Connecting my video monitor to the clamp’s output results in a distorted signal (as shown on the scope) and nothing visible on the monitor. But without the monitor, the signal waveform looks normal.
With a 0.1uF capacitor, the black level and porches look “tilted”, with the left end at a slightly lower voltage than the right.
With a 4.7uF capacitor, the tilt is no longer visible. Same with a 220uF cap. But still no steady video on the monitor.
Putting a 75 ohm terminating resistor in the circuit as I would have in a real circuit, halves the amplitude of the video signal. I’m guessing 0.1uF / 75 ohms as the input stage to a 2* op amp as I plan to use would be OK.
Seems a CVBS waveform can pass through a capacitor OK, but not with enough power to drive a monitor. It needs buffering.
Weka OSD 