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Ask Slashdot: What Is Your Most Unusual Hardware Hack?
An anonymous reader writes: Another Slashdotter recently asked what kind of things someone can power with an external USB battery. I have a followup along those lines: what kind of modifications have you made to your gadgets to do things that they were never meant to do? Consider old routers, cell phones, monitors, etc. that have absolutely no use or value anymore in their intended form. What can you do with them? Have you ever done something stupid and damaged your electronics?
Using an expresscard PCIe breakout (and an ATX power supply) I have put a Nvidia GTX-780 GPU onto my 5 year old laptop. As an external accessory.
Works like a charm, and really makes this thing a high-end system again.
Probably using a simple webcam + multiple lava lamps and a bit of software written in java to create a true random number generator. Using the prng functions that most languages provide is so 1992.
Yes, I could have also used random.org, but I wanted to show my nephew how to code, and figured that would be an easy project for him to understand and us to have fun with.
Many moons ago, I got tired of what was on the radio, and I built a pirate FM station. It had a studio supplied with over 50 volunteer DJs, but most of all it had the transmitter up in the mountains, with a UHF uplink system, to allow for very broad coverage of our city. I made the uplink transmitter form a 1985 Motorola cell phone, the old brick type. It was suitably modified to put out wideband FM audio. You might be able to read about it by Googling "Radio Limbo Tucson".
The determined Real Programmer can write Fortran programs in any language.
I got a wakeup call once at 8am, it was my CEO whose Thinkpad laptop failed to boot due to a stuck CPU fan. He had a plane to board in 3 hours to visit a seminar where he had to present a slide stack.. the only copy of which was on that laptop. Naturally, there was no time to replace anything (much less find a spare fan), so after a short lecture on importance of backups I took his laptop, put my lips to the fan intake, pushed power button and gave it a gentle blow. That got the stuck fan started. Perhaps the same could be achieved with a dust blower, but we didn't have one handy. When he asked me how is he supposed to fix it in front of world's most known scientists in the field, I told him - "give it a blow on startup, that's all". Those EYES... It did the job though :)
Back in the 90s I still had a Commodore 64 with a MIDI controller that plugged into the joystick port. I made a homebrew cartridge with an analog sampler chip that plugged into the Commodore's expansion slot. All the parts came from Radio Shack, including the chip. I wrote a program that allowed me to record samples and control playback from a keyboard plugged into the MIDI controller. Eventually I intended to add options to save and load MIDI sequences.
Unfortunately, I was a little too cavalier while tinkering with the cartridge. After making a few tweaks to the circuitry in an attempt to reduce noise, I powered on the Commodore and immediately fried the motherboard.
I recently modified a simple doorway alarm, using an ATtiny85 microcontroller, to monitor two windows and two doors instead of the single door the original device was watching over. The alarm was powered by 4.5 volts which was perfect for the ATtiny, and it used a form of PWM signal for the piezo tweeter which allowed me to let the ATtiny produce different alarms to alert which of the four sensors was tripped.
I needed to connect two LANs across a street. We were sending data through our Internet connections, but our uplink speed was poor. I had two old wifi hubs, and converted one to a network bridge with an open source firmware. Used it to log into the other wifi hub, and created an 802.11G connection across the street. Took us 3 months to get permission to actually run a cable, so this worked until we were able to do it right.
Many years ago, a friend asked me to help him figure out how to find the code for his new car stereo (never mind how he obtained it). When it first powered up, you had to wait a few seconds and then press buttons for a 4 digit code. If the correct code was entered, audio would emerge. Rigged up a little board with a 16F84 (I think that was the part#), anyway controlled fets with wires soldered to the buttons for entering the numbers, created a simple opto-coupler with led and photo-transistor laying around and some tape. Used that to sense the audio output. Hooked a little lcd up to the mcu, wrote firmware to enter the code one-by-one and just stop and display the last number tried when the audio emerged. Took 4 days for the system to find the code because of the long wait time required between fet-controlled power ups. Worked like a champ. Wrote the code on top and handed it back to him.
Reverse engineered the Nintendo light gun (with the help of patents, purchased by snail mail, this was 1997). Soldered some wires to the inside of the Nintendo, connected them to the computer parallel port. Two of my friends and I wrote a Duck Hunt type game for DOS, just fitting under 640KB.
I was working on one of those gigantic 'motion theatre' fairground rides:
https://en.wikipedia.org/wiki/...
This was back in the era of 286 PC's - running DOS. The software was suffering timing issues and we really needed a hardware timer interrupt - but DOS already stole all but one of them - and we simply didn't have enough.
I needed a *roughly* 1kHz interrupt to monitor some ride function or other (I forget exactly what) - so I came up with the idea of putting a bent paperclip between the RxD and TxD lines of the RS232 port and using the serial port interrupt. I'd send a character out through the serial port - and at 9600 baud, with one stop bit and one start bit the character took ~1/960'th of a second to arrive back in the serial port chip...at which point it triggered an interrupt - and I could send another byte out to make it happen again.
We used paperclips on a couple of machines as an emergency hack - but later versions used a 'dongle' plug that went into the RS232 port with a wire soldered across those two pins)...this plug was named the HPE..."Hardware Paperclip Emulator".
www.sjbaker.org
Once got stranded out in back country (I am a DirectTv installer) with a dead battery and no jumper cables. Used an 18 volt DeWalt battery from my drill and two pieces of copper ground wire to jumpstart van. Lots of sparks but it worked.
Back in the day friends were into doing Lazertag with the original retail guns and detectors and they came to me to see what I could do for them. I reverse-engineered a gun, scoped the output to the IR LED in the muzzle and discovered it was a simple short burst of 1kHz, nothing complicated for the target detectors to register.
By the time I had finished they had a couple of hand grenades (push a button, toss it at the Other Guys, three seconds later it fired a burst of 1kHz through a bunch of small IR LEDs peeking through holes of the plastic casing made from laundry detergent globes) and a "knife" (push the handle down against the Other Guy's body close to their target, another short burst of IR from LEDs in the handle shielded from the holder). The best item though was the "bomb on a stick", an omnidirectional radiator on a short pole, just push it round a corner and fire it off. That one emitted for as long as the switch was held down and it had a LOT of IR LEDs. One-shot room clearance FTW.
Back in the days of punch cards, I was working as an intern. There were several large trays of cards that were sitting untouched for a long time. I was told that two sets of unrelated data had accidentally been collated together into more-less-random order and no-one had come up with a way to separate them other than manually. As there were perhaps 20,000 cards the other operators were doing their best to ignore them.
While the others were at lunch, I looked them over. The most obvious difference was color, one set buff, and the other set blue. Then I noticed that one set had a corner-cut on the left and the other set on the right. Poking into the card sorter, I found I could loosen one of the metal hole sensing brushes and cock it to one side to sense the cut corner. In just a few minutes I had the two sets cleanly separated and back into separate trays.
When the others returned, I pointed to the result. They asked me how I had done this. I told them I had set up the sorter to sort on color and never did tell them the real story.
I bought an old Magnavox tv with built in Pong, but it was missing the controllers. To play games, my brother and I would shove speaker wires into the ports and hold the bare wires with our hands.
By staying very still and very carefully pinching one wire in each hand, tips of fingers touching, we could control the resistance in the range needed to start and control the game. So much as a twitch or turning your head would cause the pong paddle to go off the screen.
Holding that still and staring at the tv, it looked like we were controlling it with our minds.
After a couple days, the TV died. But $18 well spent.
The world is made by those who show up for the job.