Frequency multiplexing system

TLDR: In this article, an amplitude limiting section and band limiting section on the video signal input side and the coupling section of video signals and out-band signals after the band limiting sections were provided to reduce bad influences to outband signals caused by the surge of video signal inputs.

Abstract: PURPOSE:To reduce bad influences to out-band signals caused by the surge of video signal inputs, by providing an amplitude limiting section and band limiting section on the video signal input side and the coupling section of video signals and out-band signals after the band limiting section CONSTITUTION:When frequency multiplexing is performed on a video signal of 4-MHz band and FSK signals having a center frequency of 6MHz and maximum frequency shift of 200kHz, an amplitude limiting section 1 and band limiting section 3 which stops frequency components of 6MHz+ or -200kHz are provided on the video signal input side and a coupling amplifier 2 is provided after the band limiting section 3 and frequency multiplexing coupling is made on the video signal and FSK signal Since the amplitude is limited by a surge limiter 1 when video signals are inputted and the higher harmonic produced then is stopped by the band limiter 3, multiplexed signals are coupled and outputted by the amplifier 2 without giving any disturbance to the FSK signals