Found in Radio Electronics from the 90s, this circuit is intended for analog TV applications of the time. The transistor used as well as the module are uncommon components today.
This buzzer with the 555 was suggested by a Popular Electronics from the 90s to be used as a...
This is the receiver for the previous circuit found in the November 1991 Radio Electronics...
In the figure we have the configuration of series regulator protector suggested by Motorola in 1968...