How do I prevent radio interference from my new power meter?

March 23, 2011 8:23 AM

Recently the power company installed a new power meter in my home with a radio transmitter, which sends out a signal that meter-readers can pick up outside the house without having to come in and look at it directly. Here's the problem: I use a Tivoli PAL radio as my computer speaker (it's got an AUX jack and it's a great little device). But since the installation, it "chirps" every 30 seconds or so, presumably when the signal from the meter is broadcast. What can I do to stop this or shield my speaker?

I tried taking it apart but despite some visible screws it doesn't seem built for user servicing. The antenna is affixed with a TINY Phillips-head screw that is impossible to remove.

posted by saltykmurks to Technology (11 answers total)

You should give the power company a call and explain the problem. The FCC requires anyone with a transmitter to ensure they do not cause interference, which they clearly are doing. It's quite likely they've had to deal with this before.
posted by tommasz at 8:28 AM on March 23, 2011 [2 favorites]

I came to say what tommasz said. However, I'll point out that these days, regulations that demand something from companies tend to be ignored, these days. At least in America.
posted by Goofyy at 8:29 AM on March 23, 2011

Response by poster: I'm in Quebec. Hydro-Quebec is one of the craziest companies I've ever dealt with, so I doubt I'll get much satisfaction there. But I'll try!
posted by saltykmurks at 8:31 AM on March 23, 2011

These are common in Europe. They use a low-power GSM (actually GPRS) transceiver to report electricity usage.

It's actually a fantastic thing. It makes the local distribution grid much more efficient because you can see real-time power usage thereby allowing the power company to balance supply. It also obviates the annoying habit of the power company charging you for estimated use between readings. Also it saves energy in not having to have some person drive around and physically read the numbers.

That being said the interference problem is the same as with a GSM (AT&T/T-Mobile) cell phone. The easiest way to reduce the interference is to put some distance between your radio and the meter.
posted by three blind mice at 8:33 AM on March 23, 2011

Are you sure it's the meter sending a ping every 30 seconds ?

(The meters in our area respond to a wake-up signal from the car driving by taking readings, so they don't continually broadcast. Can you pick up the manufacturer of the meter and look it up to verify ? )
posted by k5.user at 8:35 AM on March 23, 2011 [1 favorite]

Response by poster: Yeah, I have no problem with this thing in theory. At the very least, it'll prevent me from having to let in the power meter reader in every couple of weeks (I once was going from my shower to my bedroom sans clothing when I noticed the lady at the door... TMI?)

@k5 It COULD be something else, but I did notice that it started the very morning the new thing was installed. Could be a crazy coincidence I guess?
posted by saltykmurks at 8:37 AM on March 23, 2011

It's most probably the regular GSM check-in. If you put a GSM cell phone right next to the speaker, you'd get the same effect. If you can't move the speaker farther from the meter, you could wrap the meter in tin foil to block the signal.
posted by Oktober at 8:57 AM on March 23, 2011

What type is this meter? Have they added an external monitor, like the Blue Line Power Cost or the TED Energy Detective? These devices chirp on 433.92 MHz about every 32s. This is a low-power, unlicensed, intermittent use only band (used for car door openers, wireless doorbells. etc).
posted by scruss at 9:00 AM on March 23, 2011

Response by poster: The brand is ltron.

I'm guessing it's a variation on this:

https://www.itron.com/na/productsAndServices/Pages/OpenWay%20CENTRON.aspx?market=electricity

(looks similar)
posted by saltykmurks at 9:08 AM on March 23, 2011

If you want to go the government complaint, the agency responsible for Canadian radio frequency allocations and interference problems is Industry Canada.
posted by thewalrus at 11:50 AM on March 23, 2011

You might run some experiments. Like Oktober mentioned above, wrap the antenna in foil to see if that helps. Wrap the entire device. If you can get it to where you don't hear the chirps anymore, you've at least identified the source of the problem. Next step might be to construct some kind of shield so that the RF goes only in the direction away from your house, so that the meter readers can still read your meter, but the RF doesn't saturate your house.
posted by babbageboole at 12:18 PM on March 23, 2011 [1 favorite]