Identifying tempcos

Christian Hofmann chris at
Tue Nov 9 17:39:54 CET 1999

On Tue, 9 Nov 1999 08:39:56 -0700 (Mountain Standard Time)
Doug Tymofichuk <dougt at> wrote:

> Hello everyone,
> With all this talk about tempcos, I am wondering if I might 
> encounter some when salvaging equipment. As I have never 
> actually seen one, I wonder if there is any way to 
> physically identify them. Do they have any unique markings 
> or anything to show what they are? Or do they just look 
> like any other resistor?

The only ones I can think of having seen are in the Jupiter 8. They are
tiny square parts, about the size of a match head, with 2 flat connector
pins. IIRC nothing there's written on them. The manual refers to them as
posistors, which appears to be what we call tempcos.

To identify tempcos, look out for anything suspicous glued on top of
something looking like a (double) transistor, or on a DIL 14 transistor
array chip as in the JP8.


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