Society of Robots - Robot Forum

General Misc => Misc => Topic started by: blackbeard on December 19, 2009, 12:14:40 PM

Title: your electronics blunders
Post by: blackbeard on December 19, 2009, 12:14:40 PM
what silly things have you done during electronics ventures? personally my most recent thing was working 8 hrs + on a mini robot wearable as a shield for the arduino. after thinking it was shorting out for a few hours and modifying it to the point of no return i discovered it was actually a resistor pressing the reset button for the hole time :P
Title: Re: your electronics blunders
Post by: z.s.tar.gz on December 19, 2009, 01:35:49 PM
Didn't connect to ground.
Title: Re: your electronics blunders
Post by: little-c on December 20, 2009, 03:30:57 PM
made an uber cool 6V battery from a lead battery, all happy with short protection, charging curcitry ect.

fuse holder broke off mount. ah sod it, doesn't matter.

smoke, flames and half ton of fairly leathal polution latter... turns out it shorted on the fuse terminal on the battery side of the wire I know this cause it soldered itself to it. and burnt the wire in half...

-----(fuse)l----battery terminal
             l
-------------l----other battery terminal

humm. it probably did matter.....
Title: Re: your electronics blunders
Post by: SmAsH on December 20, 2009, 03:45:38 PM
Didn't realize the scissors i was using to short a 400v cap had metal handles...
I've always treated my pc insides better since.
Title: Re: your electronics blunders
Post by: frank26080115 on December 21, 2009, 09:04:27 PM
the most painful was an accident while taking apart a disposable camera once, you can guess what happened
Title: Re: your electronics blunders
Post by: madsci1016 on December 21, 2009, 09:22:09 PM
Solder burns and exacto knifes cuts on fingers (to the bone) .

Shorted (by accident ) a 1 farad (!) Cap at 12 V. That was scary.

Built a Tesla coil that failed in a 5 second glorious light show.

Got caught running a 12KV transformer for a Jacob's ladder in my dorm room. They had to add a new rule to the contract for that one.

Never really mis-wired and destroyed electronics (that i can remember), and knock on wood i keep that trend up.

The first memory i have is being a baby and sticking a knife into an electrical outlet, burning my hand from the shock. I thought i made it up in a dream until my parents told me it really happened.
Title: Re: your electronics blunders
Post by: guncha on December 23, 2009, 10:11:27 AM
Forgot that a 60$ bluetooth adapter from Sparkfun runs on 3.3V not 5V.
Title: Re: your electronics blunders
Post by: Joker94 on December 23, 2009, 06:01:19 PM
one thing i really remeber is when my voltage regulato fried. It was amazing and it looked great, blue and purple flames.

another thing was when i intentiolly blew up a capacitor. it was loud but awsome.

and not to mention the obvious soldering iron burn.
Title: Re: your electronics blunders
Post by: Pratheek on December 24, 2009, 09:31:24 AM
Once I connected a Li-ion battery pack to the charger incorrectly and the next moment the the charger was in fumes(literally). After a few seconds, even before I could think of what was happening, I could see the charger's IC turn red!
Blew up a 30$ charger that day. Surprisingly nothing happened to the battery.

Another time, my brother had borrowed my soldering iron, before returning it for some reason he had removed the tip and washed it. While I was using the soldering iron and brought the soldering wire to the tip, I got a bad shock in the hand!
Later I figured out that the water after washing had not dried completely and allowed the current from the heating element pass to the tip then to the soldering wire and to my hand holding it!
Title: Re: your electronics blunders
Post by: TrickyNekro on December 24, 2009, 04:21:07 PM
Well, I was repairing a sat receiver power supply, and I was trying out different values for that big 400V capacitor,
It seems, for some values resonance isn't happening at all allowing the capacitor to hold charge...
Hell I had that capacitor discharging through my finger for about 5 sec before I would realize why I was having this strange feeling at it...
It was a nasty shock... But a little bit entertaining I would say!!! :D
Nothing else serious enough to mention....
Title: Re: your electronics blunders
Post by: jka on December 27, 2009, 06:27:00 AM
Burned off two 3.3V regulators, adding all sorts of short circuit protection and cooling after the first. After the second, I reread the datasheet and found out that max input voltage was 6V. I was feeding it 9V...
Title: Re: your electronics blunders
Post by: arixrobotics on December 27, 2009, 10:12:08 PM
I once connected an LED (without any resistor) directly to a variable AC power supply originally used for an electric train set. I foolishly thought I would be able to see the LED blink as the supply was AC  :P  (this was way before I understand basic electronics).

It turned out that the AC voltage was really big that the LED lit up brightly for a split second, and then the LED's plastic casing blew up into two pieces  :o

Title: Re: your electronics blunders
Post by: Hawaii00000 on December 28, 2009, 06:24:20 PM
Well I've grabed the wrong end of the soldering iron...more than once, fried a couple things. Never actually got zapped when I was pulling apart a disposable camera, but I almost had a heart attack when I shorted it out.
Title: Re: your electronics blunders
Post by: Hertz32 on January 06, 2010, 03:27:42 PM
burnt myself on a soldering iron then dropped it on a fantastic new board which melted as a result
Title: Re: your electronics blunders
Post by: ComputerPsi on January 12, 2010, 10:16:32 AM
* Accidently got shocked by the capacitor of a disposable camera multiple times.

* Got shocked by the main electric line when trying to repair the ground. (Somebody decided to turn the electricity back on. :()

* Plugged in a coil of wire into the outlet. The coil (some wire wrapped around a plastic bottle) caught on fire.

* Destroyed about 20 transistors when trying to figure out how to make an amplifier more powerful. (At low power, they die with a small click. At high power, there's a blast and a piece of plastic flies off.

* Destroyed a few powerful (30V >8000uF) capacitors by shorting them too many times.

* Hooked up a weird video port to parallel port converter to my old 486 computer. Smoke started coming out in seconds.

* When I was about 10, we had an old computer that had an "On/Off" switch. At some point, the computer happened to be on and open (the case was removed). There was a harddrive lying around and I wanted to see what will happen if I connect it to the computer while the computer is turned on.
The computer turned off... While the switch was still on "On"... :(

Yep, that's my story. :D
Title: Re: your electronics blunders
Post by: z.s.tar.gz on January 12, 2010, 04:55:12 PM
One time I had a power supply like that where you didn't need a motherboard to turn it on,  so I took a cd drive and hooked it up to see if I could listen to music on it.
Anyways, I was holding the exposed switch in my hand, and didn't check to make sure ground wasn't touching other pins. Big flash and pop. PSU didn't work anymore. Palm was all black but not burnt.