This circuit was found in a Ferranti documentation from 1969. The transistors are common types of the company at the time. Smaller equivalents may be used. The output power is of the order of 150 mW.
This circuit was found in a 1998 documentation. It uses a sensor that detects the magnetic band of...
This circuit is from a Radio Electronics magazine from August 1990. The indicator module is of a...
We found this small audio amplifier in the November 1999 issue of Electronics Now magazine. The...