This 4-channel mixer amplifier was found in an American publication from 1947. The circuit uses counterphase output tubes and a transformer power source.
The four gates of a 40111 IC are used in thes two-out circuit. The output chages their state in a...
This circuit was found in a 1980 publication. It uses only 3 easily obtainable transistors. It is a...
This circuit operates at a voltage of 1.3 V from a single mercury cell. We found in an old...