Another K840CK15 Westinghouse restoration

[Electronic M]

Some tube based Ham radio linear amplifiers have ~1-5KV on the plates and use ceramic rotary switches to change plate coils for band switching. Such a part could work here.

After reading Ben's post I was thinking what if that 'stepped potentiometer' had a pot as one of its resistors, and a switching arrangement such that the pot would change positions in the string? If you did something like a 6-12 position switch instead of a 3 position you could use lower value resistors and potentiometer and have less drop on each resistor and less chance of switch contact arcing.

The following probably is not mechanically practical, but it would be interesting to mount the body of the pot to the shaft of the rotary switch such that when the pot is rotated to it's stop some additional force would click the switch to the next range in the direction you're turning it...Thus keeping the control on a single knob and retaining access to its full original range.

[ohohyodafarted]

So I did an ebay search in consumer electronics for "focus control"

There are lots of focus control assemblies for 70's-80's tv sets. However I am not at all familiar with tv sets of that era.

Here is a url to the search I did.

https://www.ebay.com/sch/i.html?_fro...LH_TitleDesc=0

It came up with a lot of hits but you have to sort through about 170 items. A fair number are focus assemblies for tv sets, but there are also some "Ford Focus automobile controls". The problem is that I haven't any idea if any of these would have resistance values near what I am looking for in the area of 50 meg.

Do any of you younger techs have experience with the actual values of pots in these tv focus assemblies.