This circuit was suggested by Signetics in 1980s documentation. The circuit makes use of the hard-to-obtain component of our day. It is for reference only.
The ports used in this ultrasonic remote-control transmitter are TTL, requiring a 5 V supply. The...
This sensitive circuit was found in old English documentation. Transistors may be modern...
This circuit was obtained in a 1976 English magazine, and can be assembled with equivalent...