This sophisticated workbench power source was found in 90s Radio Electronics. The maximum current is 15 A and the voltage can go to 37 or 42 V output.
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...