This siren configuration found in a documentation from the 1980s can also be seen in many of our projects and in this circuit bank. Transistors are common, but Q2 can be of power for a higher voltage supply.
This circuit is from a 1976 Motorola CMOS manual. It can be implemented with modern Darlingtons like...
The circuit presented is from a 1972 RCA technical documentation. The integrated circuit consists of a...
We found this transmitter circuit for different frequency ranges in a 1992 documentation. The...