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Re: LF: Any ADSL2 BBand router / RF proof ?

To: <[email protected]>
Subject: Re: LF: Any ADSL2 BBand router / RF proof ?
From: "Graham" <[email protected]>
Date: Mon, 29 Nov 2010 01:37:38 -0000
Importance: Normal
In-reply-to: <008f01cb8f64$fb207120$4001a8c0@lark>
References: <[email protected]> <008f01cb8f64$fb207120$4001a8c0@lark>
Reply-to: [email protected]
Sender: [email protected]

UK.....and running down our best assets.

Not mention  selling the  family  jewels  , or in the  case of the
government .. polishing them ?

G..

--------------------------------------------------
From: "Alan Melia" <[email protected]>
Sent: Monday, November 29, 2010 1:29 AM
To: <[email protected]>
Subject: Re: LF: Any  ADSL2  BBand router / RF proof ?


Peter, you can blame the governments of the 1980s they would rather give
entertainment licences to silly little cable TV companies that all went bust
and were hoovered up by NTL for a song. BT offered to cable the UK with
fibre to the customers premises, if it was allowed to recover the investment with an entertainment licence, but all the vested interests cried foul. They
didnt want competition from BT. So when DSL came along it had to try an
build a data business on copper, using a "stone-age" technology. It doesnt
help being forced by the regulator to sell the whatever bandwith the
back-bedroom Telco want at less that cost....you (or BT subscribers) are
subsidising Virgin, AOL, and the rest. None of the so-called competition put
their own cables in, or built any exchanges, they just want cheap profits
from the assets, your assets, (the copper) already there. NTL hasnt made a
profit on its cable TV because of the competition from Sky. I am not
actually "out in the country", but I cant get an NTL/Virgin connection they
wont cable out here, not enough money in it. If you have to have cheap
internet connection, you get just what you pay for. Yet the Taxpayer is
paying 50% of every Railway season ticket cost.

To say that there is no expertise is rubbish....what do you think all the
trunk cables are? They are not copper. Anyway a lot of the cable
installation "expertise" is bought in. The real experience is required at
the ends and in commissioning. Pulling cable just needs muscle not brains.
Countries that had no infrastructure put fibre in straight away, and their
govenments were farsighted enough to see the benefits of subsidising it. Its
just another case of short-sighted short termism we are so good at in the
UK.....and running down our best assets.

Alan G3NYK

----- Original Message ----- From: "M0FMT" <[email protected]>
To: <[email protected]>
Sent: Monday, November 29, 2010 12:44 AM
Subject: Re: LF: Any ADSL2 BBand router / RF proof ?


Hi Ken

Thanks for the "teach in". Tell me why is BT so keen on copper wire it has
nothing but disadvantage.Open Reach must spend millions of pounds trying to
make it work. And now with these raids on the ducting because of the value
of copper it make even more sense to change over to fibre. However I am
being told it will never happen because on lack of expertise within BT.
These comments come from Open Reach at Liverpool. Have you any idea why they
don't import some engineering talent?

73 petefmt

I support www.NotSpotTelecom.Com your community Telco / ISP.

--- On Sun, 28/11/10, Ken <[email protected]> wrote:


From: Ken <[email protected]>
Subject: Re: LF: Any ADSL2 BBand router / RF proof ?
To: [email protected]
Date: Sunday, 28 November, 2010, 20:13





Hello Everyone.
I think you will find that with your line length from the serving exchange
(7km)? the S/N ratio will be poor, a minimum of 10dB is required, my copper
connection is about 2.7km which is considered to be approaching the limit,
although the tests at the customer NTE showed that 3Mbt/s.should have been
possible. At these line lengths any rf will swamp the DSL signal. I have
discussed this problem at length several time with the people I worked with at Adastral Park ( commonly known as BT Labs), both DSL and EMC, the problem
is compounded if a) you have a long length of overhead drop wire, b) the
number and configuration of any internal extensions, and c) the position of
the router with respect to the incomming NTE (master socket). If the
dropwire is long, the induced common mode interference will be transformed
into differential mode before it reaches the router, any internal extension
wiring will increase attenuation, especially if it is a 'star
configuration.
The router should be as close as possible to the incoming NTE. A spectral
analysis of my line revealed that there were no DSL carriers above 500kHz,
hence not being able to use 500kHz, if the router shuts down because a
corrupted incoming signal, it will start a 're-training' sequence with the
DSLAM in the serving exchange, however if either the line or the router is
changed, the exchange equipment will then go though a process of determining
the best possible data speed of the new configuration, thia can take up to
ten days, if during this time any of the speedtest sites are used different
data rates will be loged.

I changed my 1st generation BT Homehub router for an older BT Voyager 2500, which improved the situation with the HF bands but not at 500kHz, even with
high value common mode chokes on everything in sight. The problem was
finally solved by changing over to BT Infinity Fibre To The Cabinet (FTTC)
with copper line length of 400m giving data speeds of 14Mbt/s.

I hope some of this is both of use and interest you all.

73
Ken
M0KHW

----- Original Message ----- From: M0FMT
To: [email protected]
Sent: Friday, November 26, 2010 10:08 AM
Subject: Re: LF: Any ADSL2 BBand router / RF proof ?






Hi Again Graham and LF

Hmmmmm OK looks like you are in better shape than me. A local station who
has difficulty with his ADSL has put Ferrite clamp on filters on all leads
in and out of the Modem including the power supply lead. He claims (and I
have no reason to doubt him) that this has solved his problems. The modem is
the new BT Black Box one. I have one of those although much more reliable
and faster it still suffers from my description below. The issue I have
appears not to be Modem related but exchange based.

I talk to Larry regularly on 4m so next time, if I remember, I will get the
details of his solution Viz ferrite type and where on the lines he is
fitting them and forward it to you. It may help.
As before good luck with your efforts; what ever success you get please
publish it. Ken M0KHW Luton has an ADSL problem too so several people would
be interested I am sure.

73 es GL petefmt

I support www.NotSpotTelecom.Com your community Telco / ISP.

--- On Fri, 26/11/10, Graham <[email protected]> wrote:


From: Graham <[email protected]>
Subject: Re: LF: Any ADSL2 BBand router / RF proof ?
To: [email protected]
Date: Friday, 26 November, 2010, 0:49



Ok Pete

This is the new router , as its in the same place as the old one , with
(now) the same filters , the PC is linked with a short network cable , the
rest of the pc's are linked by radio. its the adsl like thats failing

The edimax router was quite robust , never had a drop out on HF and only
over 200 watts , feed , on 500 would stop the link , this one fails with 25
watts on 160 .. the router is off most of the day and night , only on with
the pc , the new router is faster , from 6 (old) meg to 9 med down and 500k
(old) to 890 k upload , but if it keeps dropping out with no cure then its
not much use for my usage

G,




From: M0FMT
Sent: Friday, November 26, 2010 12:26 AM
To: [email protected]
Subject: Re: LF: Any ADSL2 BBand router / RF proof ?











Hi Graham

Are you sure the problem is the router?

136, 500, 160 and to some extent 80m here are kill the ADSL. Even at very
low powers. If your ADSL is cut during your transmissions only and resumes
at the original speed directly afterwards it may well be the router being
temporarily being knocked out. If however you line stays down for a period
of time say several hours then it is not the router. What you are doing is
putting noise (owing to RF) onto your line which is being picked up at the
exchange DSLAM. The exchange equipment (DSLAM) serving your line will reduce
data speed to ensure that a connection of sorts is maintained. This speed
can go down to below 80kb/s from which it will not recover without technical
intervention by BT Open Reach. If it goes down to about 300/500kb/s it may
well recover it's original speed over a period of time BT quote 72 hours yes 72 hours (I think this time period is not a technical issue but one to stall
the punters off). On a good day the recovery period can be
speeded up by turning the router off and disconnecting every thing from the
line and waiting. This makes a quiet line for the automatic recovery to
work.... on a good day!!! If you don't have enough life left to wait for BT
to physically do some thing then the best thing is to write to BT HQ in
London to the their CEO (his name and location can be found with a bit of
research) and tell him what you think of his outfit. I know from experience he does not like receiving this kind of letter. You may have your ISP as Joe Blogs Internet Provider dot Com but in reality it is all provided by BT they own the final mile and the exchange ...... legal niceties to one side it is
a fact.
If you get a good Broad Band data rate of say 4/8mb/s your transmissions on
LF/MF will only slightly degrade your ADSL but if like me on the end of
7.5km of copper its only 1/1.5mb/s on a very good day, RF will wipe out your ADSL for a week or more. So without a lot of letter writing to BT and angry
phone calls your ASDL will not return to original speed..

To maintain a usable data rate on Broad Band here I can not use 136 or
500kc/s above a few Milli Watts at TX output about 1 Watt on 160m 80 about
50Watts and on 60m and above 100Watts (possibly more but not tested yet).
Also the longer you stay on the worst the speed degrades.My guess is with
ADSL2 having a much wider bandwidth the problem for Amateurs will extend
further up the spectrum than shown above.

Hope you are not in my situation....... Oh and don't believe all this Fibre stuff. Open Reach have told me that one reason why Fibre is not being rolled out like the Virgin setup is that there are only a few BT people capable of
working with Fibre. This is the reason why BT is Wedded to copper wire. So
we locally have Internet breakdowns owing to Junkies and the like ripping
the Copper cables out of BT ducting to pay for drugs... Bedfordshire has had
Internet disconnections for days owing to this phenomenon. So along with
cable theft and the lack of trained staff a proper interference free Broad
Band coverage using fibre in this country is looking particularly bleak.

Good luck!

73 es GL petefmt

I support www.NotSpotTelecom.Com your community Telco / ISP.

--- On Thu, 25/11/10, Graham <[email protected]> wrote:


From: Graham <[email protected]>
Subject: LF: Any ADSL2 BBand router / RF proof ?
To: [email protected]
Date: Thursday, 25 November, 2010, 22:06



Any ADSL2 BBand router / RF proof ?

Just upgraded to ADSL2 with a orange net-gear router/wifi router, now 15
watts on 160 kills the connection

router is in the same location as the old edimax , which kept running with
200 watts on 500 K and 400 on Hf

? any RF proof ADSL2 on the market >

Tnx - G..















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