[Phlogiston]

Ok, I have some answers.

The freq is 1mhz.

Hum is very dependent on antenna tuning - good tune less/no hum.

I might still have the schematic, or possibly 35Z5 has it.

I think the tubes are 12V versions - using a 6V was the reason for the bulb/resistor.

Here is my post from that other site:

Well I took out the light bulb ( I kind of miss it) and swapped in the 12 volt tube in place of the 6CS6. Then I swapped out L2 for the 680 uh coil. By the way, I am using the 1000kH x1. The unit tunes to a 10 foot ant now with better range. although what I had before was fine, now you can hear it outside on the truck's radio. Adjusting the VC is easier with peaks not as sharp.

Russ