Found in 1965 Delco Radio documentation, this circuit uses transistors from that era. Modern equivalents can be used. The characteristics of the inductor were not given.
This circuit is from Signetics' 80s documentation. The circuit generates 100 kHz signals according...
This circuit was found in a Motorola documentation from the 90s. The transistor used is uncommon...
This two-tone buzzer can be powered by a solar panel. The circuit is from a 1991 documentation. The...