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previous: anonymous Hey Mark:Just a sma... -- 3/28/2000 1:24 PM View Thread

Re: How to identify "good" Ge transistors?

3/28/2000 4:36 PM
Mark Hammer
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Re: How to identify "good" Ge transistors?
I don't get a "jump" in readings, merely something that keeps going up and up. The fluctuation-then-stabilization you describe is VERY familiar. Glad to hear it is a normal part of their behaviour. Indeed, this probably answers my original concerns. I was fairly sure that the unit which started out at an hfe of 115 and ended up at 180 before I took it out of the test socket was probably a bad device, but initially, I wasn't sure if the one which hovered from 112 to 118 and settled at 117 was exhibitting something expected of a normal or bad device. I suspect the heat from my fingers, while trying seat the device right probably exacerbated the phenomenon, further blurring the boundary between good and bad.  
 
Using a breadboard for the test socket is sound practice and a great idea. I think I'll start doing it. Thanks for setting me straight and allaying my fears. I suspect I have a MUCH bigger assortment of usable GE devices now than I thought.

 
Replies:
Mike I. Probably the easiest way to test th... -- 3/28/2000 5:14 PM
J Epstein I have had JFET's do this heat-vari... -- 4/10/2000 3:04 PM