[murf]

Hi Guy's, I aquired a Westinghouse WR370 console radio and need to replace the on/off/volume control as it won't power up unless I put a jumper wire across the power side.
Looking at the schematics in my Riders volume 11, it shows no parts list. Need the specs for this control. Was replaced years ago(butchered) by some electronics wizard. I want to install a new or used control and patch up the wiring. I talked to one guy who said it is a 2 Meg max control. Not sure where that number came from, but I want to verify this before ordering a different control. Noticed that the control he put in there has the string of 3 lugs around the perimeter like most, but does not have the other single lug on the opposite side as shown on the schematic.
Any suggestions?
murf

[KCMike]

Hello, you might try amplified parts for schematics. It has 6 pages of your model.
One page of the schematic shows 2meg. with looks like 27 k tap on the vol.
Hope this helps.
https://www.amplifiedparts.com/schematic...52mGQfhRoM

[Arran]

Murf;
I found it here https://www.nostalgiaair.org/pdfs/Westin...-WR370.pdf The schematic says 1 meg ohm, shows it as R11. Since it's a tone control I think that you can use a linear pot, you don't need a log pot with an audio taper like a volume control. This set look a lot like my Canadian RCA 911K, motor drive, TRF amplifier stage, and 6F6s in push pull. https://pacifictv.ca/schematics/rca911kschematic.pdf some tubes are different though, and it has 12 as opposed to 11 because it has an extra IF amplifier stage. It has one odd feature, there was a switch on the back of the tone control that would allow you to widen the IF bandwidth for higher fidelity, I have seen this before but they usually have a separate control for "fidelity" not a two in one affair like this. Maybe there is a U.S RCA model that has better service info as I'm pretty sure that this is an RCA designed set?
Regards
Arran

[RodB]

I looked at the schematic and it shows the volume control is 2 meg with a tap. There is a 27k resistor attached to the tap. It doesn't show the resistance of the tap. I have seen other schematics with controls of this size that had the tap at 500k. One thing I don't understand in this circuit is the grounded volume control wiper. Maybe the dot is not a dot, but a smeared line cross.

[Arran]

Rob;
I'm thinking it could be bad printing or a drafting error as the RCA 911K shows a similar control, with tap, with the wiper connected directly to the grid of a 6F5, but it clearly shows a shielded cable, a ring with a ground symbol, not a black dot with a ground. It's a good thing Murf was asking about the volume rather then the tone control, replacing that would be much more complicated as it appears to have a double pole, double throw switch on it for the variable IF bandwidth. It's a cool feature but combining it with a tone control is kind of goofy, most sets like that had a "fidelity" control which was separate.
Regards
Arran

[DaleHCook]

The 1942 Centralab replacement guide shows their NT-152 as the volume control replacement, with their K-155 switch assembly. It is a 2 meg with a tap at 400k.

The 1946 IRC replacement guide shows their D-13-139X as the volume control replacement, with their 41 switch assembly. It is a 2 meg with a tap at 500k.

[RodB]

Hey Dale,

Can I correct those taps to be 500K and 400K?

Arran, Those diagrams tend to get fuzzy after the tenth iteration. Plus, the eyes aren't so sharp anymore either. I think that may have been a loop, then was filled in from copy to copy. That tone/volume circuit is very confusing, worse than the European ones.

[DaleHCook]

I had a rough day yesterday, and I'm slow getting going today. I've corrected it - thanks for the heads up.