Found in an American publication from 1969, this circuit can be adapted to be used as a shield. Operational amplifiers can be of modern equivalent types.
This low voltage lamp flasher can be powered from 12 V supplies. Frequency is adjusted by P1 and...
The transistors in this circuit, found in an American publication in 1975, can be replaced by...
This circuit, from an old publication, can also use modern transistors. Note that the unit is...