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 simple oscillator is yet another of the many versions of sonic insect repellent that we find...
The circuit in the figure operates at frequencies from 4 to 20 MHz and also uses a common junction FET...
This TTL counter was found in the April 1979 issue of Radio Electronics magazine. The circuit is...