This excellent 30 W tube amplifier appeared in the April 1963 Radio Electronics magazine that taught how to assemble it. The critical components in our time are tubes and transformers.
This bistable touch circuit using CMOS technology controls a relay. The supply voltage must be...
This project is from the book Science Fair Projects by Newton C. Braga. In it we have a relay that...
This circuit was obtained in an old documentation, but it is still current by the used components....