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Guru
14,136 Views
Message 11 of 34

Re: Poor Broadband speed

A lot depends on the quality of them .....

 

I think the BT specification covers the issues ....

 

But a lot of the cheap and nasty ones don't.....and have the ability to affect broadband.

ib1703
Contributor
13,296 Views
Message 12 of 34

Re: Poor Broadband speed

 
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ib1703
Contributor
13,291 Views
Message 13 of 34

Re: Poor Broadband speed

My phone line is hissy. Tried master socket and no hiss. Changed ADSL microfilter and no hiss. Question - why do I get no hiss on the master socket without a micro filter but hiss on other sockets in the house uless working ADSL microfilter attached.

 

Regards

 

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Geoff93
Recognised Expert
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Message 14 of 34

Re: Poor Broadband speed

You need a filter on every socket that you plug a phone into to separate the broadband signal from the phone one.  Some also suggest that you put a filter on every socket regardless.

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Sephiroth
Contributor
13,245 Views
Message 15 of 34

Re: Poor Broadband speed

AN expert I know suggests that you remove the modem when you perform the hiss test.  If the noise goes, then the modem is introducing the noise.

 

He reasons that if the phone operates in the 300 - 3400 Hz range, and the filter separates this from BB, then if all your filters are working OK or not on the circuit, then any hiss noise you hear is in the BB range.

 

Hope that Helps.

Seph

My advice is at your risk.
ib1703
Contributor
13,221 Views
Message 16 of 34

Re: Poor Broadband speed

After further checking the noise/hiss I can hear without the micro filter is indeed the modem (turned it off to check). The hiss I could hear with microfilter attached would appear to have been down to a faulty microfilter.

 

Thanks

 

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PheeragHfre
Recognised Expert
13,140 Views
Message 17 of 34

Re: Poor Broadband speed

 

A little more info for reference.

 

The Line Noise test is a good indicator of overall Telephone Line condition but for ADSL2+ in particular there are many other non audible factors to consider as mentioned before by RogerB.

 

Any transmission noise entering the alloted ADSL2+ frequencies will degrade the signal or even disconnect your the router.

 

Good Cabling/screening for all systems TV/Audio/PC/Router etc not forgetting reasonable isolation from mains interference & those ubiquitous Mobile Devices & remote telephones (transient signals from domestic radio frequencies devices can be hard to pin down. Smiley Indifferent) may well save you time & extra expense if done properly.

 

http://en.wikipedia.org/wiki/ITU_G.992.3/4

http://en.wikipedia.org/wiki/File:ADSL2_frequencies.png

http://en.wikipedia.org/wiki/File_talk:ADSL2_frequencies.png

 

Info like this can help but watch out for the gotchas that don't apply to your situation or location.

http://www.dslreports.com/forum/r24854974-Other-adsl2-line-interference-and-tone-attenuation

 

 

 

"I have this awful feeling someone is watching every move I make (one of my pet hates is router location tagging)." Marvin (A paranoid Android)
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phobos515
Beginner
12,610 Views
Message 18 of 34

Re: Poor Broadband speed

Roger, it's not really about the quality, since all power line network 'adapters' work the same way: by injecting wide band radio frequency energy into the household wiring. The household wiring simply isn't designed to carry high frequency signals. It's not balanced, and the result is predictable: the mains wiring acts as an antenna/aerial, radiating the wideband signals some considerable distance, interfering with radio reception across the range of frequencies they use.

 

The 'new' BT Comtrend devices are possibly much worse, since they radiate right up into the VHF range, covering the broadcast FM band as well as DAB frequencies. On the lower radio frequencies (used by adsl) the chance of coupling between the telephone and household wiring is very high, and many users have found their ADSL disconnecting or at least lowering throughput significantly.

 

The older Contrend ones blanketed the short wave radio spectrum with a screeching noise. The short wave range includes international broadcasters, ship/shore radio, aeronautical communications, radio hams and so on and Ofcom have been, as expected, receiving a pile of complaints. BT, to their credit, have been hardwiring their installations with cat3 cable when Ofcom refer the complaint to them.

 

Your neighbour may be using power line adapters bought over the counter at his local PC shop, and innocently lowering ADSL lines speeds for people in the vicinity.

 

The potentially interfering emissions from pwer line network devices is over 1000(!) times  legally permissable levels. They got on the market by the makers self-certifying their own products and bunging a CE sticker on them, and now we're reaping the harvest.

 

All in all, power line network adapters are a very poor choice for anyone, more so for a ADSL user..

Sephiroth
Contributor
12,598 Views
Message 19 of 34

Re: Poor Broadband speed


@phobos515 wrote:

....... 

All in all, power line network adapters are a very poor choice for anyone, more so for a ADSL user..


Notwithstanding your explanation of RF propagation on mains wiring, I think it's an unjustifiable leap for you to have siad what is highlighted above.

 

What is a "very poor choice" in my case?  I have 3 powerline adaptors on two floors and I get the full 50/5 downstream/upstream speed from my VM cable connection; likewise 38/8 on my BT Infinity connection.

 

No way is that a poor choice, especially as there is no other sensible solution for house topologies such as mine.

Seph

My advice is at your risk.
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phobos515
Beginner
12,589 Views
Message 20 of 34

Re: Poor Broadband speed

Maybe I should have said "they're a poor choice for anyone who cares about the effects their actions might have on others". They will cause interference to radio every time they're used in the vicinity of one that tunes over the frequencies they radiate over, and they are known to knock down ADSL speeds by coupling interfering signals to the phone lines/household cabling. There's a legal challenge up and coming too. Wired connections are always the best choice. Okay, so some people don't want to run a wire from one room to another, but it's well worth it in terms of speed, neighbour friendliness and economy. A cable doesn't take constant mains power or tie up a socket, and it doesn't couple noise to the phone line or interfere with radios. Cheaper, too. After all, with powerline adapters you need a cat cable AND a powerline adapter for each PC you want to link, when you could just make the connection with one cat cable. And houses where wifi doesn't work are really few and far between.

 

The reason I came to this thread, though, was because I have the same problem as the original poster: IP profile down to 128Kb/s from its usual 5.75 mb/s, and download speeds averaging 40-68 kb/s 😞 Quite a drop. I have to agree with what someone above said: the support for this problem is pretty poor. It really should be possible to get it reset quickly, if, for instance, you've had power outages causing disconnects, wrongly interpreted as poor line quality by the servers. After negotiating the call centre obstacles, I now have to wait until next Tuesday for the engineer, then no doubt another delay while the profile is reset. I don't suppose I'll get a refund on my bill for a week or so with little better than dialup speeds. Smiley Sad

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