Channel Vision whole house DSL filter - Reply to all

["Bill Stock" <me7@xxxxxxxxxxx>]

I'll reply to all who answered below, since Robert has the most detailed
reply.

"Robert Green" <ROBERT_GREEN1963@xxxxxxxxx> wrote in message
news:DcKdna38QZfW7pbbnZ2dnUVZ_vmqnZ2d@xxxxxxxxxx

>> 1) How does one wire up the RJ31 jack? i.e. what wire goes where?
>
> An RJ31 jack is typically used a line seizure device.  Since it's critical
> that the alarm panel is able to dial out immediately when an alarm is
> triggered, the RJ31 jack allows the alarm panel to disconnect any phone
> call
> in progress *downstream* from the jack and then grab a dial tone and dial
> out.  That's why they are almost always the very first device connected to
> the phone network after the phone line enters the home.
>
> DSL complicates the issues because some people want to be able to seize
> the
> voice line so the alarm can dial out WITHOUT interrupting their DSL
> connection (which could be relaying images from the house cameras that you
> might want to see remotely to confirm an alarm condition exists).
>
> Which do you want to do?  Is it acceptable to you for the DSL line to go
> down when your alarm dials out?

I don't care if I lose the DSL when the alarm is engaged.

> The RJ31 jack is larger than a regular RJ11 phone jack because the phone
> lines must be able to enter the jack, go into the panel, through the
> "line-seizure" switch, back out through the jack and finally on to the
> phone
> wires that serve the household phones.  The reason for extra wire is that
> one pair is goes to the alarm panel and the other pair is used for wiring
> downstream to the house phones.

Yes I took the RJ31 behind the alarm apart to see what goes where.

Pins 1(White), 4(Red), 5(Green) and 8(Brown) are used.  I'll just install a
jack at the other end and duplicate the wiring. (Note to R.B., don't worry I
plan to test it. :-) )

>> I've got an ITI Simon alarm that seems to have four power wires and two
>> phone wires going back to the alarm panel. I gather I just need to wire
>> up
>> the red/green to the center of the RJ31 connector.
>
> It depends.  If the unit is already set up to seize the line in a case of
> an
> emergency, all you would do is maintain that wiring.  But I am not sure
> what
> you are connecting to where.  Let's start by ascertaining exactly what you
> are using.  Is this it?
>
> P-0411 ADSL Filter and Surge Module

Yes, that's the one.

> It's got four incoming phone lines and a security system "Bypass/Normal"
> switch on the front.
>
>> 2) There is still static on the phone line, even with the filter
> installed.
>> Modem seems to work OK, so I'm not sure if the filter sucks or I have a
>> connection issue.
>
> I'd probably start at the entry point, plug a phone into the network
> interface CAP jack to see what I heard and mentally gauge the interference
> level.  Then I would split that line to a filter (you should have gotten a
> few RJ-11 filters with your DSL kit) and the other to the DSL modem.  You
> should be connected to just that splitter and none of the other phone
> wiring
> in the home at this point.  Not even the alarm.  To troubleshoot this kind
> of problem, you really need to isolate components as much as possible from
> each other.  The home phone wiring is a little like X-10 in that different
> types of devices have different impedances and electrical properties that
> can interact badly.


Makes sense. I want to eliminate the alarm from the circuit first (RJ31 at
the filter), then I'll narrow down the source of the noise as you suggested.
Just to be clear, there was NO noise before the modem.

Right now the return from the alarm is running into the filter and then out
to the phones. So it's Alarm --> Filter ---> Phones, which not ideal, but I
doubt it's the cause of my static. Although I've read that this can
attenuate the DSL signal and my transfers are about 10% less than average
for my area and provider.

> I'd make this test because you should now NOT hear any noise on the phone
> connected to the splitter leg that's got the DSL filter plugged into it.
> If
> you do hear noise on the voice side, you may have wiring issues outside of
> your control.

<Good stuff about Robert's wiring snipped>

> Anyway, I would see what I heard through the DSL filter right at the first
> split from the CAP.  Let's get some more info for the traceback:
>
> Do you have one or two or more phone lines?

Right now one, but two at one time.

> Are they properly grounded?  Lots of times phone grounds get loose or
> corroded and that can create a noise problem.  At least inspect it
> visually
> if not with a meter just to make sure.
>
> Is your Channelvision DSL filter mounted nearby and grounded as well?
> There
> shouldn't be any current flowing from the ground connection on the DSL
> filter to the ground connection for the incoming phone line.

Filter is a few inches from the incoming phone line. No way to ground the
filter that I can see.

> There's an interesting discussion of how grounding issues can generate hum
> and noise here:
>
> http://www.dself.dsl.pipex.com/ampins/groundloops/grndloop.htm
>
> Do you want to be able to use any jack in the house for DSL or will there
> just be one or two phone jacks you will use for DSL?

I actually located the modem beside the filter in the 'phone cupboard' and
ran Cat5e to the router in the computer room.

> Is yours a self-install kit?  That saves the Telco's boatloads of bucks
> but
> it often means that no trained technician ever looks at your entrance
> phone
> wires, which could easily be 20 or 30 years old with a badly corroded
> ground!

Yes, it's actually DSL from a 3rd party, but the phone company did all the
setup outside. This is about $15+ cheaper a month and the 3rd party has a
good reputation. Although their installation documentation (none) made it
interesting getting the modem-router to work behind the main router.