Detection unit
of the ultrasonic alarm(1)
I made a detection unit, dividing it into two printed boards. Because the receiver circuit of the ultrasonic amplifies a reception signal by about 1000 times, it has the possibility to malfunction with the noise when the output relay works. Therefore, I mounted an output relay on the another board. There may are not an influence if strengthening grounding and not mounting a relay near the input circuit of the receiver. |
