Affordable Bimodal Optical Sensors to Spread the Use of Automated Insect Monitoring

Figure 25

Low-pass filter. The low-pass filter accepts input from the output of the demodulator. It filters the signal so that the audio signal is accepted, and the high frequencies of the demodulator output are rejected. It is composed of two stages, IC6A and IC6B. The IC6D provides the required DC reference voltage at VCC/2 level.