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zenith 9s-367 question
#1

Hello fella's,
Have a question on a zenith 9s367 chassis that I brought home yesterday.
Upon looking it over, I noticed a .05 cap that was hanging by one end.
It is attached to pin 2 of the 6J5 detector tube and a 3 terminal strip above and to the left of the tube.
I am not seeing this cap on the schematic.
I see a C4 .0001mfd cap on the schematic.
Is there a reason that this disconnected cap was installed there?
It is not a zenith cap, so it is not original.
Was there an upgrade?
Otherwise looks like very minimal work has been done to this chassis.
murf
#2

The schematic shows pin 2 to be connected to the chassis. Was probably used as a bypass cap for something. Would just leave it out and see if it devolves any problematic issues after service.

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
#3

  • Thanks Terry,
  • Main issue i am seeing is it is not really motor boating , but more of a motor beating noise.
    seems to vary with volume. No reception, just noise.Murf
#4

Will leave the cap out as suggested, but the radio is just putting out a lot of noise which varies from a beating noise to a squealing noise if I try to adjust the trimmers.
Seems like it may be an alignment problem?
Have replaced most caps so far and have check the cadohm and a bunch of resistors.
Have the other 12 tube zenith over at a friends for diagnostic and now have another zenith with strange issues.
murf
#5

Well, upon further investigation, i found that someone had removed the bypass cap.
Found a couple extra caps added that were not on the schematic.
Fixed those items and the radio now works great.
Never know what your going to find.
Murf




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