This TTL circuit was found in a 1978 technical documentation. The power must be supplied with 5 V. It converts ASCII characters to hexadecimal.
This circuit was obtained in the publication 101 Electronics Projects of 1979. The circuit can be...
This circuit was found in 80's Popular Electronics. Transistors are commonly used. The...
We found this circuit with 5.3V zener in a Philips publication from the 60s. The op amp could be a...