This circuit was obtained from the April 1978 Radio Electronics magazine. The other circuit is a PLL of the time. The power supply must be 15 V symmetrical.
Found in American documentation this circuit uses transistors of the time. The circuit can be made...
This flasher with two power transistors was found in a Radio Electronics magazine from September 1961....
Found in American documentation from 1969, this circuit switches signals with a FET of the time....