12-08-2021, 09:30 PM
The lamp of the Band 4 had the wire going to the switch broken. Easy.
I also look into the shadow meter, and decided all was good inside, so the arm holding the bulb got a bit of adjustment and now it works just fine.
After a while I started getting some raspy distortion that would come and go. I changed driver, a 42; it seems to have become less but once in a while a hint of it would still come.
Then I remembered that the 20-100-130 Ohm divider that creates the biases for the 1st AF and the driver (77 and 42) was in fact 21-170-200 or so, so I paralleled two resistors to make it 21-101-120, close enough to the original.
The radio seems to play clear for awhile but I have to run it for much longer to make sure this does not return, as I cannot quite explain it with the grid bias that is a bit less negative.
I guess it will have to wait after the vacation; I am going in three days.
I also look into the shadow meter, and decided all was good inside, so the arm holding the bulb got a bit of adjustment and now it works just fine.
After a while I started getting some raspy distortion that would come and go. I changed driver, a 42; it seems to have become less but once in a while a hint of it would still come.
Then I remembered that the 20-100-130 Ohm divider that creates the biases for the 1st AF and the driver (77 and 42) was in fact 21-170-200 or so, so I paralleled two resistors to make it 21-101-120, close enough to the original.
The radio seems to play clear for awhile but I have to run it for much longer to make sure this does not return, as I cannot quite explain it with the grid bias that is a bit less negative.
I guess it will have to wait after the vacation; I am going in three days.
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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