This ultrasonic digital remote-control transmitter was found in the January 1976 issue of Radio Electronics magazine. The components are from the period. The IC is from the period.
This amplifier was found in a Japanese publication in 1972. Transistors are uncommon today, and...
The current of this source is 200 mA at the most, and the output depends on the zener that may...
Found in Mallory documentation from 1968 this circuit uses an integrated circuit from that time. The...