[Premium-Rx] WJ 8618B(S1) spectrum monitor schematics and manual?

[Peter Gottlieb]

The spectrum display in my 8618B(S1) has gone flaky and very dim. It's not the 
CRT, I tried a spare.

I've discovered the manual, and options manuals, don't have anything on the 
display section.

It is called out as:
Signal Monitor Assembly 794103-1
Schematic 470212

Does anyone have further info on it?  It would be MUCH appreciated! I'd like to 
troubleshoot then properly adjust it.

TIA,

Peter