| 摘要 |
radio engineering. SUBSTANCE: device has two scanning receivers, scanning control unit, operating frequency band noise meters, and reprogramming read- only memory circuit used to record data on separation frequencies for each broadcasting program. With device turned on to receive broadcasting program first receiver starts scanning at separation frequencies of this program recorded in memory and stops doing so as soon as noise level at its output reduces below permissible value. Signal is passed to loudspeaker. After that second receiver starts scanning at frequency of same program, Noise level at second- receiver output is measured at each frequency. Output noise levels of receivers are compared and if it turns out that noise level at second-receiver output is lower, its output signal is applied to loudspeaker and first receiver starts operating in scanning mode, and so on while this program is being received. EFFECT: provision for selecting programs with different separation frequencies. 2 cl, 2 dwg
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