This TTL shield with high level logic is from the LM111's own 80's manual. The integrated circuit is no longer easily found, but the circuit can be adapted to use modern equivalent operational amplifiers.
This configuration is from a 1987 publication, but it can be easily assembled today, as the...
This is a simple source indicated for powering low voltage projects on the bench. The circuit is...
This circuit is from Philips' 70s documentation. Transistors can be replaced by modern...