This circuit was obtained in a 1980s publication, but it can be easily assembled today, as all components are common. The transformer is 12 + 12 V with at least 1 A and the diodes 1N4002.
This circuit was found in a 73 amateur radio magazine from the 90s. An LED extends the scale from 0...
This small inverter that produces high voltage from a 6 V source was found in an American...
This circuit was found in a 1967 Philips publication. Transistors support equivalents and modern...