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sapling
join:2009-10-21
Cleveland, OH

sapling

Member

Is my line getting terrible AM radio interference? (Bitloading graph)

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I recently upgraded to a faster Uverse speed - 24mbps from 12mbps. Since the upgrade my router completely loses sync during the day. This starts right around sunrise and it reconnects right around sunset.

I downloaded UVRealtime in an attempt to figure out the problem. I noticed my Bitloading graph looks pretty awful compared to the ones I see here, so I started googling trying to figure out what it could be. I don't live next to an AM radio station so that seemed unlikely to me, but then I read something about how most stations lower their signal power significantly at night. Hmm. I finally decided to look up what stations were nearby in case I was surprised.

It turns out there are 5 stations within .5 - 1.0 miles of my place. Still, they weren't next door. How bad could it be? There must be thousands of people living with a mile of several AM stations in big cities.

Then I matched up the worst, chunkiest dips in my bitloading graph... and they seem to match up almost exactly. The interference looks far fatter and wider than what I saw called "AM interference" on any other bitloading graphs - a thin 2-3 pixel wide dip, hardly visible in some cases.

Is this some ridiculous coincidence? Surely not everyone living in a major city has interference this bad?

Attaching bitloading graph and a list of the radio stations (some stations are listed multiple times if they have different output signals at different times of the day.)

The 5 frequencies are: 790, 920, 970, 1190, 1690.

I also included the kilowatt power of the signal of each station, both at night and daytime, since I don't know relatively speaking what is powerful vs quite weak.

If this is the case, I know the upgrade didn't cause it - I'm assuming it just put me near enough the "edge" that the extra day interference knocks me offline. But I still can't believe the AM stations have that much impact compared to the other graphs I saw.

my thoughts

Anon

Yes, have seen large chucks from AM station(s), and while this may be a part of problem not sure it is the only problem.

Is this the same RG when on Max (12M) or different?
Was your original speed a self install? No reported issue on Max?

When large errors are seen by the RG, the RG reboots (reinit or retrain).
Suspect your original install was either self install (13M profile) or internet only tech install (19M) profile.
In both cases the radio station interference was already there, but your demand (profile) was low so your SN margin was acceptable. In current situation, to have 24M internet would need to be placed on 32M profile. This would dramatically lower your SN margin (strength of signal compared to surrounding noise, affected by increased loop length, increased noise, or increased demand...higher profile)

As lower output during evenings/nights less noise, increased power output from stations adds noise.

Now, I suspect, you have a bridge tap about 200-300 feet from RG, that is matching up with these frequencies, causing wider dips. Notice possible outline of dips at 3000-3600 (rises back at 3600), raking pattern at 5800 (5.8-6.2) 6200 and again at 7300-7600. If correct this is 5 dips should give 200 feet to 250 feet for bridge tap.

Recommended to call, chat for tech visit, program or call center rep should dispatch a Uverse tech.
Problem is probably beyond his responsibility, will need to run some tests at NID and serving terminal.
Once completed with need approval to create helper ticket for outside line tech to remove bridge tap.

While you did not post other pages from UVrealtime, do believe you have high error rates and low SN margin, based on bit graph guessing about 1400 feet, if could would like to see other pages.

Conclusion, need a tech visit, and most likely also a CIM (outside) tech visit.
sapling
join:2009-10-21
Cleveland, OH

sapling

Member

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This is the same RG as on 12M - it was an automatic upgrade with no tech visit.

It started as a self install, I guess? They came out and installed a brand new NID when I wasn't home, but didn't do anything past the NID. I used a crappy cord to wire from outside to inside, and it started causing disconnects within about a month. A tech came out to diagnose it and replaced it with a Cat5 that goes directly from the NID to the router. The distance is very short (maybe 6 feet), but the cable does have some extra loops - probably a 25 foot cable. I haven't moved / messed with it since he installed it and haven't had any major problems other than a random 2am disconnect here and there, and never lasted more than about 5 minutes. I always figured it was something to do with maintenance given the odd hour. Speed has always been fine when I tested it.

I actually have a tech coming in the morning but I'm not sure if inside or outside. The tier 1 support staff insisted it was a disconnected cable and wouldn't connect me to Tier 2. I've also posted in the Direct Help forums, in case the tech visit doesn't resolve it.

I also attached the main page and error page, hope it helps. I'm not sure what my actual distance is - it seems to fluctuate between 2200 and 2800.
sapling

sapling

Member

Also meant to add - it's interesting you mention a bridge tap - if I understand what they are correctly, it's just a long piece of cord that deadends some length away? In this case perhaps 200-300 feet?

That is pretty plausible - I live on a cul-de-sac, and the end of it with the last house is probably 200 or so feet away. So if they just strung the line all the way down there (or I guess someone down there had Uverse and disconnected it), that would make sense.
sapling

1 edit

sapling

Member

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So I was thinking of how to block radio signals... it occurred the router is sitting in a sort of window shelf right now (next to the air conditioner, but the air conditioner is off / unplugged).

I moved it down to the floor with a few feet of wall above it between it and the window, and it improved the profile a bit, to this. Looks like it may very well be radio, or at least something outside, if that small move has a visible impact?

However the overall profile is still bad - 115% bits in use and such. Distance 2800.

I also misgauged the amount of coiled cable in the window - probably no more than 6 feet wrapped up. The Cat 5 from the NID goes straight into a small jack with no excess, then the 6 feet of coiled phone cord goes from the jack to the router.

my thoughts

Anon

If your distance (loop length) is over 2200 feet, you should never have been placed on Max Turbo (24/3l) as best profile can support is 25M meaning fastest internet speed is Max Plus (18/1.5).

While I believe outside issue, also believe tech should lower profile and internet package.
For you this is a $10 per month savings.

Tech may also replace the RG, but I still would follow recommended listing that 32M profile, is a single pair install less than 2200 feet. 2200-3000 feet is single pair 25M profile and 3000 feet plus is bonded 25M profile.

Lowering profile will improve SN by about 4 (13.5 to 14.5) providing stable connection.
sapling
join:2009-10-21
Cleveland, OH

3 edits

sapling

Member

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I agree, and I'm fine with dropping to 18mbps - I actually tried to get the Tier 1 chat support to lower my speed to 18mbps, and my line profile to 25/2 to fix it. They complied... with the speed drop. Now my AT&T account reports I'm on Max Plus.

But they didn't update the line profile, sigh. So my internet stayed out the rest of the day and I didn't have the heart to get on chat with them a 4th time.

Overall my Uverse experience has been good, and I've had it for.. 6-7 years in different locations. But damn is their phone / chat tech support distressing to interact with if you have some sort of idea of the problem or how to fix it. Heck, I remember when my dry loop DSL went out years back and it took me 2 hours just to get someone on the phone who believed I had DSL without phone service / phone number.

I usually just humor tech support and do the unplug / reset routine for whatever device it is, because at the end of that they'll put you on with someone who can actually help you. Not so with AT&T! They'd actually rather send someone to your house than give you 5 minutes on a phone call with Tier 2. Absolutely blows my mind. If they'd just set my profile back to 25/2, I would have been happy and ignorant of all this radio interference and possible bridge taps.

Now I've found this damn graph and keep moving my router around to various locations trying to eke out a mild improvement. Case in point: I moved it around the corner into the bedroom on top of a shelf. No improvement that I can see from the last location on the floor...

I also thought it worth adding - I have dimmer lights all throughout the place which apparently give off interference too. Nothing I can do about it, I rent. I did turn them all off, but not sure if that helps or not. No major difference either way.

Edited to add - it's probably a good thing the tech is coming tomorrow. If I had a whole 'nother day with no internet and the knowledge it was AM radio waves blasting me into oblivion, I'd probably just end up breaking the router trying to pile random crap around it to protect it from radio waves....

...I also read a microwave works as a great Faraday cage... resisting the urge to try that... can't end well, router in a microwave... (For the record, the microwave would be unplugged, but I can already picture my horror when the tech gets here and I realized I forgot I left it in there.)
sapling

sapling

Member

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(Sorry I keep replying to myself... think of this is a journal dialoguing my tale of woe for some future soul trying to find out what's wrong with their internet.)

My internet just unexpectedly crapped out for a minute. I managed to capture the UV Realtime data since it didn't clear out this time. Looks like it absolutely exploded with FEC errors. No idea what happened, I didn't go near it and nothing changed in the room. Too early for radio stations to be transmitting and weather outside is clear. (For the record it's just sitting on the shelf - I didn't microwave it.)

The Bitloading graph didn't change visibly, so I'm not bothering to re-upload it.
sapling

sapling

Member

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Stats
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Errors
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Bitloading
Fixed! The tech fixed it!

I still have some of the weird AM radio interference, but he said I had a terrible connection out at the pole (a bad pair?) and was surprised I was connecting at all. It looks like I definitely qualify for 24 now!

He was literally here like 5 minutes. Awesome!
sapling

sapling

Member

Oh my god I posted that and not 5 minutes later lost connection. Checked router - flashing red "broadband" light just like before. I'm now back on my phone.

What, did the line fall off the pole?

I reset the router but it's just flashing red then green then red like before.

The tech literally JUST drove away!

Edit... Ok it now seems to be connected. I am ... Nervous.

my thoughts

Anon

Vastly improved, Max sync rate almost +20M, SN pproaching 15, and est. Loop length 1600, much closer to my original estimate of 1400.

Issue was loose or extended connection at terminal (pole)? How far is pole from RG, approaching 200 feet?

Tech probably running a test on outside line, that would cause RG to lose sync or went to cross box to check wiring.

Yes, now easily support 32M profile and 24 internet.
sapling
join:2009-10-21
Cleveland, OH

sapling

Member

Woohoo

Pole is... down the yard and across the street... I'm bad with distances, but maybe 150? So pretty close.

Thanks! And you're right I bet about the tech... he was still out there, I didn't even think of that.

brookeKrige
join:2012-11-05
San Jose, CA

brookeKrige

Member

If tech didn't say, but left a phone#, you can still call within few days to ask what his instruments reported for your outside line distance.