Hi,

Trying to summarize and double check on what I learned from the above, old topic.

@yo-less

Is this HC-SR501 the sensor you used? I believe you removed the white dome, which happens to be the Fresnel Lens. Removing it might lower the detection zone and sensibility but it would be still good enough to do what you (we) need. That is how you manage to make it work through a hole as small as 2mm wide. Which wouldn’t be possible without removing the white dome.

Is that about right?

@dmcinnes

So, the microwave sensor is not directional but it detects in a radius manner; left, right, front and back. You were trying to lower the number of unwanted detection by using an aluminum foil around it. How well it did work for you? Does it still detects motion more than you want it to do?

Oh well, I wouldn’t mind a 2-3mm hole on the bottom of the frame if the microware sensor gives me too many false positives.

Thanks…

Re: PIR sensor behind glass?