| 摘要 |
PROBLEM TO BE SOLVED: To avoid the interference of radio waves when data is transmitted from plural wireless sensors. SOLUTION: The plural series circuits of resistors and switches are connected to a modulation part 13 in parallel. Resistors r1, r2 and r3 are those for deciding the frequency dividing ratio of a frequency divider and the switches SW1, SW2 and SW3 are changed over by a manual operation. Thus, a transmission frequency can be switched by a manual operation by changing over the switches SW1, SW2 and SW3. Consequently, the mutual interference of radio waves transmitted from wireless sensors can be avoided by suitably deciding the transmission frequencies of the respective wireless sensors at the time of installing the wireless sensors. |
