Zenith 6S254 Intermitten Reception
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>>> It does not play at first power up of the day most times.
So you have to turn it on several times for it to play?
Have you looked at the volume control?
(I am not blaming the power switch as you said the voltages are OK when stopping playing)
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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When you have the problem the set goes quiet and the AVC drops to minimum. That tells me there's no, or very little, signal from the antenna.
When the ground is disconnected from the antenna does the problem occur? Maybe there's a strange ground loop. Usually a ground loop will result in interference or oscillation.
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Volume control seems OK and I have sprayed it with Deoxit F5.
The AVC never varies much whether the reception is good or bad.
I will play the radio with ground disconnected and see how long it lasts.
Earlier this morning when I turned it on it was on the strong station and reception was bad. I turned up the volume to almost max and I could here the station with much noise. Currently the ground is disconnected tuned to strongest station in the area playing as expected with some noise. AVC voltage is -2.3. Off station AVC is -2.5 opposite what I would expect.
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With a strong station I expect to see -5 to -8 volts of AVC.
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That is what I thought. So does that give us a clue?
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Where are you measuring your AVC, and relative to what?
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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On the 6H6 tube pin 8. Pin 4 and 8 are tied together. Positive probe on pin 8 negative probe on ground.
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Is the gimmick made with stranded or single strand wire? Might want to replace it with a 5pf cap.
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Stranded wire. Where do I connect the cap. I assume osc section to ant section of tuning cap?
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The gimmick should have two wires connected. The cap leads go where the gimmick wires are soldered in.
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What you are measuring is mostly voltage created by the Candohm divider between the 27 Ohm and 128 Ohm sections.
And NOT the AVC.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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When I first got the radio the gimmick was connected to the osc section and wrapped around the wire going from ant section to the 6A8 grid. Only one side of gimmick was connected. So not sure how to wire 5pf cap.
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Where do I measure the AVC?
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I think the filtered AVC is C12/R5 connection. Which will be the same voltage as on the Grid of 6A8. (G4, the Grid cap)
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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Ok. I get a decent swing of AVC on the 6A8 grid.
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