[Amps] AL1200 weak receive

[Ed Swiderski, KU4BP]

I have a confusing problem with my AL1200. During operation when the 
stdby/oper is on, the received signal is very weak. Switching back to 
standby and the signal level is fine. Checked the relay and it was 
operating correctly. Engaging with 12v applied to it. With no power to 
the amp and a rx signal going through, manually engaging the relay 
weakens the signal. Releasing it and it's back to normal. Cleaned the 
contacts using the method described by W8JI on his site. Still no go. 
Stumped on where to look next to track this down. A tests on another 
radio produced the same results.

With no power to the amp, I connected my RigExpert analyzer to the "RF 
in" and a dummy load to "RF out". Doing a sweep, the SWR reads around 
1:1. Engaging the relay by hand shoots the SWR very high. Goes back down 
when released.

That's the best symptoms I can give. Any suggestions would be an immense 
help.

Thank you,
Ed KU4BP