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Bird scarer

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New Member
So I'm trying to get a bird scarer done with the use of a 555 and RCWL-0516(microwave sensor) and a 9V solar panel , but I can't figure out how to properly implement the RCWL into the circuit.
I was thinking about doing it with an Arduino, but from what I've read it should be able to work with a 555 IC + I'm not sure if the 9V will be enough

I know that the diode will take +- 0.7V (I put it there to stop reverse voltage, yet I dunno if it's ok)
I'm also not sure about the resistors and capacitators, cuz I tried to re-do a timer circuit.
And also I dunno if the RCWL should be connected as it is.

Thanks for the answers


Well-Known Member
Most Helpful Member
Note that the RCWL-0516 "Vin" must be 5V within a few percent; you cannot run it directly from a 9V solar panel.
If it has been connected to 9V it may have been damaged.

Add a decent size electrolytic capacitor between Vin and GND; GND should be connected to the overall ground and 555 VCC should also go to the 5V supply.

The OUT terminal should feed the resistors linked to the 555 to enable/disable oscillation.

For the 555, the "discharge" pin should be linked to the junction between the two resistors, or it will not oscillate.
See some of the examples here for more info:


New Member
Thanks, I've finished it based on what you wrote and also based on those instances, I haven't yet done anything aside from designing.
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