After some more poking trying to test the relay, I discovered that the RPP relay, K1, was OK. Let's say I have egg on my face!
It turned out to be an intermittent connection inside the electronic attenuator where the 1GM1-4200 module mates to the SMA(f) connector that is driven by the RF board. It's possible to not tighten this correctly if one is not careful or forgetful. I might have had a small gap in the mating of these two SMAs which was temperature/mechanically sensitive etc causing a poor connection. During the last couple of days I have had no problems over multiple cold starts and exercising its functions. Keeping my fingers crossed. I made a YT video if anyone is interested in seeing the details:?https://youtu.be/krQaOhuTTGA
