PURPOSE: To use only one oscillator provided externally by supplying a clock signal from a reference oscillator respectively to 1st and 2nd switched capacitor filters, frequency-dividing the clock signal and supplying the result to a modulation circuit using it as a prescribed frequency of carrier or spectrum inversion.
CONSTITUTION: The reference oscillator 10 generating a clock signal of a prescribed frequency such as 589.824kHz is provided, and the clock signal is fed to switched capacitor filters 2, 5 as the switching use, and the clock signal is fed to a frequency divider 11 with a prescribed frequency division ratio such as 1/180, where the frequency is divided into a prescribed frequency such as 3.2768kHz, and the signal having the said frequency is used as a subcarrier and fed to the modulation circuit 3. Thus, one oscillator is enough for externally provided, accordingly, the circuit constitution is simplified and the cost is reduced.
SAITO YUJIRO
YANAGIHORI MASAMI
| JPS58148541A | 1983-09-03 |
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