Abstract :
The operation and results obtained with a representative selection of a.g.c. gate circuits are described. It is shown that a line-gated circuit is very susceptible to ¿lock-out¿ when large signal changes are made due to the loss of synchronization of the line time-base. The development of a simple high-gain gate circuit is described that is free from this fault and, in addition, permits improved video amplifiers to be designed.