Thanks, @tomkxy, fantastic! I will be trying it our shortly, as soon as I got those PIRs working on 3V.

Thanks, @LastSamurai! I have ordered a few to try them out. (Not sure about the question about AMS1117, hopefully there are someone here who are.)

@tomkxy: Have you gathered some experiences with this setup over time? And would you mind sharing the Arduino sketch you are using?

I am hoping to do more or less the same with Sensebenders and PIRs, and I am new to electronics of this sort.

Hi! I have just gotten four Sensebenders and was hoping to connect PIRs to them and powering them with AA batteries. I understand from the forums that people do this. But is there a working Arduino sketch example implementing a PIR for wake-up out there? (And perhaps there is a more detailed description for such a hardware setup for us newbies?)

Thanks for sharing, @therik. Where can I get the high-ripple-rejection-ratio regulator you are describing? I cannot find an FT531IA on Ebay. (Or if therik is no longer following the topic: Anyone else know a specific regulator I gan get from Ebay?)

Thanks in advance.