I tested a TR Version 1 in place and it never missed a signal (V1 has a metal plate just below the pushbutton that was supposed to improve signal reception). I drilled a pinhole in the little arm that sticks out of the rear of the switch when on. For linkage, I used 10-pound braided fishing line. The 'flag' was a steel washer. Works! The washer drops a distance of 20mm.
All I need to do now is 3d print an enclosure with a shield to block seeing the flag when the switch is off.
You might want to check to see if this violates postal law before doing it. There's laws around mailboxes, and a flag usually means "there's outgoing mail to pick up". Having an automated flag for "there's inbound mail to collect" notifications is probably illegal.
Yeah, I was askedabout it during the pandemic. Actually, it was the contact sensor in the big package dropbox located beside the garage that caught the mailman's eye & interest. The sensor in the door of the mailbox is particularly obvious but it had been there a few months before questioning about the dropbox. With hindsight, I agree that the sensors look like they could be booby traps. Basically, I think the carriers haven't cared and let me slide.
The TR flag could be mounted somewhere away from the mailbox but still visible when I pull in the driveway. I'll beg forgiveness and do that if they grumble about it.
The Zooz sensor s on a magnet, so it gets knocked off once in a while, but if there's an issue with the battery, or whatever, it can be brought into the warm house.
It does look a little like a camera though.
Then again, now I get a picture of my package at the bottom of the bin from FedEx or UPS, maybe both, lol.
