[ARC5] Rheostat Repair

[Mark K3MSB]

Hi All

Thanks for your comments.

Nichrome wire:  Quite a few years ago I replaced the original parasitic
suppressors in a friend's SB-220 linear with an updated set from Rich
Measures using Nichrome wire and silver solder.    I had some solder left
over but looking through the “pile” I can no longer find it.

Welding:   I can check into that but not sure about local availability.

Purchase new pot:   Definite possibility, but the shafts are connected via
a custom coupler that looks to be compression fitted  (not sure yet).
I've added a photo.

Crimping:  I will look into this.

T-202 (Asked by Ray F)  –  I will answer in a different thread.

I have to ask myself if I'm making a mountain out of a mole-hill.

The TBW was originally powered by an 800 Hz gas generator so a wide range
of filament adjustment was necessary.

My TBW will be powered off of 120 VAC house power which is a lot more
stable, so the range of adjustment isn't going to be that much.      The
Filament Rheostat is two of those pots mechanically linked together.
 Each is 12 ohms,  so the full adjustment range is about 2 to 24 ohms.

I was toying with the idea of just bypassing the one pot and using a single
pot that will give me 2 to 12 ohms adjustment.    That might be enough in
today's world.

Also,  I probably don't even need to use the adjustment!    I will be
powering the 500V and all filament transformers from 120 VAC, and the
output will probably be close enough to what is required that it won't
matter.   I'd like to use the Filament Adjustment as that's what was done
in the field.

As someone suggested,  I can always use a fixed resistor in series if
needed.

73 Mark K3MSB
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