This flasher for incandescent lamps was found in Radio Electronics magazine from July 1968. The frequency and duration of the pulses are adjusted in R1 and R3 depending also on C1.
This is the power supply for the amplifier in the previous circuit. We found it in the same Radio...
We found this circuit in a 1990 documentation. It is totally up to date by the components it uses...
This circuit was found in a 1970s General Electric documentation. Transistors are uncommon today....