Nightly noise interference

I have had X10 installed in my house for years. Within the past couple weeks, I started noticing that at night, a lot of my X10 stuff wasn't working. I've done some investigation with my ESM-1 meter and have found that one leg of the house is experiencing outrageous noise levels. The meter shows a steady reading of over 50%. The other leg is fine. My front porch light is scheduled to come on around 1/2 hour after sunset and that seems to work most days, but it will never shut off because sometime after that this huge noise starts. I have a coupler-repeater installed, but the noise is too great and it doesn't help.

I don't think this is coming from my house. Nothing much changes here between night and day except for a few lights, but I'm sure they aren't causing the problem. I'm guessing it has to be a neighbor, probably close, right?

What can I do about this? I have a Panamax whole house surge suppressor which has not been installed yet. Would that be able to block noise coming from outside, or do I need some other kind of whole house filter?

Reply to
brucehvn
Loading thread data ...

If you have a repeater, why is the noise only on one phase of the service?

I don't think this is coming from my house. Nothing much changes here between night and day except for a few lights, but I'm sure they aren't causing the problem. I'm guessing it has to be a neighbor, probably close, right?

What can I do about this? I have a Panamax whole house surge suppressor which has not been installed yet. Would that be able to block noise coming from outside, or do I need some other kind of whole house filter?

Reply to
Josepi

Because his repeater repeats X-10 commands, not noise. A repeater is more than a device that just bridges the phases at the X-10 frequency.

Reply to
greenpjs

The OP's coupler does that. I assume, if the OP has a meter then he knows the difference.

On Wed, 17 Nov 2010 13:09:20 -0500, "Josepi" wrote: If you have a repeater, why is the noise only on one phase of the service?

Reply to
Josepi

He said "coupler-repeater". I assume it's really a repeater. Of course, I could be wrong, but that explains why the noise isn't being bridged to the other phase.

Regardless, I would pay attention to what comes on when the noise starts. Maybe a nearby street light on a photocell connected to the same transformer.

Reply to
greenpjs

Don't be so sure that the problem isn't in your house. You said that the last thing that works properly is the lights turning on. Lights can cause electrical interference. LED, CFL, and other types of lights can be the culprit. Try turning each one off, then see if it improves.

I would think that if it external to your home, it would appear on both phases of the power line.

Set up the meter, and watch it to see when exactly the noise begins. That may be a good clue to the problem.

Reply to
Jim H

I agree that it is likely to be internal. Things like furnace blower motors, which have been idle during the summer, can be a noise source like this. A new or failing CFL or anything new with a Switch Mode Power Supply might be the culprit.

Reply to
Dave Houston

I had a fluorescent worklight that showed absolutely no noise when I tested it when I first installed it, but as the bulbs aged it began to "sing" loud enough at 120KHz to drown out all X-10 traffic on that circuit. You need to measure the noise at several points to determine the source. It will be greater as you approach the source. If the noise level is loudest near the circuit panel, it means either your repeater has failed (likely) or that the noise is coming from outside (less likely). The ESM-1 is not the tool for this, unfortunately, because it's got a bar graph readout. Devices like Jeff Volp's XTBM or the Monterey PSA are much better suited to noise hunting because they provide a digital readout of the noise making it easy to trace along a known circuit, outlet by outlet, to locate the noise source. Since your noise is restricted to one side, I am betting on a bad repeater. Power it down and then measure.

-- Bobby G.

Reply to
Robert Green

Cabling-Design.com Forums website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.