[Milsurplus] RBS Help Desperately Needed

[Joe Connor]

I desperately need some advice on an RBS HF receiver that I managed to convert from a working receiver to a non--working receiver. The link below is to the manual. the schematic is at p. 139 and the wiring diagram is at pp. 142-143.
Here's what happened: 
1. I replaced C-575, the screen supply filter and lost reception. No obvious wiring mistakes or anything like that. I assumed I had a bad solder connection on the replacement for C-575 or that I had broken a lead somewhere but I don't see anything. I even re-connected the original C-575 but that did nothing. 
2. A signal generator connected to the antenna produces a very, very weak RF signal at the tuned frequency. 
3. An IF signal injected farther downstream produces the proper tone in the loudspeaker and strong audio. 
4. I listened on a nearby receiver (SP-600) and can't hear the RBS oscillating. (I should hear it on the SP-600 1,255 khz higher than the RBS dial tuning, right?
5. I have voltages on V-501, V-502 and V-503, but the plate and screen voltages on V-501 and V-502 are a bit lower than spec (10% or so) and those voltages on V-503 are a bit higher than spec (10% or so). 
Any ideas or suggestions? It's just weird to me that it was operating great until I changed out that cap. I keep thinking that it had to be something I did in the changing out that cap, but I can't see anything. 
As always, thanks for your guidance.
                              Joe Connor

http://bama.edebris.com/manuals/military/rbs/


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