жыл бұрын

That Was Awesome Dave. Keep up the great work. Nick.

@nickhill9445 7 жыл бұрын

Love the idea. Another possibility is to put the reed switch inside the calculator case. It can read the train directly without affecting the calculator appearance, and you can use a solenoid placed near the calculator for other applications.

@DoRC 7 жыл бұрын

batterizer test setup!!

@samgab 7 жыл бұрын

PS, you can also hack a cheap pedometer to do the same thing as this. They just have a little weight and switch inside which increases the count by one ever time the weight moves and closes the contact. You just remove the weight and solder wires to the two contacts and then you can connect those wires to any switch, such as a reed switch and magnet or a light sensitive switch, etc.

@mattshilling 7 жыл бұрын

Samgab Better solution!!

@rpc72 7 жыл бұрын

Samgab was gonna post the same comment when i saw yours.

@BendeVette 7 жыл бұрын

I used this when I was 18 (34 years ago) on my bicycle to count the distance of my trip. You could enter the circumference of the wheel and each rotation would add this to the previous result. Worked wonderfull. Magnet and a reed relay.

@TechGuyCharlie 7 жыл бұрын

Hi Dave, such a cool project there! Would have looked great with a VFD display calculator.

@linengmiao 7 жыл бұрын

More of such hacking video's please! It is a real pleasure to see you hacking/modifying and reverse engineering stuff (in stead of mostly just analyzing and explaining like we are used to).

@mbirth 7 жыл бұрын

I somehow expected you to seamlessly implant a calculator into a counter top …

@thevoid7480 7 жыл бұрын

Forshadowing the batterizer test setup. ;) But why not use an arduino for that? You can collect and store the data and send it to a PC. Then you could also implement a timer that measures how much the train slows down instead of just counting loops. Collect more data!

@rogerkerr5745 7 жыл бұрын

I saw this done by a couple of guys who wanted to count the number of turns when winding a motor. It was a brilliant simple hack which performed perfectly.

@ExStaticBass 7 жыл бұрын

This is definitely something I wouldn't have considered doing before watching this video. They say the simplest ideas are the best and this one is brilliant. I think I would put the connector in farther so the pins wouldn't stick out the side but that's the only thing I'd change. I loved the Keysight O-scope hack too which I just finished watching before this one.

@ralfgottfridhansson3127 7 жыл бұрын

Nice battery tester ! Happy new year!

@tambechristian 7 жыл бұрын

You are a genius Dave !!

@Zadster 7 жыл бұрын

Doesn't the calculator have an auto timeout? Unless you are watching it all the time, the little train will eventually stop, the key presses will cease and a few minutes later it will time out, losing the count number? The M+ button might have been a better option, as the contents will be retained.

@EEVblog 7 жыл бұрын

Good point. No issue for me as I'll be recording on video.

@therealjammit 7 жыл бұрын

I'm sure you could either buy enough cheap calculators until you find one that doesn't time out, or buy an old LED calculator on eBay. Pretty much any old LED calculator didn't have enough horsepower to do fancy things like power management. Might have to make an Ac adapter to replace the batteries.

@akuunreach3260 7 жыл бұрын

Nice Zadster, I was going to comment on the M+ being a better way as it keeps a perfect count vs the +1 Though Dave could just start with -1 so that the running total comes out correctly.

@suplerb 7 жыл бұрын

Zadster Whatt does M+ do?

@akuunreach3260 7 жыл бұрын

Mancobbler, it adds to what is stored in the memory. MS is memory store, M+ and M- add and subtract from the stored value, and MC clears the memory. So say you want to figure your pay but part of it is over time, so you take your hourly and multiply it by 40, and store it in memory. Then you would take your pay and multiply by 1.5 or w/e and then the hours of OT, and press M+ Now when you press MR (memory recall) it will show your pay for the week before taxes and withholdings. If you already knew some or most of this, I was simply trying to be thorough, plus others might read this post.

@Blendedasian 7 жыл бұрын

holey queen spikes, look at this fabulous smooth footage! Thanks, dave, you're making your videos way more pleasant to watch with 50fps. welcome to the pc master race club.

@MyBigThing2010 7 жыл бұрын

this is genius....I would never thought to do this on my own...I'm not that "creative" ...thanks for the idea, just saved me an eBay purchase, saved money and a month of time waiting for CE garbage to get here...all for the cost of a jst, a scrap of wire, solder dots and a few minutes of time! definitely gonna give this a go! THANKS AGAIN.

@billboe9784 7 жыл бұрын

Great video! Ive never seen a hardware calculator hack before.

7 жыл бұрын

Great post Dave!

@tomwimmenhove4652 7 жыл бұрын

I remember doing a project like this when I was around 6 or so. I connected one wire to our (aluminium) sink, and the other in a glass of water. By placing the glass below the tap and having it drip into the glass, the calculator would count the number of drops that have fallen. At the time I didn't appreciate the incredibly small change of current by the charge carried by a single drop. I'm still amazed that it worked at all :)

@TechsScience 5 жыл бұрын

This videos deserves millions of views

@danielmoraes9637 7 жыл бұрын

Great job!

@andrewsalton7670 7 жыл бұрын

simple,cheap and reliable. nice one.

@ravivashatkar5585 7 жыл бұрын

I had the same idea Dave .... I never tried it .. thankyou for doing this 😊😊😊👍

@genericgreensquid6669 7 жыл бұрын

This was helpful!

@faybercova 7 жыл бұрын

what amazing video, congrats

@travis4798 7 жыл бұрын

I use to mod electronics in the past. Best wire to use for pads is computer ribbon cable and if you go online to say Amazon they have ribbon cable by 20-50 foot rolls. Solder on with low heat, tack down in a few spots using hot glue, it will never come off.

@doggy_888 7 жыл бұрын

WOW it's a really cool project!!!

@krzysztofsoja5301 7 жыл бұрын

Back in a days I used this method to make distance couter for my bike :)

@aserta 7 жыл бұрын

I used one of those electronic finger counters. Works perfectly well for those who don't want to do complex things.

@abymohanan2043 3 жыл бұрын

Thank you so much for this video 👍🏻👌🏻✌🏻

@petermuller608 2 жыл бұрын

Having a toy train: nerdy Using a calculator to manually count the laps: nerdy Hacking the calculator to count the laps of your toy train: king of the nerds xD

@SlyPearTree 7 жыл бұрын

I used that trick to make a cheap digital voltmeter in the 80's. If I remember it counted how many fractions of second acapacitor needed to charge from 0 to the same level as the voltage being measured (or discharge from measured voltage to 0). The fractions of second were probably relatively large since the calculator could not respond that fast, that was probably due to internal debouncing of the keyboard circuit. I think I took the idea in a magazine. The result was not really seriously usable but made a nice little experiment to learn a bit more about electronic.

@fdjhrfgjry 7 жыл бұрын

Hey Dave, another great feature of this ghetto-counter is that you can determine the +1 amount so flexible, eg. if used in composed counting formulas and tailor them (other than 1;) to match your purpose or eg. 6 decimal position or better precision. Almost literally a streetwise universal counter ;)

@Zamsky39 7 жыл бұрын

I really like videos like this one.

@tonesoft1956 7 жыл бұрын

New this when I had my first Casio calculator in the late 70s :D

@RPBCACUEAIIBH 7 жыл бұрын

If you press "+" then "1" instead of "1" then "+", then it starts from 0 not from 1 works the same way. You can also type in an initial number, from which to start counting, then "-" and "1" to count down, you can also use another numeric constant instead of "1" to count by that numeric constant.

@shawn_2 7 жыл бұрын

Super cool!

@bornfe5127 7 жыл бұрын

wow now ive got a counter for inductor and transformer projects thanks dave ("beauty')

@welshgoldferret5107 7 жыл бұрын

Awesome, I remember doing this when I was making Tesla coils on my homemade winding machine, worked well.

@mescalinum 7 жыл бұрын

Very clever trick! Thank you. Would using an OTA (like the LM13700, which has an example for voltage-controlled resistor) do the job for triggering the "=" key with a digital input, or it is an overkill? Perhaps you could achieve the same with a MOS?

@mirkomueller3412 7 жыл бұрын

Nice Idea - might come in handy someday.

@mooncabbagere 7 жыл бұрын

This week on EEVBlog's The Dave Jones Show, Dave hacks a calculator to count automatically!

@oogie-boogie 7 жыл бұрын

just a question,,, i bought a hakko soldering station,, ,, but i need to know what size tips to get?,, what do you use size wise,, thanks im trying to learn to solder well,,,lol,,and not suck at it :)

@RinconingenierilEsp 7 жыл бұрын

I love it, thumbs up

@ryangriggs5767 7 жыл бұрын

Very nifty idea! I wonder what the maximum input frequency is? (probably some multiple of the key matrix scan rate?)

@horiamorariu 6 жыл бұрын

Genious! Just remainds me that in a very old TEHNIUM (Electronics Magazine), back in 1980, in Romania, there is an article of WINDING MACHINE COUNTER - exactly the same, but based on Texas Instruments TI30. Nothing new under the sun. But maybe for some young hobbysts is new. Cheers Dave!

@dheujsnrhfydhehehshshhdggsd 7 жыл бұрын

really enjoyed a simple kid friendly project

@MisterTalkingMachine 7 жыл бұрын

We used to do calculator adding races in school this way.

@88njtrigg88 7 жыл бұрын

Can be used also for a home made anemometer project, with the addition of a stop watch.

@waynerussell6401 7 жыл бұрын

I had a client who wanted to detect how often a reference book was used. I embedded a watch module in the spine with reed switch and magnet and mode to set minutes. Only counted to 60 but that was adequate.

@techalyzer 7 жыл бұрын

I have done this on my bike ages ago, only instead of 1, I used to put in the tire's circumference to measure the distance.

@Crazytesseract 4 жыл бұрын

What's the difference in cost, if you use 4 bit 74XXX counter ICs in cascade, a bcd-to-7 segment convertor IC, and a few 7 segment displays, and wires, plus a bread board? And how do we latch the digits using multiplexing?

@cody5495 7 жыл бұрын

Question, if you were able to press the = button 1000times/seconds, could you overheat the calculator/max out the cpu? Do they have protections in place?..

@karlramberg 7 жыл бұрын

How fast switching speed will it keep track off ?

@MrJohn1966elliott 7 жыл бұрын

In 1984, I build it, use for "Odometer" fit my push bike. I put magnet on spokes bike wheel.

@rockets4kids 7 жыл бұрын

I recall an article on this from a magazine back in the 1980s. Does anyone happen to know the magazine/issue?

@IGBeTix-Electronique 7 жыл бұрын

Hi Dave, do you have the results for all these batteries ?

@antonnym214 7 жыл бұрын

Very nice! We can get these calculators at the Dollar Tree (everything's a dollar), so this is an awesome use for one.

@magista247 7 жыл бұрын

I did exactly the same 35 years ago with a Sharp calculator on my bicycle to measure the precise length to the basic school ;) So i was the first to have a 'bike computer'...

@BeetleJuice1980 7 жыл бұрын

what is the optimal "low" temp for these pads?

@SkylerF 7 жыл бұрын

I really need to drive multiple keys on a matrix-type input with digital logic. The problem with using a transistor is that it will only work with one key, because I can't use common ground. I know I can use optoisolaters, but is there any other way to electrically drive multiple keys with say several 5v logic lines, each for one key?

@SimonE-fz5pc 7 жыл бұрын

Funny found a box recently in the attic where my father did the same thing to count ants in a tube leading to food with a light switch for his Dr (PhD) thesis back in 1974! Sure it was an old "4 banger", as Dave says, but it still worked and high tech back in the days.

@FennecTECH 7 жыл бұрын

I would use lego and an solenoid to simply push the button each time lol

@RyanUptonInnovator 7 жыл бұрын

you forgot duct tape.

@FennecTECH 7 жыл бұрын

dont need duct tape when you use a lego flatboard as a base

@RyanUptonInnovator 7 жыл бұрын

I will attack your lego flatboard base with my duct tape x-wing fighters. Prepare your exhaust valve for my proton torpedos.

@FennecTECH 7 жыл бұрын

that sounds painful

@RyanUptonInnovator 7 жыл бұрын

At first it is like ow ow ow, but then it is oh oh oh. The worst bit is the child support.

@LA6UOA 7 жыл бұрын

Cool! Thanks, Dave! I really don't like tape. it falls off and in time its glue is a mess. Is there a reason why not use hot glue? and how fast is the calculator? Can it be used to count the rounds of say a propeller on a model aircraft? Love your channel!!

@tasteless_5915 2 жыл бұрын

If you get a knife down the middle of the plastic heat rivets you can “drill” them out as it separates the outer ring from it and you can’t take the chip out.

@pivendren 7 жыл бұрын

@EEVblog what was the reason for a different calculator at 2:15?

@tzisorey 7 жыл бұрын

I had a calculator as a kid, that had a little thumb-trigger "Count" button - so you could take tally of things easilly. Had one of those old light displays on it too - doubt it was LED, but some sort of low-power red 7-segment things.

@dismayer666 7 жыл бұрын

genius in simplicity :)

@thegreatdanet 7 жыл бұрын

What's the deal with the copper pads for J1? Using a blob of solder as a jumper?

@SpikesMavic 2 жыл бұрын

Fantastic, just what I need, am wanting to count the amount of turns of wire for a transformer

@brainndamage 7 жыл бұрын

I've used this method before for counting turns on a coil winding machine, the problem is that the calculator can only count so fast until it starts missing pulses. But for slow counts it is ideal.

@Zamsky39 7 жыл бұрын

How fast can the signal be for the calculator to be able to still catch up?

@inderpartapsingh4445 7 жыл бұрын

great sir

@Jones12ax7 7 жыл бұрын

as a kid in the 90s I used a crude switch on the front wheel of my bike and a hack like this. I type the wheel circunference, 2.1 at a time, and + so the I could measure the distance. I even placed a switch in a shoe to make a pedometer for a science fair of my schol. Good times before the microcontrolers invasion that we like so much today.

@EgoShredder 7 жыл бұрын

My uncle and I did something similar to make a digital speedometer for my bike around 1980 I think. We used little reed switches near the wheels to measure the speed etc. It worked perfectly and I was a proud kid, with lots of DIY gadgets! Good times :-)

@nrdesign1991 7 жыл бұрын

I made a bike pedometer that uses the AC voltage coming from the hub-mounted generator as a signal. It can't charge its battery through that yet though. I don't have any plans on working on it at the moment.

@maicod 7 жыл бұрын

as a kid I had a Fleischmann train and used 2 metal strips that when the train ran over it were pressed down and so the circuit closed and I let a railroad-switch flip over

@tin2001 7 жыл бұрын

I did the bike distance counter thing when I was a kid too. I wonder if I still have that calculator somewhere....

@kaziq 6 жыл бұрын

I once taped a switch (just two flat metal plates) to my heel, and wired it through the sleeve to an old bike counter stripped to my wrist. Then set an average step distance as the wheel circumference in the counter, and had a crude distance counter. And it was painful too after some time with the swith on my heel.

@BlankBrain 7 жыл бұрын

03:29 should'a used your Crocodile Dundee knife!

@blenderbuch 7 жыл бұрын

In the time as the four banger got cheaper we used this to make km counters for our bikes, enter the circumfence of your tires key in + + + + + + Or was it M+? I cant try only UNP Calcs here now

@frogz 7 жыл бұрын

heres a little hack for you, 301 green laser pointers(or any other cheap 18650 green laser pointer) aimed behind the board lets you see right through most circuit boards to see the traces

@JONOVID 7 жыл бұрын

IMO I would use hot glue to anchor wires in place. also I would use sockets as the wires end connectors so you can close the back up on the calculator and re-use for other counter type jobs in the lab.

@kajyakuzonik9130 7 жыл бұрын

Awesome! :D

@MisterBadNews 7 жыл бұрын

This is how we used cheap calculators back in '90 to count the number of coils on homemade coil winding machine. Using a calculator, a magnet and a reed switch attached to =.

@o1napstar1 7 жыл бұрын

I have a question: Why would you cover up the copper pads with carbon?

@gorillaau 7 жыл бұрын

Nice that the troll doll came along as a witness.

@moustafa19997 7 жыл бұрын

nice idea

@Zauviir 7 жыл бұрын

Is the batteriser fail train about to leave the station?

@Luclips123 3 жыл бұрын

Thanks

@Andrew_Sparrow 7 жыл бұрын

ive used the cheap dollar store step counters in a similar way, even easier to hack :)

@vehasmaa 7 жыл бұрын

i knew about constant mode but newer tought one could hack calculator to do it like that... Sure gives new usefulness to bargain bins 4-function calculators...

@jschroedl983 7 жыл бұрын

OMG I loved those thomas the tank engine tracks

@KevinOsborne1987 7 жыл бұрын

Joe Schroedl AKA 'Brio'

@bruhdabones 7 жыл бұрын

What kind of tape is the red tape you used? And, where do you get those stranded core wires?

@capitoliris5567 7 жыл бұрын

Bob dabiuld the tape is electrical (if i'm not mistaken) and the wire is wrapping wire (or mod wire). Very high gauge, good for this kind of stuff.

@Yrouel86 7 жыл бұрын

Seems normal electrical tape but you might also use a bit of hot glue. The wire is also called Kynar wire but for this particular application, especially if using a connector, you might also use some magnet wire (copper wire with enamel insulation) possibly recovered from somewhere (solenoid, motor, etc).

@Eicles 7 жыл бұрын

Annoying that there always has to be some dislikes; this is bloody brilliant! I'll have to remember this one, might come in handy! :-)

@billl605 5 жыл бұрын

Go green, power the loco with a solar cell, great video, and a thumbs up.

@Aleziss 7 жыл бұрын

speaking of carbon contact, what is the best way to fix rubber buttons that have their carbon contact not working anymore beside replacing the buttons ?

@techalyzer 7 жыл бұрын

I succesfully used tiny aluminium foil pads you can just cut with a hole puncher or scissors superglued to the carbon contacts on the rubber.

@Yrouel86 7 жыл бұрын

They might need just some cleaning with IPA (both button and contact) or a very light sanding (just pass the button a couple of time on some paper and then try it)

@Aleziss 7 жыл бұрын

+Ri Max ok, is that type of repair holding good for a long period ? it's for a remote control that is used everyday and button presses multiple time a day

@Yrouel86 7 жыл бұрын

If the problem is dirty contact it will last long enough I think (more or less as much time it took to get to where it is now).

@techalyzer 7 жыл бұрын

I haven't used it like that but I guess it should hold.