Hi all

Thanks to all respondents on my earlier home networking thread.
Just one or two more points if I may....

Thoughts a

Fit Clarity Adaptor #16134 at master box.
As I have 2 cables run to loft already, use one cable to take 2, 3 and 5
upto loft and connect to existing distribution juntion box for telephones.
Use separate cable to take A and B to loft.

Is there an "ADSL only" connection box available that I can terminate A and
B in (in the loft) for the router/modem - RJ11?

Is the base plate for the master box different between analogue and ADSL?
From the web picture of the #16134 it appears to have a similar male part to
plug into the base plate.

TIA

Phil

TheScullster wrote:

Fit Clarity Adaptor #16134 at master box.
As I have 2 cables run to loft already, use one cable to take 2, 3 and 5
upto loft and connect to existing distribution juntion box for telephones.
Use separate cable to take A and B to loft.

sounds ok

Is there an "ADSL only" connection box available that I can terminate A and
B in (in the loft) for the router/modem - RJ11?

use any RJ11 or RJ45 faceplate

Is the base plate for the master box different between analogue and ADSL?
From the web picture of the #16134 it appears to have a similar male part to
plug into the base plate.

No the actual NTE part of it remains the same, just the faceplate changes.

On Thu, 18 Jan 2007 13:50:33 -0000 someone who may be "TheScullster"
wrote this:-

As I have 2 cables run to loft already,

Something you didn't bother to tell us earlier, when you gave the
strong impression that there is only one cable.

Is there an "ADSL only" connection box available that I can terminate A and
B in (in the loft) for the router/modem - RJ11?

You can use an RJ11 or RJ45 socket. The lead will be an RJ11, but
this will plug into an RJ45. See the bottom of
http://www.clarity.it/xcart/home.php?cat=259

Is the base plate for the master box different between analogue and ADSL?

What you do is unscrew the existing bottom bit at the front and put
the new one http://www.clarity.it/xcart/home.php?cat=262 in. If you
have an older NTE5 get the screws for 20p and you won't knacker the
threads, so you can put the old bottom bit back should you want.

The new bit sticks out a little and so may not find favour with the
domestic authorities. Tell her that it is a lot neater looking than
dangly filters everywhere.




--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

"Andy Burns" wrote

Is there an "ADSL only" connection box available that I can terminate A
and B in (in the loft) for the router/modem - RJ11?

use any RJ11 or RJ45 faceplate


How do you know which connections to make off the A & B feeds to with these
modules?
I have fitted the RJ45s for the wired network, but ISTR these were just
colour coded for network wiring colours!

Phil

TheScullster wrote:

How do you know which connections to make off the A & B feeds to with these
modules?

B leg should be -48v, but I don't suppose it matters really, even for
most phones they doesn't care, you can get polarity reversals with
caller ID anyway, and when you've passed through a microfilter it should
chop off DC up to 3KHz or so, as the ADSL signal is above that frequency.

I have fitted the RJ45s for the wired network, but ISTR these were just
colour coded for network wiring colours!

Colours depend if you're using EIA 568A or 568B, so long as you use the
same each end you should be OK, unless you using gigabit (or the
uncommon 100 base-TX) you only need 1/3 and 2/6 pairs anyway.

"David Hansen" wrote


What you do is unscrew the existing bottom bit at the front and put
the new one http://www.clarity.it/xcart/home.php?cat=262 in. If you
have an older NTE5 get the screws for 20p and you won't knacker the
threads, so you can put the old bottom bit back should you want.


Presumably I can only fit the new face plate once the service has been
swapped to ADSL?

The new bit sticks out a little and so may not find favour with the
domestic authorities.

As the phone point is just inside the front door, this is not good news

Thanks Dave

Phil

On Thu, 18 Jan 2007 15:54:05 -0000 someone who may be "TheScullster"
wrote this:-

Presumably I can only fit the new face plate once the service has been
swapped to ADSL?

No. In fact you should fit it before ADSL is turned on, do all the
other wiring and set everything ready to go.

As a bonus, if you do this you may find that ADSL is turned on a day
or so before the date you are given.



--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

On Thu, 18 Jan 2007 15:03:41 -0000 someone who may be "TheScullster"
wrote this:-

How do you know which connections to make off the A & B feeds to with these
modules?

http://www.clarity.it/xcart/product....cat=259&page=1
explains for one type of socket. You should be able to work it out
for the other type of socket, but the instructions that come with
http://www.clarity.it/xcart/product....cat=262&page=1
explain it all as well.

I have fitted the RJ45s for the wired network, but ISTR these were just
colour coded for network wiring colours!

A search engine will soon pull up the pin numbers that go with the
colours for this sort of wiring.



--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

TheScullster wrote:

Presumably I can only fit the new face plate once the service has been
swapped to ADSL?

No, it's fine to connect it all up in advance.

"Andy Burns" wrote


No, it's fine to connect it all up in advance.

But will the standard telephone extension wiring still operate, provided I
connect to 2, 3 and 5 of the new ADSL faceplate even with the old non-ADSL
service still running?

Phil

TheScullster wrote:

But will the standard telephone extension wiring still operate, provided I
connect to 2, 3 and 5 of the new ADSL faceplate even with the old non-ADSL
service still running?

yep, the filter lets through signals from the incoming pair within the
normal phone frequency range to your phone wiring, until you have ADSL
service that's all that will be on the line anyway.

An unfiltered signal direct from the A/B legs goes to the router, it
internally filters out the bits it's not interested in. I realise this
is slightly at odds with what I said earlier, the DC-3KHz signal is
what is allowed through to the phone side, rather than what is blocked
from the ADSL side.

"Andy Burns" wrote


yep, the filter lets through signals from the incoming pair within the
normal phone frequency range to your phone wiring, until you have ADSL
service that's all that will be on the line anyway.


Thanks Andy and Dave that's brilliant.
Like to know exactly where I'm going before I set off IYSWIM.

Phil

TheScullster wrote:
Hi all

Thanks to all respondents on my earlier home networking thread.
Just one or two more points if I may....

Thoughts a

Fit Clarity Adaptor #16134 at master box.

Would also recommend fitting an in-line surge protector also from
Clarity

http://www.clarity.it/acatalog/surge_protectors.html

Should be fitted as near as possible to the incoming ADSL filter..

I once lost all our phones which are daisy chained (like you describe
yours are) plus a PC modem in a lightning storm. cheap (£13.98) for
the protection it offers.

In article . com,
"ironer" writes:

Would also recommend fitting an in-line surge protector also from
Clarity

http://www.clarity.it/acatalog/surge_protectors.html

Should be fitted as near as possible to the incoming ADSL filter..

I once lost all our phones which are daisy chained (like you describe
yours are) plus a PC modem in a lightning storm. cheap (=A313.98) for
the protection it offers.

This type of surge protector is completely useless for protecting
equipment which is connected to anything else against lightning.
You need common mode protection, which will have a grounding
connection point on the surge protector.

--
Andrew Gabriel

Andy Burns wrote:
TheScullster wrote:

But will the standard telephone extension wiring still operate,
provided I connect to 2, 3 and 5 of the new ADSL faceplate even with
the old non-ADSL service still running?

yep, the filter lets through signals from the incoming pair within the
normal phone frequency range to your phone wiring, until you have ADSL
service that's all that will be on the line anyway.

An unfiltered signal direct from the A/B legs goes to the router, it
internally filters out the bits it's not interested in. I realise this
is slightly at odds with what I said earlier, the DC-3KHz signal is
what is allowed through to the phone side, rather than what is blocked
from the ADSL side.

IIRC its more that the filters stops the phone injecting anything above
wherever broadband starts..10Khz or so?

The exchange already will have filtered out any HF on incoming phones..

In article ,
The Natural Philosopher writes:
Andy Burns wrote:
TheScullster wrote:

But will the standard telephone extension wiring still operate,
provided I connect to 2, 3 and 5 of the new ADSL faceplate even with
the old non-ADSL service still running?

yep, the filter lets through signals from the incoming pair within the
normal phone frequency range to your phone wiring, until you have ADSL
service that's all that will be on the line anyway.

An unfiltered signal direct from the A/B legs goes to the router, it
internally filters out the bits it's not interested in. I realise this
is slightly at odds with what I said earlier, the DC-3KHz signal is
what is allowed through to the phone side, rather than what is blocked
from the ADSL side.

IIRC its more that the filters stops the phone injecting anything above
wherever broadband starts..10Khz or so?

Actually, it's so the phone doesn't attenuate the higher frequency
broadband data.

The exchange already will have filtered out any HF on incoming phones..

--
Andrew Gabriel

Andrew Gabriel wrote:
In article . com,
"ironer" writes:

Would also recommend fitting an in-line surge protector also from
Clarity

http://www.clarity.it/acatalog/surge_protectors.html

//snip//

This type of surge protector is completely useless for protecting
equipment which is connected to anything else against lightning.
You need common mode protection, which will have a grounding
connection point on the surge protector.


Interesting...It would be highly useful to know what protection (or
specific pretective device) you would recommend for the type of
separated ADSL/PSTN home network discussed in this thread. How should
the protected circuit be configured?

For the reasons given, IMHE some protection is absolutely essential.

Are you saying that it is the connection to the PC & router which makes
the Clarity device is ineffective? Not entirely sure that I follow
why. What circuit arrangements will the Clarity device protect?

The only information I have is the very brief description on the
Clarity website, but the device appears to be a gas discharge tube
which shorts the incoming telephone line on oevr-voltage. So long as
there isn't a parallel fault on the local power supply and the local
ground plane potential stays unaffected, why isn't that enough?

ironer wrote:
Interesting...It would be highly useful to know what protection (or
specific pretective device) you would recommend for the type of
separated ADSL/PSTN home network discussed in this thread. How should
the protected circuit be configured?

Clarity makes a connection between two wires. Let's say a surge is
'pushed' down A wire while B wire 'sucks' that surge. Therefore a Gas
Discharge Tube (GDT) shunts that surge from A to B; does not pass
through modem.

However that is not the type of surge that typically does damage.
Destructive surges, that seek earth ground, 'push' down both A and B
wires. Now that surge is on both sides of the GDT. GDT sees no
voltage (shunts nothing) as the surge continues down both wires,
through modem, and into earth. Protector sees no surge as modem is
destroyed by that surge. Andrew describes it:
common mode protection, which will have a grounding
connection point on the surge protector.

In North America, these earthed 'whole house' protectors are
installed, for free, on every subscriber line where it enters a
building. Protectors don't stop or absorb what 4 kilometers of sky
could not. Protectors shunt (clamp, connect, divert) that surge to
earth. A surge earthed where it enters a building will not overwhelm
protection already inside the modem.

This is also how BT does it. Their $multi-million computer connects
to overhead wires everywhere in town. Does BT shutdown phone service
for every thunderstorm? Do operators remove headsets so as to not be
shocked by lightning? Of course not. BT even before WWII was earthing
every wire that entered the facility. A surge that is connected to
earth will not go farther inside a building to overwhelm protection at
computer or operator.

Clarity device does not do this. The Clarity device is not designed
to earth common mode transients. How do you know? Where is the less
than 3 meter dedicated connection to earthing?

Some telephone line protectors:
http://www.one.co.uk/catalogue/teleb...otect/22PX.HTM
http://www.keison.co.uk/furse/furse11.htm
http://www.citelprotection.com/engli..._B380_B480.PDF
http://www.oneac.com/pdf/917116c.pdf
http://www.digitaltele.com/edco.htm

Unfortunately, some of these POTS (Plain Old Telephone Sevice)
devices may have too much capacitance for RF frequencies in ADSL.
Remember, ADSL is radio frequencies. A filter that would stop or block
surges would also block ADSL signals. And a shunt mode filter with too
much capacitance would short circuit (leak) too much ADSL signal to
earth. Extra care is required for a low capacitance protector that is
also rated for higher frequencies - for ADSL.

One of those manufacturers states an important characteristic of
effective phone line protectors:
http://www.telebyteusa.com/catalog/manuals/m0161.htm
This is accomplished by using a ground wire no longer than
10 feet, made of heavy gauge (AWG12) or heavier wire from
the ground stud, on the protector, to a building ground.

That earthing wire is about 2 mm and less than 3 meters because a
shorter distance to earth means better earthing. A common mode surge
earthed before it can enter a building should not seek earth,
destructively, via household appliances. As Andrew noted, destructive
surges are common mode; seek earth ground; require a connection to a
building's single point earth ground.

Andrew Gabriel, in article 45b127c3$0$758$5a6aecb4
@news.aaisp.net.uk, says...
In article ,
The Natural Philosopher writes:
....
IIRC its more that the filters stops the phone injecting anything above
wherever broadband starts..10Khz or so?

Actually, it's so the phone doesn't attenuate the higher frequency
broadband data.

It's both... The broadband splitter's filter prevents the
broadband part of the incoming signals from entering the
telephone-type equipment, since they aren't designed to
provide a matched termination at such high frequencies.
Without the match, it is likely some of the incoming broadband
signal's HF energy will get reflected back into the phone
lines to be seen as as noise.

The filter also prevents any HF noise picked up or generated
by the telephone equipment *and associated house telephone
wiring* from getting injected onto the phone lines, again to
be seen as noise.

The ADSL modem also has a filter, but of the opposite type.
This is to stop the low frequency telephone signals and the
associated LF noise, such as mains hum, from being seen by the
ADSL modem circuits. You don't normally see this since it is
part of the modem design. This is why the splitters only
filter the telephone side and pass the DSL side straight
through.

Note that the pick-up of noise on internal house wiring, from
sources such as fluorescent fittings, thermostats, pin-3 ring
signal, etc., is why the preferred installation is to use a
faceplate or similar splitter mounted as close as possible to
the incoming wires, as mentioned in other posts. This gets
the DSL and the telephone signals separated as soon as
possible so the DSL part can be carried to the modem without
being subject to any additional local noise sources.
--
JohnW.
Replace nospam with the first 3 letters of the current month
to mail me.

"Andy Burns" wrote in message
...
TheScullster wrote:

How do you know which connections to make off the A & B feeds to with
these modules?

B leg should be -48v, but I don't suppose it matters really, even for most
phones they doesn't care, you can get polarity reversals with caller ID
anyway, and when you've passed through a microfilter it should chop off DC
up to 3KHz or so, as the ADSL signal is above that frequency.


the polarity on the legs can affect some analogue modems, but will not
affect ADSL

"w_tom" wrote in message
oups.com...


This is also how BT does it. Their $multi-million computer connects
to overhead wires everywhere in town. Does BT shutdown phone service
for every thunderstorm? Do operators remove headsets so as to not be
shocked by lightning? Of course not. BT even before WWII was earthing
every wire that entered the facility. A surge that is connected to
earth will not go farther inside a building to overwhelm protection at
computer or operator.


BT also has gas discharge devices on every line at the exchange

In article ,
"Rick Hughes" writes:

"Andy Burns" wrote in message
...
TheScullster wrote:

How do you know which connections to make off the A & B feeds to with
these modules?

B leg should be -48v, but I don't suppose it matters really, even for most
phones they doesn't care, you can get polarity reversals with caller ID
anyway, and when you've passed through a microfilter it should chop off DC
up to 3KHz or so, as the ADSL signal is above that frequency.

That's done inside the ADSL modem. The microfilter passes the
ADSL line straight through as a direct connection. (If you
don't have a phone on the line, you don't need a microfilter
at all.)

the polarity on the legs can affect some analogue modems, but will not
affect ADSL

The original CD50's and Hayes Accura modems with BT callerid support
were rather polarity sensitive.

Back in the days of BT Approval, one of the tests for equipment was
that it was not polarity sensitive. This was abandoned with BABT
Approvals (which only care about equipment not damaging the phone
network, and not if the phone quipment will actually work or not).

--
Andrew Gabriel

Rick Hughes wrote:
BT also has gas discharge devices on every line at the exchange

Which was posted:
This is also how BT does it. ,,, BT even before WWII
was earthing every wire that entered the facility. A surge
that is connected to earth will not go farther inside a
building to overwhelm protection at computer or operator.

A protector (ie Gas Discharge Tube) connects from each line to earth
ground. Each GDT does not connect between two lines as with the
Clarity device. That would do nothing useful. GDT during a surge must
connect each wire to earth to provide protection. Furthermore,
separation between GDT and BT's computer is also part of the
protection. Protectors adjacent to electronics do not provide that
additional protection. Just another weakness of that Clarity device.

JohnDW wrote:
Note that the pick-up of noise on internal house wiring, from
sources such as fluorescent fittings, thermostats, pin-3 ring
signal, etc., is why the preferred installation is to use a
faceplate or similar splitter mounted as close as possible to
the incoming wires, as mentioned in other posts. This gets
the DSL and the telephone signals separated as soon as
possible so the DSL part can be carried to the modem without
being subject to any additional local noise sources.

If this pick-up of noise was a problem, then all POTs lines would be
filtered at the service entrance AND the DSL line would run separately
to the modem. But JohnDW is discussing crumbs. These noise sources
are microvolt and nanovolt sources. Totally irrelevant to a DSL
millivolt DSL signals.

Furthermore, POTS phone equipment does not generate 10 Khz noise (of
millivolt levels). Filter to stop 10 Khz noise from POTS equipment -
also arguing over crumbs.

Andrew Gabriel has accurately described the only releveant purpose of
that filter:
Actually, it's so the phone doesn't attenuate the higher
frequency broadband data.

Without that filter, POTS equipment would eat the DSL signal.

Why are DSL filters close to a DSL modem? Convenience. Its just
easier to install. When we install from scratch, we put one fitler
right where the phone line enters a building and we run a dedicated
wire to the DSL modem. It simplifies design. All POTS wires carry no
DSL signals. When putting filters at every POTS phone, then other
wires also carry and reflect DSL signals (and any 10Khz noise that may
be picked up). Separation of a POTS and DSL line verifies DSL is only
on its one intended wire. DSL modem connects directly to the DSLAM in
a CO on one hardwire connection - no branch circuits to other dead end
circuits. Clean, neat, and only one filter to leak off DSL signals
(rather than many). Simpler installation where all other non-DSL phone
wires are also completely separated from (do not carry any) DSL
signals.

But for installers, a filter at each POTS phone with a new connector
(rather than tracing wires and installing a new DSL wire) is easier.

Andrew Gabriel accurate described the only purpose of that filter.
Those other noise sources too small (crumbs) to be relevant.

Andrew Gabriel wrote:

That's done inside the ADSL modem. The microfilter passes the
ADSL line straight through as a direct connection. (If you
don't have a phone on the line, you don't need a microfilter
at all.)

yeah, I realised I'd described it ass-backwards, and said so a bit
further down the thread ...

Rick Hughes wrote:
"w_tom" wrote in message
oups.com...

This is also how BT does it. Their $multi-million computer connects
to overhead wires everywhere in town. Does BT shutdown phone service
for every thunderstorm? Do operators remove headsets so as to not be
shocked by lightning? Of course not. BT even before WWII was earthing
every wire that entered the facility. A surge that is connected to
earth will not go farther inside a building to overwhelm protection at
computer or operator.


BT also has gas discharge devices on every line at the exchange


And IIRC on every master socket in every house..well there s SOMETHING
anti-surge.

BTW surge protectors are only good against induced spikes of relatively
low power from ground strikes adjacent to a line. Nothing will protect
against a direct line strike. I know. I had one.

Most equipment that is connected to phone lines has adequate protection:
If it didn't there would be too many returns on it. The cost of
protecting against a full blown strike is more than the cost of giving
away free replacements when it happens.

In short, don't worry about surge protection.

w_tom, in article 1169334579.460282.230760@
51g2000cwl.googlegroups.com, says...


Andrew Gabriel accurate described the only purpose of that filter.
Those other noise sources too small (crumbs) to be relevant.

In my experience, it's those crumbs of noise that add up when
you are working on installations with a marginal service
anyway. If you have a good service, then, I agree, there is
unlikely to be a problem with the small additional noise.

Cheap, plug-in filters must work somewhere. However, I've an
installation with a reported negative s/n ratio... This was
vastly improved by changing over to a faceplate splitter.

I find it better to at least try to use a single faceplate
splitter to get the signals separated as soon as possible.
It's easier than to try to debug the apparently intermittent
problems in marginal installations when you introduce the
unknown quality of in-house wiring into the equation. As BT
have found, it gives you a convenient point of demarcation :-)

--
JohnW.
Replace nospam with the first 3 letters of the current month
to mail me.

JohnDW wrote:
I find it better to at least try to use a single faceplate
splitter to get the signals separated as soon as possible.
It's easier than to try to debug the apparently intermittent
problems in marginal installations when you introduce the
unknown quality of in-house wiring into the equation. As BT
have found, it gives you a convenient point of demarcation :-)

There may be one downside to a single filter - when all POTS phones
connect to a DSL line at one point via one filter. Too many phones
(too many ringers) may saturate a DSL filter inductor causing a short
reduction of DSL signal when POTS phones ring. I have heard it
reported - but never saw the problem. DSL modems I used would monitor
DSL signal levels - no signal degradation displayed. Apparently these
filters did not suffer inductor saturation with four phones.

Meanwhile, I detest some DSL (or cable) modems that do not provide a
status table with signal strength. How can anyone see a problem if
signal strength (in dBs - not is silly bars) is not reported on a
status page?

In message , Andy
Burns writes
Andrew Gabriel wrote:

That's done inside the ADSL modem. The microfilter passes the
ADSL line straight through as a direct connection. (If you
don't have a phone on the line, you don't need a microfilter
at all.)

yeah, I realised I'd described it ass-backwards,

Is that not normal ?


--
geoff

On Sun, 21 Jan 2007 01:45:38 +0000, The Natural Philosopher wrote:

And IIRC on every master socket in every house..well there s SOMETHING
anti-surge.

Yes but it is only across the pair so any common mode surges will not be
supressed, as described by Mr Gabriel. Lightning induces common mode
spikes and surges that are "looking for" earth.

--
Cheers
Dave. pam is missing e-mail

On 20 Jan 2007 15:09:39 -0800, w_tom wrote:

Those other noise sources too small (crumbs) to be relevant.

When trying to squeeze every last bps out of a DSL connection any
additional noise of distortion is a bad thing. The interference from
distant broadcast MF stations at night (and close ones during the day) is
enough to affect noise and sync rates on DSL. Plotting the number of
symbols v carrier I can see the notches that the close by MF stations
cause. I just wish I knew what punched a blooming great notch at around
300kHz...

A single filter as the line comes in then either site the DSL modem mext
to that filter and run ethernet to the computer/network switch or if you
must a single pair direct to and only to the DSL modem. This keeps all
stubs and bad terminations to a minimum and stops the unbalanced ring
wire injecting noise just to one wire via the ringing capacitor in the
normal master socket.

--
Cheers
Dave. pam is missing e-mail

Huge wrote:
Because 99.997% of ADSL users wouldn't know a dB if it hit them on
the head.

That reasoning tells us nothing useful. 99.97%+ don't even know what
octane is but make sure their gasoline has enough.

dB is even simpler. If dB is 0, then signal is too small. If the
db is 8, then signal is mostly good. If dB approaches 20, then DSL is
solid. Nothing complex. Speedometers with Kph and Mph numbers are
more complex. But then many will deny what they never learned or used.
Back to the original problem. Some modems are designed with dB on
status screens as if the user was an idiot. In another post, the
benefit of that dB number on status screens should be apparent.

Huge wrote:
On 2007-01-21, JohnDW wrote:
I find it better to at least try to use a single faceplate
splitter to get the signals separated as soon as possible.
..
Hear, hear. Much easier to use a faceplate splitter and go ethernet
ASAP.

1) Using a faceplate splitter lets all other phone line in the house
act as antennas for more DSL noise.

2) Faceplate splitter is not as soon as possible. It is as late as
possible.

3) Using 'faceplate splitters' at every phone reduces but does not
eliminate each POTS phone 'eating' a DSL signal. Each filter still
'leaks' DSL signal to a POTS phone. Each filter 'slightly reduces'
signal to the DSL modem (otherwise phone would massively reduce that
signal). Using one filter for all POTS devices means more DSL signal
from CO goes to the modem; less leaked through other filters.

4) And finally, 'faceplate splitters' means many 'stubs'. Each stub
or branch line to a POTS phone is where DSL signal goes up that wire,
reflects back, and creates what also creates ghosting on a TV. These
stubs create reflections that distort a DSL signal because modem
receives reflected copies of that same signal. Putting the filter at
the service entrance means no 'stub' to reflect DSL signals.

If one neither has nor appreciates why dBs on a status screen are
important, then one also would not learn experimentally of these minor
losses and distortions of DSL signal. Therefore one could not
appreciate the concepts; learn why one filter and why no DSL signals on
other branch 'stubs' results in better DSL reception.

Putting a filter (a DSL signal blocking device) closer to a DSL
source means putting the filter closer to telco CO and DSLAM. If wires
that carry DSL signals are wires only going to a DSL modem, then DSL
signal will be cleaner and have less noise.

'Faceplate splitters' mean wires to each filter reflect DSL signals
(distortion) and act as antennas to pickup more DSL frequency noise.
Connecting all POTS devices through one filter at service entrance,
instead, removes these sources of noise and distortion. How much?
Again, this is why a dB number on the status page is so useful.

The Natural Philosopher wrote:
BTW surge protectors are only good against induced spikes of relatively
low power from ground strikes adjacent to a line. Nothing will protect
against a direct line strike. I know. I had one.

Those induced spikes are made redundant by protection already inside
all modem and other appliances. We even elininated surge 'noise' on a
long wire antenna with an NE-2 neon glow lamp (same glow lamp sometimes
inside switches). Induced transients are that trivial.

A protector is installed for a massive surge (direct lightning
strikes) that might overwhelm protection inside all appliances. If
such protection did not work, then BT would shutdown and disconnect all
phone service whenever a thunderstorm approaches. Direct strikes -
common mode surges - occur often to a network of overhead and
underground wires; and made irrelevant because of earthed protectors.

In article .com,
"w_tom" writes:
Huge wrote:
On 2007-01-21, JohnDW wrote:
I find it better to at least try to use a single faceplate
splitter to get the signals separated as soon as possible.
..
Hear, hear. Much easier to use a faceplate splitter and go ethernet
ASAP.

1) Using a faceplate splitter lets all other phone line in the house
act as antennas for more DSL noise.

2) Faceplate splitter is not as soon as possible. It is as late as
possible.

[snip]

Hum -- you misunderstand what a faceplate splitter is [in the UK].
See: http://www.broadbandzone.co.uk/shop/...sedfilter.html

--
Andrew Gabriel

In article .com,
w_tom writes
Huge wrote:
On 2007-01-21, JohnDW wrote:
I find it better to at least try to use a single faceplate
splitter to get the signals separated as soon as possible.
..
Hear, hear. Much easier to use a faceplate splitter and go ethernet
ASAP.

1) Using a faceplate splitter lets all other phone line in the house
act as antennas for more DSL noise.

2) Faceplate splitter is not as soon as possible. It is as late as
possible.

3) Using 'faceplate splitters' at every phone reduces but does not
eliminate each POTS phone 'eating' a DSL signal. Each filter still
'leaks' DSL signal to a POTS phone. Each filter 'slightly reduces'
signal to the DSL modem (otherwise phone would massively reduce that
signal). Using one filter for all POTS devices means more DSL signal
from CO goes to the modem; less leaked through other filters.

4) And finally, 'faceplate splitters' means many 'stubs'. Each stub
or branch line to a POTS phone is where DSL signal goes up that wire,
reflects back, and creates what also creates ghosting on a TV. These
stubs create reflections that distort a DSL signal because modem
receives reflected copies of that same signal. Putting the filter at
the service entrance means no 'stub' to reflect DSL signals.

If one neither has nor appreciates why dBs on a status screen are
important, then one also would not learn experimentally of these minor
losses and distortions of DSL signal. Therefore one could not
appreciate the concepts; learn why one filter and why no DSL signals on
other branch 'stubs' results in better DSL reception.

Putting a filter (a DSL signal blocking device) closer to a DSL
source means putting the filter closer to telco CO and DSLAM. If wires
that carry DSL signals are wires only going to a DSL modem, then DSL
signal will be cleaner and have less noise.

'Faceplate splitters' mean wires to each filter reflect DSL signals
(distortion) and act as antennas to pickup more DSL frequency noise.
Connecting all POTS devices through one filter at service entrance,
instead, removes these sources of noise and distortion. How much?
Again, this is why a dB number on the status page is so useful.


Tom!, Your slipping.. not a word about earthing for lightning;-))....
--
Tony Sayer

On Mon, 22 Jan 2007 09:07:29 UTC, tony sayer wrote:

In article .com,
w_tom writes

(long inaccurate rant)

Tom!, Your slipping.. not a word about earthing for lightning;-))....

Don't encourage him...!
--
The information contained in this post is copyright the
poster, and specifically may not be published in, or used by
http://www.diybanter.com

On 21 Jan 2007 17:11:17 -0800, w_tom wrote:

1) Using a faceplate splitter lets all other phone line in the house
act as antennas for more DSL noise.

Total balls in the UK.

2) Faceplate splitter is not as soon as possible. It is as late as
possible.

Relative to what? Is is "as soon as possible" after the demarcation point
between the telephone network wiring (which you shouldn't mess with) and
your own wiring (that you can).

3) Using 'faceplate splitters' at every phone reduces but does not
eliminate each POTS phone 'eating' a DSL signal.

This is a UK group hence, uk.d-i-y, and thus uses UK terminology. I
suggest you make sure that a) you understand the terminologoy as used by
this group b) that the practises your side of the pond apply this side.

4) And finally, 'faceplate splitters' means many 'stubs'.

Not over here. Use of "microfilters" for every bit of POTs kit has that
effect.

Putting the filter at the service entrance means no 'stub' to reflect
DSL signals.

Now that I do agree with. Which is what anyone, including BT, recomend as
"best practice".

--
Cheers
Dave. pam is missing e-mail

Andrew Gabriel wrote:
Hum -- you misunderstand what a faceplate splitter is [in the UK].
See: http://www.broadbandzone.co.uk/shop/...sedfilter.html

I don't see anything different in that figure. One faceplate
splitter is mounted on the Master Socket or many are distributed
throughout the building. Either way, faceplate splitters are a DSL
filter with connection for DSL modem and for POTS equipment. Same
configuration is used in Asia, N America, etc except the POTS connector
is different. Where is the confusion?

On 21 Jan 2007 17:11:17 -0800, w_tom wrote:

Huge wrote:
On 2007-01-21, JohnDW wrote:
I find it better to at least try to use a single faceplate
splitter to get the signals separated as soon as possible.
..
Hear, hear. Much easier to use a faceplate splitter and go ethernet
ASAP.

1) Using a faceplate splitter lets all other phone line in the house
act as antennas for more DSL noise.

[much blather snipped]

I wonder which bit of "go ethernet ASAP" you failed to understand? Because
the rest of the ******** you posted was irrelevant.