Analog switch (double loop, double-break) and differential modulation amplifier complete the work. The carrier control switch, switch contacts in the time, from the inverting i
nput Chi input modulation wave is inverted. Back when the next carrier-inverting input, so that the anti- re going, to achieve the limit amplitude modulation, the carrier will not braid week and intermittent, but the polarity reversal. Analog switches must keep the carrier frequency, at high frequencies can not use. The modulated output is crossing the square, containing high frequency changed as needed to increase the band-pass filter, to obtain a sine wave signal.