Mitsubishi CS-1939 Tuner control Help

[Dan Schafer]

Hi All
Working on a Mitsubishi model CS-1939 circa 1986 color TV. I get only snow (has good raster) and no LED display and none of the buttons on the front keyboard do anything. The voltages to the tuner control are low and measure Ok when disconnected. I guess something in that circuit is loading it down, the sound level goes up and down every few seconds also (just snow in the audio), but audio amp seems ok. There is a 28 pin microprocessor upd-1709CT which seems to not have an NTE cross, & LA7910LED drive, LA7911 band switch low pass filter and a 2 character LED display. Does anyone have a troubleshooting suggestion before I send it off to a landfill? I'm at a roadblock. I like appearance of the blue phospher on the screen of the CRT when off...diden't they call those rare earth tubes?
Thanks
Danny in Cleveland