It is a Smarthome X 10 switch. It controls a relay or receptacle somewhere, which will also be X 10. The relay can be hidden or in the form of a switch.

Not Smarthome. It's a Leviton X.10 transmitter, but other than that JoeFixit is right. It controls some other X.10 module somewhere. Either a light switch, a plug-in, or receptacle module or such.

If you never figure out what it controls, you can always install an X.10 device somewhere to use this.

Thank you both.

Guess I will be googling 'X 10 module'.

In a residence (custom built for an quirky engineer), what sort of applications would you guess it controls? The house plans had originally specified a heated driveway for example. But there is no indication that happened. Maybe it has to do with that exterior outlet that sometimes doesn't work. Or the motion sensor floods that also are unpredictable.

you can always install an X.10 device somewhere to use this Like a remote car starter?

www.smarthome.com is a good place to start. It's quite possible that your "intermittant" outlet is controlled my this. See if it comes on and off with this switch. He may have used it xmas lights or such.

Engineers are "quirky" only to those "civilians" who do not understand our highly evolved way of overcomplicating things. ;')

PS: Did you acquire this house because the engineer in question died in some highly unusual manner?... lol.

Celticmoon,

For the LOVE OF GOD, PLEASE stop opening and closing MY garage door. I'm begging you.

Sorry.....Couldn't resist.

Diyourselfer,

So THAT was what all that yelling was about...