Beacon with instrument (CB20495E)

This circuit causes an instrument needle to oscillate to signal an event. The circuit is powered by solar panel from 1 V.

300 mW FET FM transmitter (CB14882E)
This powerful FM transmitter with FET can reach more than 1 km in favorable conditions. L1...
Dual tone generator (CB21080E)
Found in Popular Electronics from the 90s, this circuit generates two tones that are selected by a...
Gas laser source with start circuit (CB7839E)
Found in a 73 magazine for radio amateurs of the 90s, this circuit provides a 2 kV voltage with 7.5...