This circuit is from a 1977 Signetics integrated circuit manual. The output transistors can be BD136 and BD237 and the symmetrical supply can be from 6 to 12 V. The voltage gain is 10.
This infrared “radar” was found in a 2000 documentation. Its range varies between 20 cm and 1...
This circuit is from a 1974 publication, and the integrated circuit can be replaced by the 7905....
Using a tunnel diode, this circuit was found in a 1966 American publication. The circuit is for...