This circuit is from a 1965 Motorola manual. It can be implemented with a common 2N2646 and a 106...
This 1967 Electronics World circuit is suitable for frequencies up to 1 MHz. The setting applies...
T1 and T2 can be BC557 and T3 a TIP32 for lamps up to 3 A. The supply is made by voltage of 12 V...
