Telephone socket divider issue with ADSL Internet

Justin_H · 14-10-2010, 22:45

Dear All,

A computer and PoE hub is placed upstairs in a restaurant (in order to use a webcam as a security camera). Due to the current arrangement of the telephone line, the ADSL broadband modem is placed upstairs, directly above by one floor from the phone socket. The phone socket is used by the counter to take telephone orders. This telephone line is now being used to also gain broadband from BT. A standard telephone-socket-divider has been used to split the telephone and the broadband connection. A phone line is used for the broadband that extends all the way to the floor above where it is then attached to an ADSL filter which is connected to the modem.

Problem: if the divider is not used at the phone socket by the counter, the modem upstairs can connect to the Internet just fine. When using the telephone-docket-divider however, the telephone works fine by the modem cannot connect the the Internet. The flashing green light implies that it is trying to connected. I think the trouble is to do with the signal disruption of the line due to the divider, however I'm not sure.

Please could you let me know what you think the issue is and how to resolve it (or what steps I could take or where to look).

Thank you,
Justin_H

Matth · 15-10-2010, 18:38

Do you have another filter for the phone on the divider.

So it's divider, line to upstairs, with adsl filter for modem.
Other outlet of divider, adsl filter to phone.

Anything other than the modem, MUST pass through the phone side of a filter, otherwise the ADSL signal will be severely impaired, resulting in no connection or slow and unreliable connection. This includes faxes, answerphones, alarms, extension bells, sky box, or a PC 56k modem.

Justin_H · 16-10-2010, 11:53

Quote:

Originally Posted by Matth

Do you have another filter for the phone on the divider.

No I don't, the telephone seems to work fine without a filter.

Quote:

Originally Posted by Matth

1- So it's divider, line to upstairs, with adsl filter for modem.
2- Other outlet of divider, adsl filter to phone.

1 - yes
2 - just outlet of divider to phone, no adsl

Quote:

Originally Posted by Matth

Anything other than the modem, MUST pass through the phone side of a filter, otherwise the ADSL signal will be severely impaired, resulting in no connection or slow and unreliable connection. This includes faxes, answerphones, alarms, extension bells, sky box, or a PC 56k modem.

The filter I've been given is a phone and adsl divider actually. I'll try placing this at the telephone socket outlet downstairs.

Thanks for your help.

Graham M · 16-10-2010, 17:10

It's not the phone that won't work without the correct filter, it's the net connection

Justin_H · 16-10-2010, 18:12

Diagram of the set up:

Graham M, do you still suggest the ground floor telephone requires an ADSL filter even though it is working fine?

Paul K · 16-10-2010, 18:30

Any socket on your line that is in use needs to have a filter on the socket before anything connects to it.

Graham M · 16-10-2010, 18:51

Yep any socket that has anything plugged into it needs a filter, the filter is there to separate the voice frequency signals from everything else

handyman · 16-10-2010, 20:34

Plug the adsl filter into the socket and run the phone off that and purchase an extended rj11 broadband cable off ebay to go up to the modem.

Justin_H · 17-10-2010, 14:06

Thanks Paul, Graham M, I'll try this first.

handyman: Cheers, I was thinking about doing this, I'll try this second if the above solution doesn't work.

Matth · 17-10-2010, 23:42

The purpose of the filter is to split the ADSL and phone signals, preventing the ADSL signal causing noise on the phone, and preventing the phone from sucking out the ADSL signal - if you plug an unfiltered phone in, it effectively shorts out the ADSL frequencies.

Simple solution, if you have a 99p store nearby, they may have ADSL filters (mine does), just pop a filter on the phone and it should work fine - actually, you want your best quality filter on the phone, and maybe use the cheapo on the modem, as if the filter is of less than ideal quality, it will be less of an issue if only used as a connector (the ADSL side just connects straight through, only the phone side is filtered).
http://www.adslnation.co.uk/support/filters.php

Justin_H · 18-10-2010, 07:54

Thanks for the further explanation and link Matth, appreciate it.

Justin_H · 24-10-2010, 00:20

The ADSL filter has definitely done the trick: the broadband is working now.

However, the speed is very slow. Getting download speeds of 0.25 Mb/s whereas before it was a good 4 Mb/s. I assume this is because of using an extended phone line cable? I'll buy an rj11 cable to go up to the modem instead.

Graham M · 24-10-2010, 02:03

Could be poor wiring on the extension, how long is it and how is it connected to the socket/

Matth · 24-10-2010, 14:01

If you are using a second fliter, try swapping them if they are different types, according to that page on them, some actually have an inherent fault.

If it worked ok with the extension and no phone, then it sounds like the filter on the phone may be a poor one.

Ideally though, filtered plate and RJ11 to the modem would be best.