Thanks for the groups.io link, I am currently scanning it. I got the service manual for my unit and am reading through some of the testing portions. Playing around with the SME some more, I find that I DO in fact get output when the frequency is >1.5 GHz, but only when I have modulation turned on. Whenever the modulation is turned off I get the 110 Output Unleveled error. Without doing much digging, I am guessing that is an issue in a gain section somewhere? I am going to have to make my own extension cables for the 64 (I think) pin headers along with the coax (I saw somewhere on here I think someone had asked what the connections were, I will have to see if I can find the thread).
As for the screen, I see that I can get the exact replacement for a cool $500 USD, which I am not too excited about. My goal is to get this unit working as best as I can before I even consider buying a new screen, and before that I am going to try reseating it on the zebra strip to see if that fixes it. Until I get this unit working though I am not touching a thing on the display.
Anyway, does having the unit display the 110 Output Unleveled error only when modulation is turned off on higher frequencies ring a bell at all? For the most part, modulation off on frequencies <1.5 GHz seems to work, except for a section around 23.2-35.1 MHz, which seems like an odd value to me. Once modulation is on it is fine. I'm hoping the 3GHz card isn't dead, because it is showing some life atleast.