This is a field strength meter found in an 80's Hands On. The circuit operates at frequencies up to 500 MHz and has a buzzer as its indicator. Can be used as a detector for spy transmitters.
This circuit was found in a 1966 EEE. What it does is it converts the logic levels of 0 V and +4 V...
This circuit is from a 1976 documentation. It makes use of isolated gate MOSFET which is already very...
This interesting effect circuit was found in a 1982 publication. The sequence of musical notes is...