Double balanced modulator
In the note I. Suliko (RJ8JCW) and A. Goncharov (UJ8JKD) "Double balanced mixer", published in the magazine "Radio" (1984, No. 10, p. 21) described a simple node on the chip CHA. Even more simple device of similar purpose without inductors is obtained using the chip CAR (see diagram).
When the input signal frequency of 1000 kHz and 30 mV at the output of the Electromechanical filter 71 is present single-sideband signal voltage vacuum of about 2 V. the Carrier frequency is suppressed by at least 50 dB.
When creating a node of the modulator balance trimpot resistor R1. The required level of SSB signal at the output node-set variable resistor R6.
Authors: A. Kartavtsev (U3QCX),ENIN Y. (UV3QG), Voronezh; Publication: N. Bolshakov, rf.atnn.ru