[AMRadio] DRAKE L-4 Amp

John Coleman ARS WA5BXO wa5bxo2005 at pctechref.com
Fri Jun 16 21:57:52 EDT 2006

Regarding the need for the 100K pot:

Is The Pot Open?
Is The Switch bad?

I may have some thing that will work.  

Is the pot a linear resistance movement or logarithmic.  My guess is that it
is linear but the best way to tell is to set the pot at the half way point
between extremes and then measure the resistance from the wiper to one end.
If it is approximately 50K ohms, then it is linear.  Even if one end is open
the other end would still measure about 50K ohms.  On the other hand, if it
measures around 80 or 90K ohms from one side to wiper, or if it measures
around 10 to 20K ohms from one side then it is a logarithmic.  I think I
have some 100K pots but will need to check them and see if one has a switch.

What are the physical dimensions?

John, WA5BXO

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