| 摘要 |
PURPOSE: A device for relaying a broadband/channel complex radio underground broadcasting signal is provided to convert an RF signal frequency into an IF signal frequency to amplify the IF signal frequency, and to re-relay by restoring the IF to the original RF, thereby rebroadcasting a program with the first delivered sound. CONSTITUTION: The first distributor(101) distributes RFs. The first to the fifth BPFs(Band Pass Filters)(102-106) pass FM broadcasting frequency bands only. The first attenuator(107) controls a gain of a passed FM broadcasting signal. An LNA(108) amplifies the outputted FM broadcasting signal. An audio amplifier(109) amplifies low frequency voice signals. The second distributor(110) distributes the voice signals. The first to the fourth FM modulators(111-114) convert the distributed voice signals into RF signals, and modulate the signals to output the modulated signals. The fifth FM modulator(115) mixes the voice signals with oscillating frequencies, and converts the frequencies into IFs. The first combiner(116) combines FM signals for emergency broadcasting. The third distributor(117) distributes the output signals of the fifth FM modulator(115).
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