Originally Posted by John Folsom

I have looked at 2 CT100 yokes, the part number stamped on teh body of the yoke is:

1106203-1, and the "other" numbers on each yoke are
274402 and 274412

"274" is RCAs manufacturing code, and the 402 and 412 are, I believe, date codes (1954, 2nd and 12th weeks).

JOHN,
SMALL POINTS, BUT JUST TO CLARIFY:

"If this is so, you yoke would have a date code of 1964, 35th week."
DID YOU MEAN 1954, 35th WEEK?

"I could not stand it, so I took the back off my CTC-4, and the yoke part number is 1106249, 274513."
AND, USING YOUR FORMULA, YOUR RCA MANUFACTURING CODE #274513 WOULD INDICATE 1955 13TH WEEK. THIS WOULD BE A YOKE INTENDED FOR EITHER A VERY LATE PRODUCTION RCA 21-CT-55 MODEL OR HELD OVER FOR AN EARLY PRODUCTION CTC-4. WAS THE THE SAME YOKE USED FOR BOTH 21-CT-55 AND CTC-4 MODELS?

"So I am thinking you have a nice CTC-4 flyback! What a great find."
I ASSUME YOU MENT YOKE AND NOT FLYBACK.

"Why RCA did not stamp the part noumer on the yoke which shows up in the parts list is a constant source of aggrivation."