[drh4683]

Jeff,
Zenith had their own version of the preset UHF, known as the "ultramatic UHF tuner". It was a very unique rather complex mechanical system, it was not controlled by buttons either. WHen the tuner was tuned to preset station 1, you would dial in the channel and that was it. Just continue that for all 6 presets and you were all set.
The way the tuner "memorized" the channels was by how much a set screw would pull/push a cam connected to the UHF tuning shaft. There were many return springs and loading springs. It was a cleaver system and looks pretty neat.
I have a space command 600 console with that tuner, and has a gear reduction for the UHF tuner as much torque is required to turn the mechanisem. When you change channels, you can watch the tuning knob spin fast 3 times while it advances to the next channel! Zenith introduced that tuner in 1968 for the 69 models and they lasted through around 1972. Some b/w zenith portables had the ultramatic but you dont ever see them. You dont see ultramatics on any zenith set. I immagine they failed as most of the mechanical components are plastic and broke. I had to fix the channel stopping lever on mine with epoxy when I first got it, the tuner didnt work. I assume the ultramatic TVs didnt last as long because of failures in the mechanics as the sets aged. Molded plastic mechanics insure failure. From the owners perspective, why keep a TV that you cant even tune! Figure most sets with the ultramatics didnt stay in homes as long as TV set with conventional tuning.

Anybody have an ultramatic tuning zenith?

Otherwise, I dont recall RCA having a mechanically preset UHF selector. Motorolas system works nice, just like a car radio. I think the ultramatic and the moto WID sets were the only preset UHF sets (that you could easily change the presets on. I know some sets you could get a UHF channel strip)