[sdiy] Re:Need Some Advice

[Ken Stone]

>This reminds me of something I do which is probably good practice - wear
>safety glasses the first time you power up an untested circuit.
>
>I have fortunately only heard the whistle of IC casing as it flew past my
>ear, never the sound of it hitting my eye...
>
>Colin f

I've opened the lids on a whole board of CMOS once. The thing was powered
from a generator, and the generator over revved. The voltage to the board
must have gone to only 19 or 20 volts, but that was enough. The repaired
board contained a new addition - overvoltage protection.

Mind you, the most fun I had was when my boss told me to reverse the power
to an expensive prototype that a contracted company had built. This (pack of
idiots) company who had convinced my boss to replace the simple z80 system I
had designed with a way to complicated thing full of exotic chips, refused
to put in reverse polarity protection, even after I demanded it. They were
to stubborn/stupid to believe me that this thing was going to be used by
road workers, not engineers. So I reversed the power to it - from the nice
low impedance lead-acid truck battery it was meant to be powered from, and
watched the baby burn. It really freaked out the design company too - after
all it was the prototype, and contained the only chips of that type
available to the country. Now how did they plan to do a production run?

>This reminds me of something I do which is probably good practice - wear
>safety glasses the first time you power up an untested circuit.
>
>I have fortunately only heard the whistle of IC casing as it flew past my
>ear, never the sound of it hitting my eye...
>
>Colin f
_______________________________________________________________________
Ken Stone   sasami at blaze.net.au  
Modular Synth <http://www.blaze.net.au/~sasami/synth/>
Catgirl Paradise <http://www.anime.net/~kens/>
Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>