[Tomcomm]

Wayne. I understand the original RCA CTC2 chassis was a true I-Y/Q-Y axis chroma 90 degree quadrature demodulator system to precisely recover the two chroma components in quadrature sent by the transmitter.. However the CTC2B chassis is a R-Y/Q-Y chroma non-90 degree axis quadrature demodulator system. Seems "The General" ordered RCA engineers to adopt this "buggered" quadrature demodulation system on the CTC2B to avoid paying a license fee to I believe Philco. The R-Y axis is 90 degrees from the reference burst and 33 degrees from the proper I-Y axis, any inherent R-Y demodulator component errors could be "mostly" removed by resistor changes in the chassis's low level matrix system. My Sept 11,2007 21CT55 reactivation project notebook indicates I considered the modification of the CTC2B's irrational R-Y/Q-Y matrix to the CTC2's proper I-Y/Q-Y configuration a no-brainer, accomplished with the addition of 2 resistors as shown in Oct 13,2007. This was the first of many "experimental" modifications I would make to this chassis. I had already exchanged the original 21AXP22 for the much brighter 21FBP22A rare earth in 1965 and made no suggested chassis changes to compensate for differences in CRT brightness. The picture quality of the present 21CT55 is quite acceptable but could possibly be better with a rigorous colometry alignment in the near future.....Tom