Motorola B12WA recap and mods

[Reece]

Nice looking for a garbage-picked radio!

[wa2ise]

Oh, forgot to mention, first time in a very long time I had a bad ceramic cap. Became shorted. It was a bypass on the heater string. It was throwing off the current thru the heaters.

[dieseljeep]

I see, the set uses a strange type 2nd AM IF circuit. It looks like a single tuned coil for each band.
BTW, what is the true function of network E2? I'm repairing a 6 tube Motorola clock radio, that has a bad 2nd IF transformer. Silver mica disease. This IF has that network built into the base and has 6 terminals. I'm just going to install a standard output IF and wire in the 2, 150pf caps externally.
I can't see why it wouldn't work as well.

[dieseljeep]

Originally Posted by dieseljeep

I see, the set uses a strange type 2nd AM IF circuit. It looks like a single tuned coil for each band.
BTW, what is the true function of network E2? I'm repairing a 6 tube Motorola clock radio, that has a bad 2nd IF transformer. Silver mica disease. This IF has that network built into the base and has 6 terminals. I'm just going to install a standard output IF and wire in the 2, 150pf caps externally.
I can't see why it wouldn't work as well.

Both IF transformers had the silver mica disease. I tried my hand at repairing the transformers, as they're rather hard to get. They're EIA 119 sourced and have the brass rivet holding the base together. I think, I've succeeded.