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Ask Slashdot: 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?
The paper-clip CD extractor. I keep one in my desk at all times.
Put it all together for near-real-time track of how much it costs to keep my basement at a given humidity.
The Raspberry Pi caches readings in a local database in case it can't connect to the web, then stores in a database on my web server. The database ingestion also keeps a 2-hour running average to smooth things out a bit.
When I set it up, I thought it wasn't working right - I saw sawtooth-like patterns in the humidity data. Turned out, it was working perfectly: the resolution of the humidity sensor was good enough that I could watch the humidity in the room rise until the dehumidifier kicked on!
A company I worked at used to have an annual mini golf hole contest. I hollowed out a computer and ran the ball through it in some 1/2 pvc pipes with the cd tray popping in and out (a batch file from a boot floppy) as a moving obstacle.
The HP28C had an infrared output, e.g. For printers, but no input. a friend of mine published a book explaining how to connect an IR diode to trigger some unconnected keyboard lines in the calculator. That made it possible to upload programs to the calculator faster. Of course you also needed the matching hack on a PC to send programs. The 48 had IR in both directions.
-- Did you try Tao3D? http://tao3d.sourceforge.net
Back in the early 90s my dad repurposed an old Tandy laptop to effectively act as a scheduled wall timer for a "VCR for tape decks". He used the parallel port to send current to a few signaling contacts on a cassette recorder in order to record Car Talk and a few other radio programs he liked. A patent was considered, but podcasts rapidly became a thing a year or two after he had it working nicely. Not a bit of that statement that fails to make me feel a bit old.
Back in the '80s, I was in Highschool. We had Commodore PETs that we used for our computer class, and being a geek/nerd, I was regularly abused by the cool kids. Well...one year, I got back at them. They were taking the computer class I was in. Commodore gear was "smart" - each peripheral had a small CPU and could be programmed. So...I hacked the code for the floppy disk drives (in assembler) and when it saw a file coming across it would look at the user. If it was me or someone I chose, it would work normally. However, for those unlucky few individuals whom I had decided to take revenge, it appeared to be working, but actually it was formatting the floppy disk. Those bullies lost their year end projects and all their work. I have to admit that I felt no guilt about this incident.
Can't you just read the answer off your mom's utility bill?
I come here for the love
I was deployed to Iraq, and we had to download a very large file. Unfortunately, we were working on laptops that would lock the screen after 15 minutes, and then the laptop would loose connection. Considering that the file was going to take 8-10 hours to download, this was not acceptable. I found an oscillating pedestal fan, and I duct-taped a yardstick between the fan and a mouse connected to the laptop. Since the laptop would not lock due to the mouse movement, all I had to do is to place a few books to limit the moment area; the next morning the file was downloaded. I realize this might not be the hack for which you were looking, but since it involved duct-tape I thought it would count.
I'm a professional hacker, you insensitive clod!
I checked out a book on tape at the library called "What would MacGyver do" about true stories.
After listening to several real stories I realized that just myself and my immediate family could
fill an entire book full of better "hacks" that were listed in that book. Most of them I had never
considered "note worthy" until finding a entire book with many other less note-worthy stories in it.
The hack I'm probably most proud of is rather simple. My work was needing a watchdog timer
to reboot locked servers and most of the off the shelf solutions were several hundred dollars
so instead I created a simple program on an arduino that connected to the power button and
the usb port so it could "press" the power button if there was a hard lock. It has been deployed
with several hundred servers at this point and at a fraction of the cost of most other solutions.
During the age of the "CB" radio craze, I made an antenna out of a fiberglass whip flag that was on my bicycle, mounted the radio on a bracket on the handlebars, used a magnetic mount for the microphone. Rigged up a generator out of one of those bicycle light thingys, to kind of trickle charge the 2 6 volt lantern batteries mounted where the water bottle went. Worked pretty good. Use to get truckers going back & forth across the state on U.S. highway 50 would call me on the radio wanting to see it if I was on the air. What the heck...wasn't much to do in a small town, if you were 14, in the mid 70's.
We had a server at a co-lo that was locking up on a regular basis. It had a phone line that it used on an infrequent basis with a modem to send faxes. When it would lock up, usually at 4 am, I would have to drive 45 minutes to the co-lo in order to press the reset button. I took an old 1200 baud modem, and cut the traces on the PC board where the off-hook relay connected to the analog phone circuitry, and instead brought those relay contacts out to a set of wires. I hooked those wires into the reset switch on the server, put the modem on the same phone line as the outgoing fax line, and set the modem to auto-answer after 20 rings. There were never any legitmate incoming phone calls on that line, and any random wrong numbers would give up after 4-5 rings. When the server did lock up, I would just dial the number of the outgoing fax line and let it ring 20 times. The modem would "answer" - but the relay would actually "press" the reset button on the server instead, saving me a 45 minute drive.
At one time I got a broken MagSafe power supply, the ones that Apple ships with their laptops. Since I was curious how these switched-mode power supplies work, I cracked it open and somehow shorted the big capacitor. These temporarily store up to 400 volts but it wasn't that much left. I still got quite a zap, though :-)
Anyway, I got a big crate of broken ones from a local Apple dealer in town. I found out that they usually didn't work because the wire would break close to the adapter. eBay sold replacement cables and I started fixing the power supplies. Cracking them open, replacing the cord, testing them, glueing them shut as neat as possible, then selling them for 25 bucks.
It was fun but with a kid on the way, I had no room for a separate table for my soldering iron, electronics stuff etc. and I stopped doing it. Cleaning up every time you want to do something small isn't fun.
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I was missing the hardware to mount a 5 Mb hard drive (yes, 5 Mb) in my XT. Didn't want it sitting directly on the case (cable length, vibration, possible short, etc), but really wanted that upgrade. My French-English dictionary was sitting nearby, so it became the support "bracket".
My mom used that computer many years for checking email (she did upgrade to 2400 baud), but one day it needed a repair. She said the guy was a bit surprised to find a library in a PC.
The world is made by those who show up for the job.
nice. I used a pager connected to a relay across the reset switch. Dirty but it worked.
Political debates have me rolling my eyes so much I think I got optical whiplash. I should sue. - Foamy The Squirrel
I get a lot of crap at yard sales, thrift stores, etc. Eventually the stuff makes its way into projects. Got some of those NHT transducers out of some toy cardboard guitar amplifiers. Used one of them to make a lunchbox into a speaker, it sounds a little tinny... Got a LCD backup mirror with a broken mirror for $10, nice source of a backup camera (with range marks) and a 4.3" LCD. $10 later and I've got a touch panel to go with it, I plan to attach them to my R-Pi soon.
Outside I've made a table for my (yard-sale acquired) lathe out of pallets and I made a 4x8 table saw by making a wooden frame for a portable jobsite table saw I got for ten bucks missing the extending fences and whatnot but with the pusher.
I don't depend on this stuff for livelihood, it's just a hobby, but you can live better on the trash in this country than you can on normal wages in some others. There's just valuable shit going to hell everywhere. If you could line up end-to-end all the cars that people would have liked to fix up which have been parked in people's yard and just rusted away, they'd probably reach across the country.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Old HP GPIB-based XY plotter with laser diode in place of pen, does a nice job of cutting gaskets for steam engines.
Broken 8 track player in ginormous am/fm/turntable cabinet, replaced with beaglebone, so when I hit the next track button it plays a 'clunk' sound and then fires up a random streaming internet radio station. (That one made hackaday.)
A nearby company went out of business and sold all their stuff and I scored an electronic balance with an RS232 output. Some arduino code later, and I now have a fuel injector flow tester: force known-pressure fuel in for a known amount of time and measure how much actually comes out, tare, repeat. It's neat to be able to characterize just how narrow a PWM signal the injector can register and react to.
My current work project is even a hack: I'm repurposing an abandoned semiconductor automated test system into an evaluation board characterization system. The test guys don't want it because it's too slow and limited, but I'm all "whoah, 192 arbitrary waveform generators? Let me at it."
Nostalgia's not what it used to be.
Yes, half of a clothespin (sans spring), saved having to order a hard drive mounting assy for my laptop's second drive port, perfect size to keep it snug. That'd probably be my most unusual, all the others were relatively mundane.
Oh wait, as a kid, not allowed to read after bedtime, I ran a wire from a train transformer to the room door frame wrapped around a metal tack, a matching thumbtack on the top of the door with wire going to a spare 12v auto parking light bulb and back to the transformer completed the circuit. I got away with reading at night for years just needing to hide just the book, not flashlight too, if Mom checked on me from seeing light spilling out under the door.
But I don't consider turning my door into a knife switch unusual.
The day she pounded on my ground floor window from outside shouting "go to sleep" did make me jump and lay awake a long time though!
YOU'RE NOT MY REAL FATHER!!!
Oh, god, space technology is full of brilliant hacks. For example, New Horizons' radio. It has two amps connected to one dish, designed as a primary and a backup. But while it was en route, an engineer hit upon an idea to have them both transmit at the same time through the same dish, doubling the bandwidth. Normally that wouldn't make sense, except that the amplifiers have signals with different polarization, and these can be separated back out on Earth.
Great, except for one problem. The second radio was designed as a backup, they weren't planned for simultaneous operation - so there's not enough power to run them both and everything else at the same time. There's barely enough power to run just the radios - and I mean, it's not like you can just shut off the flight computer to free up more power. Well... actually, that's exactly what they do. When have a ton of data accumulated that they want to get to Earth and no critical science to do, they spin the craft up like a bullet to keep it stable and the dish pointing at Earth. Then they shut down the whole guidance and control system and pretty much everything else on the craft not essential for reading and transmitting data. It stays in this mode for days for a week or two, until all of the onboard data is transmitted, then they spin it back down so that they can do things like take pictures once again.
"Who the **** put an emergency exit in the interrogation room?!" -- Police chief, "Jesus Christ Supercop"
You made a time machine and still didn't get first post? Hmm.
Cool! My solution in the 90's to that problem was to find some ip power switches so I could power cycle the devices remotely. It wouldn't be an acceptable solution today.
That would have probably worked except in this case the servers are what are providing the
connection so if they go down so does the connection. Telemetry operations where you are
operating a remote server over a single pipe and have no easy way to repair it or even reboot
it makes for quite a few creative solutions to try to not have to send a technician to a remote
location.
Would have been terrible if a telemarketer ever got that number.
This. It's really a cleaner even though we've all used it like a lube.
funnily enough, that never became an issue.
Can't think why but they seem to have managed to avoid the pager block when they were all the rage, preferring instead to harass landlines. Of course, when cellphones really took off in the fashion consumer market, pagers died a death. I don't even know if they got the "7" when the DEXes were updated.
Political debates have me rolling my eyes so much I think I got optical whiplash. I should sue. - Foamy The Squirrel
Years ago the local cable internet provider had a rather low cap (10GB/day) after which your connection would drop to some ridiculous speed. Fortunately their implementation was rather incompetent, tied to IP addresses rather than modems. If you just rebooted the modem to get a new IP address via DHCP it reset the cap for that day. Some people but their modems on timers designed to turn appliances on/off at set times, so that they got a new IP address every hour and avoided the cap.
They eventually figured that out and changed the system to use the modem's MAC address. That could be bypassed by changing the modem's MAC address to one used by another subscriber. You could gather valid addresses by simply watching the traffic on your local network segment. Some people had JTAG connectors permanently attached to their modems so they could cycle MAC addresses regularly.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
I'm not trying to troll, but am genuinely curious as to what you're doing if you've got several hundred servers running that are at enough of a risk of locking up hard enough that they need a physical power cycle to reset them?
They are linux boxes and they actually rarely hard locked. The problem is that they are all
in remote locations several states away with no way to reboot them if something does go wrong
so even if they only freeze once a year it is alot cheaper to put a watchdog timer in them
than to pay someone to drive there to press the power button.