[zboltman]

Hi John,
Yes, I read about that 0.5meg thru your notes, (Thank You).
So, I opened up the pot, cleaned it, lubed it and re-measured it.
(Oh and by the way, the inside cover of the pot had a date stamp on it of Nov 6th, 1931!)
It is now measuring 2.8 meg ohm across the outer terms. 
From the center term, it does a clean linear measurement from side to side.
Yet, upon re-installing it; I still get noise when I adjust it.
(I put the old original tube in and it still didn't function, so I put the new, (24), replacement tube.)
The radio is still not receiving. 
I know I still have to do a lot of work to do about replacing individual components
I bought 2, a 24 and a 224 together.
The 24 lights up, but not the 224. :-(
Here are the notes from the seller:
One is a National Union NY-224 type 24A vacuum tube, and the other is a Philco type 24.
These tubes tested GOOD on a reliable Hickok Model 800A tube tester (a dynamic mutual conductance tester).     ... and NO shorts or gas detected.
They both had readings of 600 micromhos.  These tube are right at the minimum, but should still be usable. 
Ref:  Minimum readings should be 600 micromhos (60%) and new tubes should test at 1000 or more micromhos. 

Here is my question, based on the reference to the schematic, should I replace the original with a 500K ohm pot?