Tuning up a 1988 Zenith System 3 that I found.

[MRX37]

Originally Posted by zenith2134

Hmm, thats a headscratcher. Maybe the AGC control needs adjusting. Since you're running composite video through a modulator, the signal may be too 'hot' for the RF section of the Zenith. Worth a try...

Could I test that by attenuating the signal, say by running it through 100 feet of cable?

Still, the left side of the screen sometimes being brighter is more of a concern. is the video module on the main board itself, or seperate from the main board?

i'll snap a pic of the inside of the TV if it'll help.