# Can a street light really disrupt my DSL signal? **URL:** \ **Category:** Factual Questions\ **Created:** [April 5, 2003, 5:46pm UTC](https://boards.straightdope.com/t/can-a-street-light-really-disrupt-my-dsl-signal/166697 "2003-04-05T17:46:52Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![NinetyWt](https://avatars.discourse-cdn.com/v4/letter/n/cc9497/32.png) [@NinetyWt](https://boards.straightdope.com/u/NinetyWt)\ **Post date:** [April 5, 2003, 5:46pm UTC](https://boards.straightdope.com/t/can-a-street-light-really-disrupt-my-dsl-signal/166697/1 "2003-04-05T17:46:52Z")
My DSL goes out every night, around 6 pm. It’s back on in the a.m. I contacted BellSouth and the tech told me it could be the street light in front of my house. :dubious: Could this be true? Here’s what he said: > [@](#): > > Not necessarily the timer but just the light coming on itself creating and electromagnetic interference that is strong enough to disrupt the DSL signal. which in turn makes the READY light start flashing on the modem I plan to watch tonite to see when the light comes on, but this seems like horsefeathers to me. ---
**Author:** ![Declan](https://avatars.discourse-cdn.com/v4/letter/d/ecae2f/32.png) [@Declan](https://boards.straightdope.com/u/Declan)\ **Post date:** [April 5, 2003, 5:52pm UTC](https://boards.straightdope.com/t/can-a-street-light-really-disrupt-my-dsl-signal/166697/2 "2003-04-05T17:52:30Z")
Or you have zero shielding either in your house , or on bells end from the trunk. Declan ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [April 5, 2003, 5:55pm UTC](https://boards.straightdope.com/t/can-a-street-light-really-disrupt-my-dsl-signal/166697/3 "2003-04-05T17:55:27Z")
[quote] Cable line noise, or ingress, can occur anywhere, from inside a neighbor’s house, to anywhere on the line, to a streetlight’s bad transformer that leaks radio frequency near a cable line every time it goes on at night.[/qupte]From [this article](http://www.techweb.com/winmag/columns/broadband/2000/21.htm). Yes, a streetlight _can_ cause problems. ---
**Author:** ![NinetyWt](https://avatars.discourse-cdn.com/v4/letter/n/cc9497/32.png) [@NinetyWt](https://boards.straightdope.com/u/NinetyWt)\ **Post date:** [April 5, 2003, 6:11pm UTC](https://boards.straightdope.com/t/can-a-street-light-really-disrupt-my-dsl-signal/166697/4 "2003-04-05T18:11:46Z")
owie ~ zowie !! What should I do ?? ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [April 5, 2003, 6:19pm UTC](https://boards.straightdope.com/t/can-a-street-light-really-disrupt-my-dsl-signal/166697/5 "2003-04-05T18:19:37Z")
If you can verify from the timing that it is, in fact, a streetlight you can try contacting your area’s power utility, and ask them nicely if they can look into it. ---
**Author:** ![NinetyWt](https://avatars.discourse-cdn.com/v4/letter/n/cc9497/32.png) [@NinetyWt](https://boards.straightdope.com/u/NinetyWt)\ **Post date:** [April 5, 2003, 6:22pm UTC](https://boards.straightdope.com/t/can-a-street-light-really-disrupt-my-dsl-signal/166697/6 "2003-04-05T18:22:11Z")
Ya know, **Q** , that article was about cable modems. They talked about the cable company changing out the cabling. I wonder if BellSouth would replace the line? Heh. Or if I should re-run on my side with a highly shielded line. ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [April 5, 2003, 6:36pm UTC](https://boards.straightdope.com/t/can-a-street-light-really-disrupt-my-dsl-signal/166697/7 "2003-04-05T18:36:22Z")
There isn’t normally any shielding in telephone wiring. The twisted-pair configuration is very good at rejecting external signals. It’s just possible there is a pair mismatching in the wiring inside your building. Take the cover off the jack your DSL modem is connected to, and verify that the colored wires (red, green, yellow and black) are connected to the proper terminals (usually marked R, G, Y, and B). You are only concerned with the red/green pair if you have a single-line installation. If there’s a mismatch, it will have to be corrected at both the jack on the wall and at the entrance bridge for the telco connection into the building (usually a grey box on the outside wall where the drop line comes in from the pole). If you’re in an older building, the pairs may be color-code with stipes, instead. The first pair, for example will be brown-with-a-white-stripe and white-with-a-brown-stripe. If you have this type, it might be best to replace it with newer RGYB twisted pair, available at RadioShack among other places, since the older wiring tended to become untwisted during installation. ---
**Author:** ![NinetyWt](https://avatars.discourse-cdn.com/v4/letter/n/cc9497/32.png) [@NinetyWt](https://boards.straightdope.com/u/NinetyWt)\ **Post date:** [April 5, 2003, 7:18pm UTC](https://boards.straightdope.com/t/can-a-street-light-really-disrupt-my-dsl-signal/166697/8 "2003-04-05T19:18:36Z")
I wired this myself from the entrance bridge. I used one cable with all 4 pair to come from the bridge under the eave and into my office (sunroom). I am using a double outlet where I used red & green for one phone number and yellow & black for the other number. Wouldn’t this interference be enough to knock the phone out too? I am using a split DSL filter to have the phone and modem on-line at the same time. The phone works all night, no problem. ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [April 5, 2003, 7:42pm UTC](https://boards.straightdope.com/t/can-a-street-light-really-disrupt-my-dsl-signal/166697/9 "2003-04-05T19:42:07Z")
It might not necessarily knock out the phones. The DSL signal is much less tolerant of interference than the phone is. It sounds as though your internal wiring is just fine, so my guess is it’s something outside, but before jumping to conclusions, how far is your DSL modem from the jack? ---
**Author:** ![Spit](https://avatars.discourse-cdn.com/v4/letter/s/76d3ee/32.png) [@Spit](https://boards.straightdope.com/u/Spit)\ **Post date:** [April 5, 2003, 8:17pm UTC](https://boards.straightdope.com/t/can-a-street-light-really-disrupt-my-dsl-signal/166697/10 "2003-04-05T20:17:23Z")
Cool! I have the same problem! Every night around 6-7PM (Although I remarked last night that it was later than usual…possibly due to longer daylight hours) mine cuts out. Drives me nuts, because that is usually when I’m in the middle of a hot Civ 3 match. :mad: ---
**Author:** ![NinetyWt](https://avatars.discourse-cdn.com/v4/letter/n/cc9497/32.png) [@NinetyWt](https://boards.straightdope.com/u/NinetyWt)\ **Post date:** [April 5, 2003, 9:35pm UTC](https://boards.straightdope.com/t/can-a-street-light-really-disrupt-my-dsl-signal/166697/11 "2003-04-05T21:35:49Z")
The modem is at most a foot away from the jack. Lemme see can I make a diagram: Streetlight ``` 120 ft outside bridge 50 ft | inside jack _________________ | | splitter/filter # / \ 1 ft 12 ft / modem _______ / | 6 inches 900 mhz phone router / \ 5ft / \ 7 ft / \ computer Xbox (both ethernet) ``` **Spit** , it’s very annoying for me, as I like to work at night, and can’t get to engineering data over the 'net. My son is the one who has conniptions when he’s suddenly booted out of Ghost Recon live. ---
**Author:** ![NinetyWt](https://avatars.discourse-cdn.com/v4/letter/n/cc9497/32.png) [@NinetyWt](https://boards.straightdope.com/u/NinetyWt)\ **Post date:** [April 5, 2003, 9:37pm UTC](https://boards.straightdope.com/t/can-a-street-light-really-disrupt-my-dsl-signal/166697/12 "2003-04-05T21:37:22Z")
well I see the diagram went to ghit. Sorry about that. ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [April 5, 2003, 9:42pm UTC](https://boards.straightdope.com/t/can-a-street-light-really-disrupt-my-dsl-signal/166697/13 "2003-04-05T21:42:34Z")
if the modem is that close to the jack, you’ll want to use as short a piece of line cord to connect it as possible. Telephone line cord (the flat sort) does not have any shielding _or_ pair twisting, and can pick up interference pretty easily if it’s been kinked or crushed, and coiling it up can make it into a pretty good loop antenna. ---
**Author:** ![Spit](https://avatars.discourse-cdn.com/v4/letter/s/76d3ee/32.png) [@Spit](https://boards.straightdope.com/u/Spit)\ **Post date:** [April 5, 2003, 9:45pm UTC](https://boards.straightdope.com/t/can-a-street-light-really-disrupt-my-dsl-signal/166697/14 "2003-04-05T21:45:07Z")
I have Verizon with a Westell modem, and it will generally just kick off for a second, then begin flashing the ‘ready’ light. If I unplug it, and reconnect everything is jolly until the next night. Of course, I periodically get ‘hiccups’ where there is no obvious sign of trouble with the modem, but I can’t connect to any pages. As soon as I disconnect/reconnect, all is well. ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [April 5, 2003, 9:48pm UTC](https://boards.straightdope.com/t/can-a-street-light-really-disrupt-my-dsl-signal/166697/15 "2003-04-05T21:48:20Z")
I have Verizon DSL with the Westell WireSpeed modem too. But mine never cuts out. Ever. Needless to say, I’m happy with it. 😃 ---
**Author:** ![NinetyWt](https://avatars.discourse-cdn.com/v4/letter/n/cc9497/32.png) [@NinetyWt](https://boards.straightdope.com/u/NinetyWt)\ **Post date:** [April 5, 2003, 9:54pm UTC](https://boards.straightdope.com/t/can-a-street-light-really-disrupt-my-dsl-signal/166697/16 "2003-04-05T21:54:36Z")
**Spit** we’ve been around the world with the reboot thing. Sometimes I get a glimmer of hope, only to see it dashed. **Q!** I have some short short pieces of phone line that came with the DSL kit ~ they are probably only 4 inches or so ~ I will try that at once. Although, a fat round black cord was provided specifically for the modem ~ not your regular flat kind. Perhaps it’s shielded? Hopefully the short pieces are too; although they’re flat. The short piece is labeled: Y1 - HUA AWM 150 V 26AWG if that means anything. ---
**Author:** ![Spit](https://avatars.discourse-cdn.com/v4/letter/s/76d3ee/32.png) [@Spit](https://boards.straightdope.com/u/Spit)\ **Post date:** [April 5, 2003, 10:00pm UTC](https://boards.straightdope.com/t/can-a-street-light-really-disrupt-my-dsl-signal/166697/17 "2003-04-05T22:00:07Z")
Well, coming from dial-up for the past 6 years, I’m not complaing all that much. i just figured it was a quirk of DSL; but now that I see there may be a cause, I will see what I can do. (I do have the huge coil of phone line, which had made me wonder if perhaps it was acting as an antenna of some sort- used to have similar trouble with slow speeds on dial up due to a coiled cord) ---
**Author:** ![astro](https://avatars.discourse-cdn.com/v4/letter/a/9dc877/32.png) [@astro](https://boards.straightdope.com/u/astro)\ **Post date:** [April 5, 2003, 11:52pm UTC](https://boards.straightdope.com/t/can-a-street-light-really-disrupt-my-dsl-signal/166697/18 "2003-04-05T23:52:21Z")
The FCC has strict rules about allowable electro-magnetic radiation broadcasting output for hams and such. I don’t know if they govern street light power transformers. Maybe they could send an RF measuring van around. ---
**Author:** ![Spit](https://avatars.discourse-cdn.com/v4/letter/s/76d3ee/32.png) [@Spit](https://boards.straightdope.com/u/Spit)\ **Post date:** [April 6, 2003, 5:53am UTC](https://boards.straightdope.com/t/can-a-street-light-really-disrupt-my-dsl-signal/166697/19 "2003-04-06T05:53:00Z")
> [@](#): > > \*Originally posted by astro \* > \*\*The FCC has strict rules about allowable electro-magnetic radiation broadcasting output for hams and such. I don’t know if they govern street light power transformers. Maybe they could send an RF measuring van around. \*\* Actually, the restrictions are for power output- not interference. If you are getting a bad TV signal because of your buddy next door, then that is your tough cookie. (although most hams will try to fix the problem) Spit- KE4NGZ ---
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [April 6, 2003, 7:55am UTC](https://boards.straightdope.com/t/can-a-street-light-really-disrupt-my-dsl-signal/166697/20 "2003-04-06T07:55:19Z")
> [@](#): > > \*Originally posted by NinetyWt \* > \*\*My DSL goes out every night, around 6 pm. It’s back on in the a.m. I contacted BellSouth and the tech told me it could be the street light in front of my house. :dubious: > > Could this be true? Here’s what he said: > > I plan to watch tonite to see when the light comes on, but this seems like horsefeathers to me. \*\* It could be true, but it doesn’t matter. Call BellSouth back and point out that you are paying them for this DSL service, and it is their responsibility to deliver it to you. Whether it’s streetlight interference or whatever, that’s **their problem** , you just want the service you are paying for. You should not have to do their detective work for them to find out the problem, they have technicians whose job that is. You might use the “power of the customer”: ask them if this streetlight thing would still affect you if you switched to a cable modem service. But to be realistic, anything you can do to identify the details of the problem will help in getting it fixed. Like the various ideas people have posted here. And do try to make sure the problem is in their part of the wiring, outside your house. If it’s inside, in your wiring, they WILL charge you for a repair call. The way to check this is to disconnect everything else and connect your DSL modem to the wires right where it comes into your house. If the problem still happens, then it’s outside your house, and is definately their problem. [Next page](https://boards.straightdope.com/t/can-a-street-light-really-disrupt-my-dsl-signal/166697.md?page=2)