A number of us here have either had--or have--some of the early solid state Zenith color sets with the flat, horizontal chassis, like the 25DC56 or 57, or 25EC58, or even the 1972 25CC55 chassis. Like most of the metal flat chassis Zeniths....ALL of them can be made to be relaible and produce a BEAUTIFUL picture.

But what about the 1971 solid state Zenith--the "40BC50" chassis?? I have NEVER seen one--and do not even know if they were sold for other than a 'field test" or such. One of my old Zenith manuals talks about the chassis--and it looks to be a LOT like the 25CC55 and 25DC56. But---in ANOTHER manual--for the 25CC55--it says the 40BC50 was NOT made in large numbers!!

Anyone here have any ideas??

Never seen one that I can remember, but might not have noticed if the appearance was similar to the 25DC56, et al.

Charles

I've been trying to solve the 40BC50 mystery for quite some time and with no success. The factory Zenith service manuals gives schematic, but does not provide a top view of the chassis or any of the additional chassis details as they do for the other more common chassis. I have a '71 Zenith brochure, there are two models that supposedly have a 40BC50 chassis, but they are high end cabinets and they only show the set with the doors closed. So who knows what the control panels really look like. The 40BC50 chassis also used an electronic tuner. It was a motor driven varactor type, but it looked very similar to the turret tuners and also had a rotating drum channel indicator. It was a totally different set up compared to the vertical channel strip motor drive varactors used on the later flat chassis sets that we are familar with. They picture this electronic tuner outside of the cabinet in the brochure, but theres no picture of the chassis in the brochure.

I'll have to post the '71 catalog later on.