rain sensor capacitor role

Thread Starter

Volttrekkie

Joined Jul 27, 2017
60


Hi. In this circuit, what is the role of the capacitor? I can see that BC548 turns on BC558 which turns on the speaker. But what does the 0.1 capacitor do?
 

benvolz

Joined Nov 23, 2017
8
bit of a stab in the dark here but may be to make the sensor less pron to false alarms in the case of say high humility and other factors ? may be some one else can correct or confirm this as i would also like to know as well.

just a head up and you may already know this but if your making a rain sensor you will also need a heating circuit.
 

Thread Starter

Volttrekkie

Joined Jul 27, 2017
60
Capacitors allow ac and block dc. I am guessing that the Prob when wet with rain sends an ac signal through the capacitor to the speaker. This changes the sound of the speaker. Am I correct?
 
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