11-01-2010, 09:14 PM
Well lemme scratch my head a bit hummmm
Check #26 grid bias seems a bit low on the 42 tube.
Check #19 screen voltage seems to low on the det tube. That's a little tricky to measure as they don't tell if the det is oscillating or not. That will affect the readings.
Check #6 That will affect the control grid voltage on the mixer.
How much voltage do you have across #36?
Have you tried the align the if trimmer (#17) to 450kc? (frequency not regeneration)
Check #7 and #12 by making sure there not short to the chaiss and loosen the adj nut and retighten it to about where it was set before.
Check the the two windings on the osc coil for resistance should very low a few ohms if good
I think I would start at the speaker side of things and work towards the ant. Get bias up a bit on the 42 tube and align the 450kc if and get the if to regenerate. (I'll bet the #19,20,22,and 11 are bad)
Terry
Check #26 grid bias seems a bit low on the 42 tube.
Check #19 screen voltage seems to low on the det tube. That's a little tricky to measure as they don't tell if the det is oscillating or not. That will affect the readings.
Check #6 That will affect the control grid voltage on the mixer.
How much voltage do you have across #36?
Have you tried the align the if trimmer (#17) to 450kc? (frequency not regeneration)
Check #7 and #12 by making sure there not short to the chaiss and loosen the adj nut and retighten it to about where it was set before.
Check the the two windings on the osc coil for resistance should very low a few ohms if good
I think I would start at the speaker side of things and work towards the ant. Get bias up a bit on the 42 tube and align the 450kc if and get the if to regenerate. (I'll bet the #19,20,22,and 11 are bad)
Terry
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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