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[Mike79]

Hello,

My issue are with the range of the CM15A and what are my options to fix it. My father-in-laws ranch home is about 70' x 50'. My ActiveHome Interface (CM15A) is almost 10' from the north and east wall of the home (only pc in the house). I have 4 Eagle Eye sensors (MS14A) I want to use for motion. One sensor (h2) is on the west end (in the center) of the outside wall about 70' from the CM15A. The second (h4) is under the deck about 20' from the CM15A. The third (h6) is on the deck about 65' from the CM15A in the northwest corner. The forth (h8) is 35' from the CM15A on the south wall and 10' from the east wall.

The remotes PalmPad (HR12A) only get a range of about 40' inside the home. So about half of the home doesn't get the range on sensors or remotes.

I have moved the CM15A to the other end of the home and tried the devices that didn't get range before and now do.

My sensors are on house code H

My indoor lamp modules are on house code C (for the remote)

My lighting macros are on house code J (use another remote)

My questions are...

1. Can i just get another CM15A and just use as a transceiver with no active home pro program loaded on it (no macros or timers).

2. Does X10 make a divice that will do the job, but listen to all the different house codes?

3. Is there an option or options that I'm not aware of for getting the signals passed via better antenna for the CM15A or whatever?


Thanks.

[dhouston]

The first and simplest thing to do is explained here...

• http://davehouston.org/X10_feng_shui.htm

If that doesn't cure your problems you can add RR501s or TM751 which are transceivers only.

• http://www.automatedoutlet.com/Home/Transceivers/X10-TM751
• http://www.automatedoutlet.com/Home/Transceivers/X10-RR501

You can also improve the CM15A antenna. Here's the antenna I recommend...

• http://davehouston.org/eggbeater.pdf

It is both simpler to construct and a better performer than other antenna recommendations. If you need range in the 100s of feet, you can add a wideband preamp to the eggbeater.

I had photos showing a CM15A with a 50-ohm BNC connector installed for the eggbeater but I'm not sure I can find them as I've lost a couple of NAS disk drives in the past few years and I think they were on them.

[Brian H]

There are a few threads here on getting more RF range with a CM15A.
Some are passive and only have some added wire wrapped around the plastic original antenna. To adding an external one.
http://forums.x10.com/index.php?PHPSESSID=r7jdfhd1qu3rmbo1s3j7k6r6d3&topic=19959.0
http://forums.x10.com/index.php?PHPSESSID=9n3j6g0pl4erfuh0ugqk1oj856&topic=18863.0

External antenna modification. Does void waranty as expected.
http://www.shed.com/tutor/CM15mods/CM15mods.html

The only other device I have seen that can do all 16 house Codes and Unit Codes. Is the WGL V572A.
There are some users here that have had good luck with a V572A.

http://www.wgldesigns.com/v572.html

[Mike79]

All,

Thanks for the replies!

So can I buy another CM15A for $50 (will it work with 2 in one house) or do i have to spend the money for antennas that might work?

[Noam]

Yes, you could buy another CM15A, but things can get tricky, because you don't want them to try to run the same macros, etc. The second one would really only be used as an RF repeater. You should look instead for an RR501, which is an RF receiver/PLC transmitter, that will take the RF signals, and send them down the powerline.

However, before spending any money, I recommend you try the "passive antenna mod" first.
It only takes a few minutes, doesn't involve any wiring or electronic skills, and (most importantly - for some someone at least) does NOT void your warranty.
Here is what you need to do:

1. Get an 18.5-inch length of stiff wire. Just about anything will do, as long as it is conductive (non-conductive things don't work well as antennas). I used a length of #12 electrical wire, but you could just as easily use a straightened coat-hanger, cut to length. Make sure it is straight.

2. Hold the wire alongside the CM15A's existing antenna, lining the end up with the "elbow" at the bottom of the CM15A's antenna.

3. Attach the wire to the antenna somehow. I used masking tape at first, then replaced it later with electrical tape (which looked much cleaner). Avoid using something metallic (like twist-ties).

That's it! The new wire acts as a "reflector," to capture the RF signals, and "bounce" them to the CM15A's antenna. There is no electrical (metal-to-metal) connection between the two.

Try that, and see if that improves your RF reception at all.

[Mike79]

Noam,

Thanks for the "passive antenna mod"! That increased the distance by about 25%. I now can get by with one CM15A and one transceiver for the far motion sensors.

[Noam]

Only 25%? I would have expected better results. Are you sure the wire is 18.5 inches long (not 18, not 19)?

[dhouston]

Thanks for the "passive antenna mod"! That increased the distance by about 25%. I now can get by with one CM15A and one transceiver for the far motion sensors.

Have you tried the technique shown at http://davehouston.org/X10_feng_shui.htm? If you do this to the motion sensors you will likely have sufficient signal strength.

And, I've done extensive hands on tests with metered results. The length of the wire is not critical. Orientation (horizontal, vertical, 45°) might make some difference - some users say it did - I saw little difference.

[Noam]

Thanks for the "passive antenna mod"! That increased the distance by about 25%. I now can get by with one CM15A and one transceiver for the far motion sensors.

Have you tried the technique shown at http://davehouston.org/X10_feng_shui.htm? If you do this to the motion sensors you will likely have sufficient signal strength.

And, I've done extensive hands on tests with metered results. The length of the wire is not critical. Orientation (horizontal, vertical, 45°) might make some difference - some users say it did - I saw little difference.

I thought the 18.5 inches was important, because it is the half-wavelength of the RF signal frequency.

[dhouston]

I thought the 18.5 inches was important, because it is the half-wavelength of the RF signal frequency.

In theory, it is but practically, for a receiver, neither it nor slight impedance mismatches (input impedance to nearly all receivers is 50-ohm but using 75-ohm F connectors and 75-ohm coax usually works well enough in most cases), make a lot of difference. You'll likely see more variation from antenna orientation, people moving about, etc. That's not to say it shouldn't be in the 18-19" range - just that the exact length is not critical.

There are also differences in the wavelength in free space and in the wire so even the theorectical length is a bit shorter.

• http://www.qsl.net/ag4ty/wavelength.html

[Noam]

Oh, I agree that location and orientation of the antenna play a big part in it. However, He will probably get better results from an 18.5" length of wire, than he will from a 21.5" or 15.5" length, right?

[dhouston]

Yes.

If you followed the link to the antenna calculator, the recommended length is 18.116129032258065". I generally recommend 18 and figure most of us will have trouble accurately cutting it within 1/10 inch, anyway.

[Mike79]

All,


By no means am I disapointed with the results of the wire. This worked great! I now can get the remotes to work in about 90% of the house and 98% of the areas it would be used the most. I did follow Noams advice and it is 18.5 inches long and taped with electric tape right at the elbow of the CM15A. I can shorten it 4 tenths of an inch if that will help but I know now that I can't expect it to get a siginal from an eagle eye at almost 90' from interor and exteror walls. I was concerned about the pc and other hardware around (blocking the signal) so I used an extention cord to place the CM15A above the computer desk. 

[dhouston]

...I know now that I can't expect it to get a siginal from an eagle eye at almost 90' from interor and exteror walls.

If you follow the advice in the link I've posted twice and also add a passive radiator to the EagleEyes you might get the range you need.

And trimming the wire by 1/2 inch is unlikely to make much difference.

[dave w]

I know now that I can't expect it to get a siginal from an eagle eye at almost 90' from interor and exteror walls. I was concerned about the pc and other hardware around (blocking the signal) so I used an extention cord to place the CM15A above the computer desk. 

http://www.wgldesigns.com/v572.html