[Hammarlund] Bias supply zorching the audio driver transformer

[Al Santangelo]

Hi Todd,

Great to meet up with you here OM. Hope to hear/work you soon on 75 or
40m for sure. The group is still going strong.

I know it was mentioned to be careful about the bias supply and
damaging the audio driver transformer in the Super Pros.

I was just looking at the schematic for the SP-400X and I see that the
schematic shows the use of cathode bias on the PP 6F6s. ie. the centre
tap of the secondary of the driver transformer is grounded.
I don"t the SP-210 schematic here, so I'm thinking that this is one
other difference between the 400 and the earlier SPs?

Al Santangelo