This 4-channel mixer amplifier was found in an American publication from 1947. The circuit uses counterphase output tubes and a transformer power source.
This circuit was obtained in a manual for radio amateurs from 1975. It is a circuit that allows the...
This is the circuit of a commercial radio sold in Japan in the 1960s. The IF is 455 kHz, and the...
In this circuit found in a Texas Instruments 2016 documentation we have an adjustment for the...