We found this circuit in an old American documentation. The operational amplifier is from the time and the output used to control an SCR or other power control.
The purpose of this circuit is to restore the 0 V black level of an analog TV video signal at the...
The operational 3403 is not currently common, but a similar configuration can be made with modern...
This circuit can be tuned in a 100 kHz band around the frequency of the crystal. The transistor can be...