This two-transistor circuit was found in a 1966 US documentation. The power transistors are of the time. The system is intended for cars with contact breaker.
The astable multivibrator shown by the figure can produce signals in the 10 to 10 000 Hz band...
The diagram shows a tone control with the LM381 IC. The circuit is from a Radio Electronics from...
This circuit generates both white and pink noise. The transistors can be BC548 and the power...