Thats the first gen for this cabinet. The 14A9C50 does indeed use the 221-39 demodulator IC (in the form of a 9 pin miniature tube). I have this same set but it has the 20CC50 chassis for '72. The 14A9C50 is another chassis I hope to add to my collection one day as the 1970 Zenith's are my favorite year of all.
Heres my 20CC50 version to compare and this was the end. By 73 the only fully loaded up tube type TV's were the 16" portables. The consoles and large table sets like these had all gone solid state or were 4 tube hybrids by 73 as well.
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