APPLICATION NOTE
6
Balanced Modulation
A balanced modulator produces a double sideband suppressed carrier signal (DSB-SC). By setting the offset of
the modulating signal to be zero in the above circuit, we will suppress the carrier. Notice, the output of this
modulator shown in Figure 9; the shape of its upper A balanced modulator output signal envelope resembles a
full-wave rectified AC source.
Figure 9: A balanced modulator output signal
Frequency Multiplication
Another application for a multiplier is as a frequency doubler (see Figure 10). Connecting a sinusoidal source
simultaneously to both inputs of a multiplier will yield a signal with double the input frequency. The first multiplier,
produces a waveform that has one-half the amplitude of the original input signal with a DC offset of one-half the
input waveform's peak value. The DC offset is removed with a voltage source called Voffset. The amplitude of the
original signal is restored with a second multiplier which doubles the signal.
