Trouble with a solid state boatanchor SW receiver's volume control

Howdy folks,

Maybe someone here can point me in the right direction.

I recently bought an RCA Strato-World Mark One solid state receiver for cheap because the owner said it wouldn't receive anything. Turns out, that's not completely true, but it's not working quite right either.

One problem I'm having is that there is little or no information on this radio anywhere. I can't find a model number on it, but that doesn't seem to matter because just searching by name doesn't turn up much. A schematic would be great, but so far, no dice.

The problem it's having may relate to the band switches up on the front panel. I can get it to pick up a strong FM station loud and clear. The problem is that the volume control does little to lower the volume. Turn it up, and it'll get louder, but turn it all the way down, and it's still playing at what's likely to be a robust mid-level of volume.

I can see the volume pot from the rear. And here's where a schematic might be nice. There are three wires coming to it from the power supply filter board, and another wire that disappears into its guts somewhere. There's a small green thing labeled R10 AM that may be a capacitor, and between volume pot and tone pot is a 560ohm 10% resistor. The resistor tests in-spec. Is the small green thing a capacitor, and could it be part of the problem?

As far as the rest of it goes, I'm not even sure how to remove the chassis from the case. This has to be the most complicated-looking thing I've ever seen. There are pictures available of the chassis out of the case, but no instructions on where to start with taking it out. I don't want to break something doing that, but imagine that the band switches at least need a good shot of de-oxit, and may even need their solder joints checked.

Any advice would be appreciated.

Thank you,
-William
 
This set is very interesting. Japanese OEM by Standard Radio of Japan (later became Marantz Japan, AK content there). Likely RCA trying to compete to some degree with Zenith's Royal 7000 line. Wish I knew where service information is. Appears from the links to be a well made portable of high quality.
 
The RZM198 isn't covered in Sams but other numbers around it are in the Transistor Service Manual (TSM) Series.
 
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