On 12/18/2010 4:42 PM, Mahoidar wrote:
I am looking for parts to build a portable tube transmitter-receiver
project from an artcle that appeared in the September 1950's QST.
It utilises a dual potentiometer, one gang is 2M ohm, the other is 5K ohms.
The parts list gives the 2M as "RC M13-139" and the 5K as "IRC PQ 11-114".
Do these numbers mean anything to anyone, and if so, please can you explain?
Any assistance will be greatly appreciated.



Hi,

You can use two pots - one is for the rcvr audio gain,
and the other is for IF gain, as explained on page 19 of the article.
Use an audio taper pot for the 2M pot section,
and a linear pot for the 5K.