A multi-channel communication system including automatic station selecting circuitry and circuitry for preventing actuation of the station selection circuitry by noise or the like. The station selecting circuitry automatically, sequentially generates a plurality of local oscillator signals which are mixed with incoming information signals transmitted in one or more of the channels of the system. Whenever the frequency difference between an information signal and a local oscillator signal falls within the pass band of the receiving channel, a sensing signal is generated which stops the automatic station selector so that communications can occur on the selected channel. Circuitry is also employed to discriminate between noise and an appropriate information signal in the receiving channel so that the above-mentioned sensing signals are generated only when information signals are present.
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