Quote:
Originally Posted by NewVista
If feeding forward, C402 would be adding in-phase  What are they up to?
Through both stages, a lot of response tweaking  C401, C407, L401, L402, L403, C110, C404, L404, L405
I have to question how well ~1meg DC path can maintain clamped video |
I suspect there was a lot of fiddling to get a reasonable frequency responce and perhaps compensate for the behaviour of the delay line.
Besides adjusting the brightness by changing the second video amplifier bias, the brightness control also varies the amount of dc component fed to the control grid of the second video amplifier. R407, both halfs of R101A plus the resistor not depicted attached to the horizontal output tube negative bias form the divider chain. I think the 1 megohm dc path is not an issue because the input of the tube is high impedance at DC anyway.