Plasma tv interfering with ADSL2+

This week my connection was upgraded from adsl 8 meg to adsl2+ 20 meg. Since the upgrade whenever I have my Panasonic plasma tv on and adsl throughput drops to effectively nothing although the router stays synced. I've tried moving the router to the master socket but it didn't have any effect. Has anyone got any ideas how I can stop this happening?

Do you know any amateur radio enthusiasts in your area? This is a known issue with HAM radio (in the 2-30MHz bands). Its also suspected of being a problem with ADSL.

If you don't know any HAMs, there is probably a club near you.. contact them for advice on EMC (they will understand). BUT, be careful... ..

Cure? Its complicated....

Firstly, fit RF chokes on the TV power lead, and quite possibly the RF/sat lead. A choke need be as simple as an iron 'ring' which you can wind the mains cable around (obviously need to remove the plug then refit it, depending on the power lead interface). OR, you might be able to find a snap-on choke- it looks like a rectangular which opens lengthways, you put the cable in and fold the open half over.

If this doesn't make any difference, then it is the TV itself which is radiating, and you need to contact the manufacturer. NOT the retailer, but the manufacturer. And OFCOM. The manufacturuer, as it is there responsibility to ensure that their equipment meets EU EMC/EMR regulations (CISPR22, and EN55022:2006). OFCOM, to raise awareness of the EMC issue (but make it plain that you do not want them to investigate - that costs £50 unless you know 'how' to get it done for free!).

The caveat about HAMS: This is NOT mean to be disrespectful in anyway, but some HAMS have a real bee about plasma (the Mar 2011 issue of RADCOM has the 'results' of a survey on Plasma interference on ham radio) - many believe that plasma TV should be withdrawn from the market, and applaud manufacturers who instead of fixing the problem replace the set with an inferior LCD/LED model. Drop me a PM if needed and I'll get a copy to you. The 'conclusions' are interesting...

Out of interest, what model Panny is it? I have the P42G20B, and have suffered no issues.

More than happy to help you work this out - DONT BIN THE PLASMA!

I don't know of any Hams around here. I was routing through my drawer earlier and found this

http://www.zen16617.zen.co.uk/photo.JPG

I clipped it onto the power cable on the tv (there's also a block moulded onto the cable already) but it had no effect. The tv is a Panasonic TH42PZ80.

How close is the router to the TV?

Do they share the same power socket?

They do normally. But when I was investigating I moved the router across the other side of the house on totally different power and phone sockets to no effect

In reply to a post by No_One:

They do normally. But when I was investigating I moved the router across the other side of the house on totally different power and phone sockets to no effect

Is the PC on a wired or wireless connection?

We've got 2 desktops, 2 laptops and 2 iphones. When the tv is on they all fail to load anything despite showing a full wifi signal. All this has started since the migration to ADSL2+ yesterday.

Although the tv is 2 1/2 years old, it came with a 5 year manufacturer warranty. I guess this should be grounds for a warranty claim

In reply to a post by No_One:

This week my connection was upgraded from adsl 8 meg to adsl2+ 20 meg. Since the upgrade whenever I have my Panasonic plasma tv on and adsl throughput drops to effectively nothing although the router stays synced. I've tried moving the router to the master socket but it didn't have any effect. Has anyone got any ideas how I can stop this happening?

It also maybe having a detrimental effect on your neighbours adsl too, are you connecting using wireless or by Ethernet cable to your router? set up a think broadband quality meter and enable ping responses from your router, it will be interesting to see if there is lots of packet loss when this plasma tv is switched on,

You could stop using the tv ,sell it buy one that doesn't cause issues, or locate the tv away from the telphone line /extensions &router, or build a faraday cage and put the plasma in there to isolate it's radiation

Edited by tommy45 (Sat 09-Jul-11 15:49:32)

In reply to a post by No_One:

We've got 2 desktops, 2 laptops and 2 iphones. When the tv is on they all fail to load anything despite showing a full wifi signal. All this has started since the migration to ADSL2+ yesterday.

Are they all wifi then? If so try a wired connection, see if that's ok with the TV on.

In reply to a post by tommy45:

set up a think broadband quality meter and enable ping responses from your router, it will be interesting to see if there is lots of packet loss when this plasma tv is switched on,

Any idea how you enable ping response on a Netgear DG834G?

In reply to a post by No_One:

In reply to a post by tommy45:

set up a think broadband quality meter and enable ping responses from your router, it will be interesting to see if there is lots of packet loss when this plasma tv is switched on,

Any idea how you enable ping response on a Netgear DG834G?

on mine it's in wan setup select "respond to ping on wan port "but i use dgteam firmware so menus maybe a little different failing that you can also ping your 1st hop after the router,using something like win mtr which is free, or pingplotter the pro is only a 30day trial, unless you want to buy it, or you have the ping command built into windows but with ping plotter it is easier to change the packet size and it gives some other related info too

Edited by tommy45 (Sat 09-Jul-11 16:17:29)

Thanks. got it all set up now. Not sure how I'm going to convince Panasonic that this is a fault etc

Here's the monitor. The loss at the start is when I had ping response turned off so ignore that

Edited by No_One (Sat 09-Jul-11 16:17:38)

In reply to a post by No_One:

Thanks. got it all set up now. Not sure how I'm going to convince Panasonic that this is a fault etc

Here's the monitor. The loss at the start is when I had ping response turned off so ignore that

thing is it's not an actual fault with the tv set itself, but a case of it possibly exceeding the allowed levels of electromagnetic interference when used ,most things are supposed to conform to a certain standard and it's the responsibility of the manufacturer to ensure that the equipment meets this , if it doesn't presumably they can be fined i don't know much on the in's & out's of the legislation,
IMO bt should be given powers to suspend disconnect customers who are responsible for the injection of emi into its telephony network when it has an impact on others nearby , if they fail to stop it happening after bt sfi have identified such and given the offending customer notice

It already works similar to this with the electricity companies , example if a buisness installs equipment that causes interference or disruption of power to others they will issue a notice that they fix the problem or stop use of the equipment that is causing it, if they refuse or fail to do this then they get disconnected simples, why should bet be any different

Edited by tommy45 (Sat 09-Jul-11 16:30:45)

In reply to a post by tommy45:

In reply to a post by No_One:

Thanks. got it all set up now. Not sure how I'm going to convince Panasonic that this is a fault etc

Here's the monitor. The loss at the start is when I had ping response turned off so ignore that

thing is it's not an actual fault with the tv set itself, but a case of it possibly exceeding the allowed levels of electromagnetic interference when used ,most things are supposed to conform to a certain standard and it's the responsibility of the manufacturer to ensure that the equipment meets this , if it doesn't presumably they can be fined i don't know much on the in's & out's of the legislation,
IMO bt should be given powers to suspend disconnect customers who are responsible for the injection of emi into its telephony network when it has an impact on others nearby , if they fail to stop it happening after bt sfi have identified such and given the offending customer notice

Why do I see myself having to sell this tv?

It also maybe having a detrimental effect on your neighbours adsl too

My neighbour has his Samsung TV close to his phone line. When he switches it on my noise margin drops from about 18db to 6db. So I get a permanent slow connection.

You could try using screened extension cable if you have any internal telephone extensions adsl nation i think sell it, just that some diy extension cable is naff it has to be twisted pair at least to block out any interference , as for connecting via wireless, if it's killing that there isn't really much that can be done about that apart from use wired only , modern day tech, you would think the more advanced it becomes the less unwanted side effects would occur , but it seems to be the opposite, the other thing that is said to kill your adsl signal is those powerline devices apparently they even can cause interference with aviation

Nah, the wifi side of things is fine. When the tv is on I can still log into the the wifi and load up the router configuration page. It's the ADSL side it's messing up. Could the tv be outputting within the specs, but the old router has insufficient shielding?

Is the phone line near the TV?

How short is the router phone cable?

The router connects to an extension about 2 feet from the tv. But when I connected the router into the master socket and turned the tv on, the effect was the same

In reply to a post by tehidyman:

It also maybe having a detrimental effect on your neighbours adsl too

My neighbour has his Samsung TV close to his phone line. When he switches it on my noise margin drops from about 18db to 6db. So I get a permanent slow connection.

Down my street there are lots of businesses mainly small shops, my connection since being ADSL2+ has suffered issues fluctuation in downstream SNR increased attenuation,also the odd disconnect too and packet loss and high error rates during the time it's affected, in the past the packet loss issues crippled my downstream throughput , more recently i have a new issue packet loss upto 40% at times , but things are mostly unaffected in that i can still download at max speed but only if i use more than a single stream(during periods of packet loss) and once i start downloading the loss stops dead the same happened it i upload too,
The most noticeable effect it has is watching i player HD is fine,where as normal will occasionally break up, causing the sound to repeat with a 2 second delay,lol

Edited by tommy45 (Sat 09-Jul-11 16:56:15)

Can you try a different router?

haven't got another one here. Going to ask around and see if I can borrow one

Failing that try the tv in a different room switched on for testing purposes, the furthest away from the telephone socket incoming cable and router , see if it
1 stops causing issues confirm by checking (tbbqm )
2 or is less severe than it was before you moved it
If either of those observed then maybe having the tv in that room all the time or moving the bt master socket and router into that room, and running a Ethernet cable under the floor in to the room with tv in or just use wireless maybe are viable option's to you

get some tin foil and put it around a box. Put your router in it and connect the router to the test socket behind the master socket. Plug your pc directly into that. What happens then?

http://www.thinkbroadband.com/ping/share/55a0bc231cf...

you can clearly see the effect turning the tv on did there

does the tv also interfere with [am/mw] radio stations?

It doesn't appear to, no

Contract
Regarding your Plasma TV, legally you must first approach the SUPPLIER, not the Manufacturer, for a solution.

Legally, your Contract is with the Supplier - who may ask you to co-operate with the Manufacturer - but keep careful records of all correspondence and contacts.

You may also wish to notify and copy to Trading Standards.
If bought by Credit Card and more than £100 was involved on that Card, you should also notify the Credit Card Card company and keep it updated on progress or otherwise.


Testing
As well as the various Tests suggested by others, I would recommend-

1) With the TV OFF and Unplugged, Switch the Router OFF and note the results including any signal levels showing on your various devices

2) Switch the TV ON; and again note the signal levels showing on your various devices

3) Leaving the TV ON, Switch the Router ON; and note the signal levels

4) Switch OFF and Unplug the TV, keeping the Router ON, noting the signal levels etc.

During 3 & 4 you should also try making connection with at least some of the devices, at least one cabled directly to the Router and one using WiFi.

Additionally, you should try those tests with the TV in Standby Mode as well as fully ON. Most recent TVs have Switching Mode Power Supplies internally; and the problems may be arising there rather than in the Plasma Screen.

From experience of doing similar cross-checks on other devices, you may wish to make out a Test Plan, to ensure that you do not forget or confuse some of the steps.

Record the results on that Test Plan; and copy it to to the various parties.

I had the exact same issue, my Samsung plasma TV took out my ADSL2+ when it was turned on, CRC errors mounted up into the millions and noise margin dropped off massively.

No amount of tin foil or moving of the router fixed this, I had to sell the TV and get an LCD TV which doesn't affect the connection what so ever.

I think manufactures really don't give a [censored] what they make or how their products affect or services.

Just read this thread. It sounds like this might be common with Plasma tv's. I got a 50inch LG plasma and it causes my noise margin to drop by about 2 or 3 db. Altho it doesn't seem to affect my connection much. Unless i sync when the tv is on then il sync slower than normal. But if it syncs at its usual 8.2mbit or so with the tv off when the tv is on after that it doesn't make it disconnect or do anything bad.

Also and this is curious i never noticed my noise margin dropping or being affected at all by the plasma before i upgraded to adsl2 llu

ADSL2+ uses additional higher frequencies as compared to standard ADSL. Perhaps it is these additional frequencies with which the plasma is interfering.

That's what I'm thinking is most likely. I'm going to ask around and see if I can borrow another router from a friend just as a process of elimination. If not I'll try contacting Panasonic (although the set is 2 1/2 years old, it came with a 5 year manufacturer warranty). If I don't have any luck there I might have to just sell it and buy a new set.

We have Panasonic plasma. The TV came with 2 of those iron chokes which the manual states must be put around the LAN cable on both ends.

I am unable to tell if our TV is creating any problems due to not being able to see the router stats on infinity.

I guess your tv has internet connectivity then. mine doesn't

In reply to a post by No_One:

I guess your tv has internet connectivity then. mine doesn't

mine doesn't either and it still affects the router. I dont think this is anything todo with a plasma using the internet. It's somekind of interference they give off and from this thread it sounds like they all do it prolly some worse than others. IF you do end up selling your plasma it might be a wise choice to get a lcd tv as they dont seem to have this issue.

Just a comment (and I know this isn't hugely helpful) but I have had three different plasma TVs over the last 8 years - two of them Panasonic - and none of them have ever affected my ADSL.

My plasma is 2 1/2 years old but this problem only started when I upgraded to ADSL2+ which if far more susceptible to interference than ADSL is. I've just submitted an order to revert back to ADSL 8 meg. Once that's gone through I hope everything returns to normal

This is an interesting thread. Amateur radio operators have been aware of interference to their shortwave radios from plasma sets for many years, and Panasonic seem to be the worst offenders. Interference normally occurs over the whole HF range, 2MHz to 28MHz, and is apparently radiated directly from the plasma display itself rather than up cables - this passes EU EMC tests as they only do conducted emissions below 30MHz.

This is the first time I have seen this problem affecting ADSL. Apart from doing obvious things like keeping your broadband cabling away from your TV, the way forward is via Panasonic, who have been quite helpful in amateur cases. Or even better, ditch that plasma and invest in an LCD...

I had exactly this issue when my line got upgraded to ADSL2+. Previously I had no problems on ADSL Max with a rock solid 8meg sync.

Have you tried removing the ring wire on the master and all extension sockets?

I had an extension socket (with the sky box plugged in to it) within a couple of feet of my 50" plasma (router was plugged in to master socket at other end of room) and the ring wire was acting as a giant aerial and feeding the RF interference back to the master socket.

When I removed the ring wire, my sync went from 8meg to 15meg and the CRC errors etc dropped back to virtually nothing and I have not had any problems since.

I also fitted an ADSL Nation faceplate and RF Choke to the plasma power lead just to be doubly sure.

Hope this helps.

Tony

Edit: replied to wrong poster, should have been to No_One.

Edited by toaster1971 (Mon 11-Jul-11 14:10:32)

Post deleted by ChrisWilson

Edited by deleted (Mon 19-Aug-13 15:25:23)

Do you realise this thread is 2 years old?

That is almost a spam post.

There's no way the filter can work as the DSL connection is unfiltered - only the phone connection is filtered.
Looks like it was designed by someone with too much time on their hands.

That is almost a spam post.

Yep, that had crossed my mind too.

Actually he is filtering out in the ADSL2+ frequency bands, as he says not for user with ADSL2+ or more accurately ADSL2+ where there is any usable signal above 1 MHz as his filter will be removing it.

Bookmarked as an example of how radio hams can interfere with ADSL services