The 1974 Zenith Chromacolor 4-tube hybrid console w/ Space Command 500!

[Findm-Keepm]

Originally Posted by drh4683

As stated before, the chassis itself being the 23EC15 marks the very last color chassis using tubes in Zenith production. This set was built in Chicago, but by 1974, Zenith had their own feeder plants operating in Mexico which built deflection yokes and duramodules. Zenith's plants in Mexico would soon take on more and more production. The RUN number as seen on the cabinet model tag displays "410C" which means final assembly of the set was on the 3rd day of the 10th week of 1974, or more precisely, March 5, 1974.

[

Why are the julian dates on modules / brackets AFTER March 5th? One module has a julian day of 4083 (March 24th) and the bracket above the remote channel indexes shows 4074 (March 15th). The final chassis stamp to the right of the fly shows 4102 day, or April 12th, 1974.

We used the julian day on the modules as a "serial number" when selling rebuilt modules - a tactic stolen straight from Zenith.

Zenith used internal julian dates on assemblies, and of course individual parts were marked IAW EIA procedures. The transformer was made the 10th week of 74 (March 3-9), so kinda tough to get it across town to Zenith and through all the wickets by the 5th...

I'll try to find the training manual that explained the date markings on Zeniths - it's around here somewhere.