| 摘要 |
PROBLEM TO BE SOLVED: To provide a hot-water supply system having an intercom function capable of omitting manual adjustment of a voltage-controlled oscillator with high production efficiency and easy oscillation frequency adjustment at an installation site.SOLUTION: In a hot-water supply remote controller 2 having an intercom function for transmitting/receiving a voice signal with a frequency modulation method, there is provided a circuit for feeding back to a microcomputer 4 the output signal of a voltage-controlled oscillator 5 that generates a carrier signal to transmit a voice signal. The microcomputer 4 compares the fed-back carrier signal with a clock signal frequency, to automatically regulate a control voltage to be given to the voltage-controlled oscillator in such a manner that the oscillation frequency of the voltage-controlled oscillator 5 does not deviate from a predetermined frequency range. |
