Quote:
Originally Posted by Electronic M
The 2 things that have to jibe (assuming a transformer powered set) are video polarity and amplitude at possible injection points relative to the composite video standard. If either is wrong/not close it could be fixed with a user designed video amp or attenuator, but that can get complicated....
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Yep. Fortunately the RCA 721 chassis (and most other early RCA sets) make this really easy, with the first video grid needing negative sync, and ~1vpp signal level, exactly in line with a standard composite video signal level from modern gear.
If you need to invert the signal, or adjust the amplitude, you can always build a suitable preamp using either a period-correct tube, or a modern video op-amp like an AD811.
Don't forget that a composite video input is supposed to present a 75 ohm load to the video source. This usually takes the form of a simple 75 ohm resistor from the input of a high impedance stage directly to ground.