The difference between this circuit and the previous one is that it uses PNP transistors. The circuit is from Radio Electronics magazine from July 1968. The frequency depends on R1 and C1.
This circuit is from Mullard 1969 documentation. The circuit operates at a relatively high supply...
This circuit was found in the September 1984 issue of Radio Electronics magazine. The circuit has...
This circuit is regulated by zener and provides a voltage of 9 V. The circuit is from a Radio...