A small audio test generator is very useful for quickly tracing a signal through an audio unit. Its main purpose is speed rather than refinement. A single sine-wave signal of about 1 kHz is normally ...

This article is part of the Ideas for Design Series: Vol. 3, No. 7. This simple, robust, and low-cost signal generator, based on the LM386 power amplifier IC, provides a trio of audio-band signals ...

Repairing radios was easier when radios were simple. There were typically two strategies. You could use a signal tracer (an amplifier) to listen at the volume control. If you heard something, the ...