The Home Automation Forum

MR26A Whole House X10 Receiver
by Rick LaBanca

I originally was going to review the Entertainment Anywhere kit from X10.com, but got sidetracked! This kit has the 800mhz transmitter/receiver pair that lets you send audio/video from your PC to a TV elsewhere. With the MR26a receiver, UR47A remote and include software, you could control mp3 or dvd player software wirelessly.

This worked as intended, with the exception of the remote being mislabled, and it locks up all the time. I probably have a defective unit, but never got that resolved. Not a bad kit, but for me I use the computer for other things, and unless you put in a new sound card, forget playing a game while someone listens to the mp3 elsewhere!

The interesting part

But the MR26a is interesting. It appeared to use the same frequency as the other x10 remotes and receivers. And since it hooked up to the serial port and had no dreaded housecode setting, could it hear all housecodes?

Well I've been lax lately and not keeping up! Over at the HomeSeer forum, long time Seer whiz Geoff Epstein had been decoding that sucker. He's come up with a great reason to buy the MR26a and HomeSeer if you're not already using it.

He's written an add-on to the latest HomeSeer beta, and it's brilliant. Any code the MR26a hears appears to HomeSeer as an X10 command coming in from say, the cm11a. That's all housecodes!

Why all the hoopla (or do I just not get out enough?)

For those unfamiliar to why this is a big deal here's the poop. X10's motion sensors and controllers send out any house code/unit number you want. Previously the only way to "hear" them was with a TM751 or RR501 reciever.

But those receivers would only hear one house code at a time. So in theory, if you wanted to hear three house codes because you have a lot of motion sensors, you would need three of these plugged in. Now only the MR26a is needed, with this software!

Why it's faster

Even if you're not all that heavily loaded, there is another advantage... speed. If you use your remotes to directly turn on a light, no computer, not much changes. But other uses do, you avoid sending things over the power line. Some examples:

Detecting motion and seer turns on some other light. The ---- lines indicate RF transmission (pretty fast) and === for powerline (pretty slow).

Motion detected, seer says "intruder alert"
Old way: Motion-A1ON------>TM751======>Computer-"intruder alert"
MR26A: Motion-A1ON------>Computer-"intruder alert"

Remote pressed, we turn on some different device via seer macro:
Old way: Remote-A1ON------>TM751======>Computer-B5ON======>Device
MR26A: Remote-A1ON------>Computer-B5ON------>Device

As you can see, you avoid transmitting over the powerline for the sake of the computer hearing RF remotes. That's a big thing. If you have a lot of motion detectors, this causes a lot of x10 powerline traffic, and possible collisions. The RF still could collide, but since it's faster I see it happening a lot less.

I've noticed that Geoff's software with seer is still faster than the TM751 for normal control. Say the TM751 is set to housecode A. I press A5On on my remote and the light comes on because the TM751 does it. This same thing using my pentium 2/400 actually is faster! So it's a win in all aspects.

Where do I git me one?

The MR26a is now available separately here for $30. It may be a better deal for you to get one of the other kits they sell that includes it.

Geoff's add-on to seer can be found in this thread at the HomeSeer site. And if you don't have HomeSeer yet, well... order it from this link to help support the site!

For Mac users, www.shed.com sells software for x10 control that supports it as well.