This was at the back of home. There is no sprinkiling system. Looked like phone wiring and electrical wiring behind.
Thanks
Exterior ringer? Hard to imagine with cordless phones available but it’s a guess. 
Did you see where the wires were hooked up too.?
Marcel:) 
A lot of homes in my area have the water meter in the house and have an outside device that allows the meter reader to drive by and point his gadget at the device to get a reading. Could that be it?
It may be one of the earlier hard wired home weather stations. It looks alot like the one my Father-in-law has installed.
That was my thought as well.
Dave
How does the home weather station work? Why would a phone wire be used at a weather station?
Good call my thoughs to Roy
This could have been an older system . It would send A signal back to the recorder and give the temp none stop 24 hours a day . Most now are wireless I have one in my small Green house and it runs for about 4 months on two AAA batteries .
Many new door bells are also wireless like My car starters .
Always go out ot a warm car and clean Windows
Roy Cooke
Here’s a similar weather sensor. They can be visually very similar to the one’s used for lawn sprinkler systems (pictured second), but will have cables that will go to an indoor display unit or a PC.
http://www.weatherdownunder.net.au/images/tx4uo.jpg
http://www.irriguard.com/images/raingauge_t.jpg
There is at least one model of driveway sensor that will “beep” indoors when a car pulls in the drive that has a similar appearance.