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Help with schematic interpretation
Radioroslyn
Phorum Expert
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Posts: 7,283
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
#4

09-07-2022, 07:29 PM
No. Unground the ct of the 2.5v filament winding. Reconnect the cap and the 1.6k resistor as per the original diagram. The end of the resistor that was not connected ground it. This restores the filament bias network. As it was with the tap grounded there was very little - voltage being developed on the control grid. This causes the tube to draw an excessive amount of plate current.
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry
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RE: Help with schematic interpretation - by Radioroslyn - 09-07-2022, 07:29 PM



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  1. The PHILCO Phorum
  2. Various and Sundry Categories
  3. Other Radios (Non-Philco)