On Sat, 18 Dec 2010, 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.

But what are the pots doing? Is this a space saving thing, or is there
some concrete reason why the pots are ganged? Even if they "need" to be
ganged, the circuit will define why, and we don't know what the circuit
is.

Michael VE2BVW