12-11-2010, 04:41 PM
Hmmmm Doesn't sound good. I would disconnect the shadow graph and check the resistance of the coil. It may be open (not good) You could add a jumper across the the graph and see if that helps the performance. Check #47 for shorts and the #76 tube for shorts.
Sparking form the bandswitch is bad! You will need to take a close look at it and find out whats arcing. Clean well make sure that there aren't any carbon traces. If you don't you can burn up the phenolic part of the switch then the terminals will come apart.Sometimes you can use a bit of epoxy to repair the wafer. Double check any parts of the switch that has B+ on it. Those would be the ones connected to the plate circuits of the RF amp and the LO.
Good luck
Terry
Sparking form the bandswitch is bad! You will need to take a close look at it and find out whats arcing. Clean well make sure that there aren't any carbon traces. If you don't you can burn up the phenolic part of the switch then the terminals will come apart.Sometimes you can use a bit of epoxy to repair the wafer. Double check any parts of the switch that has B+ on it. Those would be the ones connected to the plate circuits of the RF amp and the LO.
Good luck
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 it!
Terry
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