01-07-2022, 01:03 PM
I think that I can rule out the open secondary winding as 85B has plenty of effect on the signal at the plates of the 6H6; as I stated before, I could easily trim 77, 85B, and 85A for maximum signal at the plates with the oscilloscope. What I was referring to was that the small voltage across the cathodes did not change with 85B. I think my Hallicrafter S40 uses a 6H6, but I think it is a metal one. At least I can test the Philco 6H6G in it. Maybe I will make an adapter the try the metal tube....