Does Anyone Know what this is?

[AKMike]

I have small metal box with some indicator lights on the top that is attached to one of my breaker panels.  There is no label or marking on it.  There is a small green light and a small red light on all the time.  I've been trouble shooting some x10 problems and I done know that this device is.  When I use my XPTT, there are two additional red lights that light up and blink on and off with the P1 On/Off signal.  It must be about 15 years old.  I suspect is may be a phase coupler.  I'de post a photo but I don't have permission yet.  The box is silver and about 4 inches square and 1.5 inches deep with a black top and has three wires into the panel.

[Brian H]

Doesn't sound like the XPTT companion receiver. As it plugs into a 120VAC outlet. http://www.authinx.com/pictures/xptt_xptr.pdf
The  X10 XPCR and Leviton HCA02 and 6201. All have plastic cases. http://authinx.com/manuals/X10/XPCR.pdf
I hope someone here can give you a better description as it does sound like a coupler repeater but a manufacturer I am not familiar with.

[AKMike]

I have the XPTR as well and I just happened to notice the blinking lights when the XPTT is plugged in.

[brobin]

Make one more post to reach 10 and then you can post a pic. Sounds like the box could be a whole house surge protector but that wouldn't explain the light responding to X10 signals.

[AKMike]

Here's the photo of the device.  It should be better than my description of it.  The green light and red light are on all the time.

[brobin]

IIRC, I once had one of those. It may have been made by ACT or Leviton and was a coupler/repeater. I'm basing that on memory of the shape of that case and LED's. Mine was a brown color but maybe the paint has flaked off yours. I remember that it was decent but not perfect and was replaced by an XTB-IIR which I still use today.

[Brian H]

If it is an ACT.
I looked at my ACT CR234 A10/X10 Coupler repeater. Tan case. Fits on a 4" square electrical box.
Green Power On.
Red Ready
Red Received a message
Red Transmit a message
Red Error indication.
Mine failed. The Red transmit led flashes but it has no output on one of the two phases.
Mine also has a fuse on each line input. Off chance the one not also supplying power has opened. As the green power led is on.

[brobin]

I had those too but the one I'm thinking about is an older model (CP001?) in an extruded aluminum case. I had it for many years but used it only a few and finally tossed it when we moved.  I think the lights worked the same.