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.
The critical components for this 1970s project are transformers. The original transistors are made...
Found in a 90s Popular Electronics, this circuit keeps an LED on when a phone is in use. Can be...
We found this frequency meter circuit in a 1974 documentation. The circuit is powered by 12 V and...