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Old February 25th 05, 12:47 AM
Scott Dorsey
 
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Antonio Vernucci wrote:
I found the table. The original potentiometer behaves as follows:

Reading on scale Ohm
10 55
20 175
30 360
40 825
50 1200
60 1700
70 2190
80 2900


Okay, if you used a standard "audio taper" 3K pot, you would get:

Full left 0
25% 189
50% 450
75% 1500
100% 3000

This looks like a slightly different taper, but probably close enough
that you could get away with it by slightly altering the markings.

Thanks for the suggestion to use a standard potentiometer that =
approximately has the same behaviour and to paste a paper scale to =
compensate for the difference. However, I will have to verify two =
things:

- whether potentiometers having a similar behaviour can really be easily =
found


You can get audio taper pots easily, which have a standard log scale.
Getting antilog pots is harder.

- how much power the original potentiometer was supposed to dissipate. =
It may not be easier at all to find high-power carbon potentiometers=20


Now THAT may be the rub. BUT you can still get audio-taper wirewound
pots for speaker level applications. They're getting harder and harder
to find, though.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."