This elaborate mixer is from an Electronics Today International from the 80s. Operational amplifiers are common and resistors with no value determine the gain of the amplification steps.
This circuit produces a signal in the range corresponding the the VHH channels between 2 and 6....
The circuit presented is from a 1969 Radiorama magazine (Italy), and can be designed with more...
The maximum power of the controlled load depends on the triac used. The circuit is from a Radio...