The ports used in this ultrasonic remote-control transmitter are TTL, requiring a 5 V supply. The transducer is a piezoelectric type, not very common today.
Found in Unitrode documentation from the 1980s, this circuit makes use of PUTs, currently common...
This bidirectional motor control was found in an 80's Electronic Engineering. The circuit uses a...
We found this circuit in the 1972 RCA Linear Integrated Circuits Manual. The circuit can generate...