This electronic Morse Key for telegraph message transmission was found in an American 1980s amateur radio documentation. The circuit uses TTL technology and must be powered by a 5V voltage.
This ultra-simple tester and component gauge lets you perform continuity testing and even evaluate...
The circuit is from a June 1995 Electronics Now. The relay is power-dependent and both R1 and R2...
The PA222 integrated circuit used in this project from an American 1967 documentation is not...