Vintage Zenith Snow

[Chad Hauris]

I would try and run the output of another known good set's tuner into the IF input of the Zenith (make sure neither one is a hot chassis set) This will tell you if it's a tuner or IF related problem.
Did the set ever have proper operation since you got it or did the problem suddenly occur?
If you have a decent strength UHF station available, does it come through OK or is it snowy too...this test will help rule out problems in the VHF antenna input circuit.

Haven't personally seen this problem in Zeniths but have seen it in RCA's which use a transistorized IF stage and the rest is tubes... the problem turned out that there was a power supply problem leading to abnormally low voltage supply to the transistor stages.