Audio Devices

The kit contains 4 audio devices:

• 2 microphones with different size and sensitivity
• an active and a passive buzzer

The microphones are mounted on the same PCB as the analog devices and the comparator can be used to switch on an alarm (including the green LED) when the noise level surpasses a threshold given by the potentiometer

small microphone	big microphone

The passive buzzer works like a load speaker and needs a frequency as input signal to work. Changing the frequency will change the pitch.

The active buzzer just needs a DC signal to work. This means that you just apply a DC level between S and - to make the active buzzer work while you must generate a frequency on the S pin of the passive one. "-" is connected to ground.

active buzzer	passive buzzer

-- Uli Raich - 2017-01-10

Comments