This circuit generates a siren sound. It was found in the April 1969 Radio Electronics magazine. The output signal is to be applied to an external amplifier.
June 2017 - Mouser Electronics already has to ship the new MC Crystal Real Time Crystal Modules...
The circuit below uses common JFET transistors, which can be the BF245 or MPF102 amplifying video...
This unregulated symmetrical power supply was found in the August 1982 issue of Radio Electronics...