workshops

[Doug Tymofichuk]

 	[Rory McDonald]  I got a bunch of electrolytic caps 
> along with some transistors etc on ebay when I bought some 
> chips for Apple equipment.  The caps and transistors are 
> unused old stock, probably from around 1983.  I am 
> wondering if the caps are still useful, or should I avoid 
> them.  They look to be in good shape, but I dont know 
> electrically if it is a good idea to use them.  Anyone?

Electrolytics typically age due to heat. This can be in the 
form of external heat from the environment or heat 
generated internally as a result of current flow in the 
cap. If the caps have been stored at room temp or colder 
and don't show any signs of leakage, then they are probably 
O.K. A quick check with a cap meter would confirm this. If 
they have been salvaged from somewhere, it is hard to know 
how hot they got during use, so their condition will be 
unpredictable. As you say they are unused old stock, they 
should be good.

Hope this helps!
----------------------
Doug Tymofichuk
dougt at cancerboard.ab.ca