We found this circuit in a 1969 General Electric documentation. The circuit uses transistors of the time and the diodes in the dotted board must be mounted on the output transistor heatsinks.
This 1995 circuit uses an audio amplifier that is no longer common today. However, other...
The tone produced by this circuit attract fishes. The circuit is installed into a small can and...
This circuit is from Mullard 1969 documentation. The circuit operates at a relatively high supply...