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THE AM BULLETIN BOARD => Technical Forum => Topic started by: W9ZSL on April 14, 2016, 06:15:00 PM



Title: B&W B-TEL Restoration/Wiring (GOT A DIAGRAM)
Post by: W9ZSL on April 14, 2016, 06:15:00 PM
I scored a B&W BTEL 3816 10-80 Turret in relatively decent shape for a fair price.  I'm planning on using it for the input of that mythical transmitter / amp combo (single 813 until I change my mind AGAIN).  Beats building one.  The mounts for all 5 coils are shot.  The plastic and glue has deteriorated and become brittle.  As can be seen in the pix, the supports were inside the coils.  The rear plate was bent which displaced the coils.  That should be an easy fix.  What do you recommend for the supports?  The original plastic is 1/16".  I can probably go with 1/8" Lexan with epoxy as a binder.  The screws might be a problem as for replacement.  You can see the damage in the pix which shows the 3 solder terminals.

My second question is wiring.  There are three terminals which have been soldered to the single ceramic switch wafer (1) and the two phenolic (1 each). I assume there is a common ground for both the resonant coils and end-load coils plus  input/output terminals which I assume can be interchanged with the end-loaded used as inputs and the tuned coils paralleled with a variable cap for the grid?

I have yet to hook a meter on the animal to do some checks, but as shown in the pix, it looks like there are only 3 terminals for hook up.  The ceramic wafer has a wire that was cut and is on the upper left.
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