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Abused, But Working Hardware Stories?
RPI Geek writes "Everyone's heard the stories about people who, knowingly or unknowingly, abuse their computers. Personally, I've had a faulty power supply literally burn a hole through the motherboard, with the only ill effects being a dead PCI slot and USB ports. I'm curious as to what kind of abuse fellow /.ers have done or seen done to electronics while the hardware still worked afterwards. Soldered a broken keyboard PCB back together so that it worked fine? Taken sticks of RAM out of a running computer to see when it would notice? Overclocked a 386... to 386MHz? I'm interested in hearing any stories about abused-but-working hardware."
Most likely what you heard was an electrolytic capacitor. They are used as filter capacitors for your power supply. Without them you may here some humming, but the amplifier will work fine.
Speakers rated 6V will most likely have 10V capacitors, which will explode in the way you describe when applying 18V AC.
To Terminate, or not to Terminate, that's the question - SCSIROB
I kept my Airport Base Station beneath a planter in my living room. One day I watered the plant and dripped some water on the base station. Fried immediately, the lovely smell of magic blue smoke - or so I thought.
I opened it and noticed the two main capacitors had bulging tops. Turns out the original Airport Base Station had poorly rated capacitors, and they were prone to dying. The bulging top is a clear sign of failure. A website explained which capacitors make appropriate replacements. For the 5 dollars it would cost I figured it was worth a try.
Turned out it was a good gamble. After soldering in the new capacitors the bloody thing worked again.
There are probably a few busted Airport Base Stations floating around out there - and well worth recovering. The older graphite model is the one with the poorly rated capacitors. Even if the base station itself can't be fixed it contains a Lucent wireless PCMCIA card which may be perfectly usable.
-- thinkyhead software and media
That guy is/was an idiot, and you're too if you think ESD is a myth. ESD can cause anything from no effect through intermittent problems to complete failure, depending on your luck mostly. Obviously older hardware with comparably huge transistors stand less of a chance to die from ESD, but even those are not immune. Don't even think about trying something similar with current hardware.
My point-n-shoot camera's viewfinder got dirty. I opened it to clean it out, and touched the capacitor for the flash light (12v). It knocked me unconcious and burned my hand.
Yeah, 12v can bite.
The flash capacitor is about 4kV, not 12V. The whining noise after you fire it is the inverter pumping the cap back up for the next shot. It's also not current-limited, delivering all power it can to the flashtube in a few milliseconds. The TV EHT supply you mention later *is* current limited hence it gives less of a perceived shock even though the voltage is much higher.
I've taken belts from a camera's flash cap before now; they made my arm muscles spasm and throw the camera across the room.
Unfotunately, you assume one very wrong thing...
Your skin has a "break down voltage", much like a diode has. Past a certain voltage, your skin no longer provides much resistance (I don't have the exact values) and so as voltage increases, your "hand to ground" resistance decreases. This causes the current to increase exponentially, not linearly.
So you are absolutely not safe in touching 240V.
Girmann
Nietzsche is dead. --God