Alas my good man , this is were I deter to you and your expertise. A decent Amateur radio receiver I never had or worked on . I did have an entry level job after High school and tech school testing the Collin’s R390 /u for Barker and Williamson , 800 of them for every function. Then as soldier in Nam I worked in Signal corps and was assigned to the AN/ GRC-26.
Radio rf gain should have been full clockwise when you zero S meter. The receiver is still not receiving as should. Check spects for rf level for sensitivity. I believe it is still not functioning correctly.
That SX-122 is still far from right. One thing that I saw was one of the 1650 IF cans the radio hummed when you touched the top alignment screw, Also your rf generator is not good. Good luck.
