RFDx, you are a God send!!!! Thank you very much indeed!!! That is identical to my unit. I am servicing module by module. The PLL #1 was going in and out of lock. It had a bad 4558 / 1458 dual opamp messing up the loop control voltage. It is fixed and working well. I also replaced the filter caps for the 5vdc regulator in the PLL #1 module. It never had any bulk capacitor on the 5 volt side of the 7805. Also, the PLL #1 ONLY gets power ground through the mounting screw!!!! Wow, bad design!! I am so anxious to get this thing running. It does have R.F. output but very erratic due to two of the PLL's still being unlocked. Thanks again!! I'll report the progress.