Two-tone solar buzzer (CB20493E)

This circuit was found in a 1991 publication. The transistor can be a general-purpose type.

Monostable Using the 4098 [IV] (CB140E)
A fourth version of a non-retriggerable monostable is shown in Figure. It is triggered by the...
Infrared Audio Link (CB11967E)
This simulated circuit on the NI Multisim transmits modulated infrared signals with the audio...
Full wave control with SCR (CB21094E)
This circuit is from an American documentation from the 90's. The SCR can be of any type and the...