Quote:
Originally Posted by Electronic M
The RCA method of building a chroma reference oscillator with feedback to correct phase errors (ie a PLL) was a gross over complication of achieving recovery of the burst reference carrier along with a color killer to switch off the color CKTs when the burst was not present...I like GE's method better: dump all that, and feed the burst to an RC tank circuit that will keep ringing until the next burst comes and use a limiter stage after it to keep the amplitude constant....It was like using the burst to strike a tuning fork, sitting back and listening to the tone.
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The problem with the GE idea is noise. RCA's system, like their horizontal
sync system ("Synchroguide") is vastly more immune to noise. This
of course does not matter to us today with signals from our local
NTSC generators fed over coax. But we here still have an OTA NTSC,
Ch. 39, and even at a (wideband) S/N < 1 (!) color and both syncs
are rock solid on my CT100.