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trouble found
Thanks for all the help and the schematic sources and the voltage chart. TROUBLE!! The trimmer on the rf section of the variable was partially shorted. On this set the rf amp is only used on the broadcast variable band. I was making resistance checks from ant to grid of rf amp trying to find out if a switch contact or coil was bad and found a short to ground and isolated that as the variable rf section trimmer.
The75mm cap in the grid of the rf amp isolated it from the short and that was why I could touch the rf amp grid or plate or the converter plate and get more signal. Very unusual to find that the rf amp was only used on broadcast. Set still has lots of noise but I will try another location as computer cables and electronic phone systems may be causing that.
Thanks again,
Chuck Azar
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