A couple of good ideas listed.
How far from the house to mail box, and is their electricity near mailbox.
I love the Linear transmitters and receivers.
I use a door/window transmitter on my van, when a door is opened, I am sleeping, it chimes the alarm tone on my keypads, the DSC panel has a keypad that can provide 4 different sounds for 4 different locations.
Also on boats, I use a Float switch higher than bilge pump float switch, so if battery, pump, or float switch fail, and water rises to 2nd switch which is connected to a DSC(can use other manufacturers or a Linear)door/window transmitter to transmit to receiver, add a AVD dialer, and it will call you and 7 others(anywhere in the world reachable by phone).
Plus you have 3 unused inputs for other things, 1 could be a contact from Time Clock, so everday at 3:00, the dialer would call you, also allow to listen in, and by pressing 2, you can have 2 way conversation(less than $150)
Could be handy to see the kids are OK, quit playing the video games, and get back to their homework. I know you would like it to latch so if visual or audible is not in ear or eyeshot, you will know of the event happened.
Also is the mailbox in view of front door?
There is also a set of photobeams that are the size of a regular sized LED(less than 1/4").
Let me give it some more thought, Take Care

Wow, thanks everyone for all the responses.

I have not had time to look all over, getting super busy at work again.

Feast or famine in my business. Got to grab the business while I can.

But Duh, mail box alarm. Go figure. I pride myself as a expert at searching the internet, AKA Googling, something about that word bothers me. OCD I guess.

But half the battle is to know what words to search for. Tried searching for Newspaper alarm, get some weird hits. I gave up after three pages. Went blank after that and reached out here where great advice and answers are the standard.

Eh um, little pat on self's back, thank you, no applause, just throw money.

OK looks like I definitely got some directions to go in, and some homework to do.

Thanks everyone and

Merry Christmas (yes even from a devout atheist, but still old fashioned)

And Happy Holidays!

I'm the expert googler. I've been told that. You can't have that title.

Stratmando did mention Linear. I was going too.

I do think that you may have to create a momentary contact from a maintained one at low power to preserve battery life unless we can come up with a "jiggle sensor".

SmallParts.com: The Hardware Store for Researchers and Developers is an excellent resource and so is Stock Drive Products.

Moisture, corrosion and the proverbial "5 finger discount" has to be considered. In any case you have a place to start.

You gave me an idea for a project that I don't have time for too, but would be worthwhile. A wireless separate refrigerator and separate freezer in the same room in the basement door prop alarm and a water alarm.

Thanks for the ideas.

Happy Holidays!

I was thinking about adding a chip such as this one http://www.st.com/stonline/products/...50/hcf4047.pdf to make a pulse out of a contact closure. Actually you would have to add a schmidt trigger as well and reverse engineer the circuitry just after the push button.

Here is a good Latching receiver:
Linear D-67L 1-Channel Latching Receiver: Internet Security Systems Inc.
Will get back on the momentary connection later.

Here is the other part that will connect to transmitter and provide the momentary contact:
http://atkinsonelectronics.com/product_pdfs/SSRM.pdf

With 24 V power and 7 mA power consumption, not likey to work with a battery powered transmitter. Besides it pulses on both the rising and falling edges.

Hence the question of Power near mail box.
As far as triggering on opening and closing, He would be better off resetting the latch condition AFTER retreiving mail.
TK, does your mailbox have a door, or is it the open tube?

Opened, also has several weep slots inside bottom.

No chance of power, anything would need replaceable rechargeable battery that could hold up to Maine winter.

I will go through all the ideas offered.In my mind, the remote unit could have a micro-limit switch on the bottom, as part of a RF transmitter sending a signal to a base unit inside.