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Okay Don, I've got fresh numbers for voltages on the 6AQ5 audio output - all with a VTVM. Sam's calls for -3.8 VDC on the control grid, pin 1/7, and I get 135 whether to ground or to the cathode, pin 2. For the screen grid Sam's calls for 165VDC measured to pin 2 and I measure 150 (Rider's calls for 290 to ground and I get 285). Sam's calls for 145 on the plate to cathode and I get 140 (Rider's 280 to ground and I get 275).
Specified line voltage is 117 and that's what I measure.
B+ voltages measured against Sams are 330/330, 325/312 and 310/270 - with the focus control at mid position.
The focus coil should be 170 and I read 180 ohms on the original and 184 on the "sub" from another Philco. That sub had just a hair better focus - very subjective (and still full CW).
The focus pot ranges from 0 to 500 ohms - on the money.
You asked about the stacking resistor. I presume that would be the Sam's R78 sand type listed as a "decoupling-wirewound." I subbed a new 5K sand and there was no change in focus.
As to measuring the total current drain - I don't have an ammeter that will handle AC. Perhaps I could measure somewhere after rectification?
I mention again - since we're "focusing" on the audio amp - that my audio is just barely enough - with the volume control fully advanced there is no "extra" volume available.
Also, I notice that according to my tube manual, the 6V6 does not use pin 6. Yet, Rider's shows the pin 6 connected to the 135V supply. Sam's shows two possible arrangements - one connects pin 6 to the 6AQ6 cathode and the other connects pin 6 through a resistor to the 310V supply. My 6V6 socket has a pin 6 that's clean as a whistle - looks like it's never been used. Could there have been a later factory mod?
When I pulled the 6AQ5 it killed the sound but a somewhat "faded" pix remained.
Roger
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