View Full Version : ADSL and PABX queries

06-11-2004, 08:16 AM
I am reasonably knowledgable with computers, but I have had no experience with ADSL and I wonder if anyone can confirm something for me

I run a home business and for convenience I have 2 lines in and and an old Philips SPX6 2 to 6 PABX with phones all over the house and workshop.

The PABX is in a cupboard just by where the 2 lines terminate. If I am correct, the ideal setup would be to fit a single Hi/Lo filter on one line right where it comes in.

I would then connect the PABX on the low pass side of the Filter and take the Hi pass directly to the ADSL Router and from there to the two computers.

I feel that with the filter connected like that, no more filters would be needed on the other phone jacks.

Am I correct?

06-11-2004, 08:47 AM
I think that could work. If the signal for ADSL is split off on the Telecom side of the PABX, it should be okay. I would very much doubt you could do it on the customer side of the PABX - I am not sure the PABX would handle it - although to be honest modems can run through the old PABXs (not hybrid systems, just old analog ones). I didn't realise that people still used these.

06-11-2004, 12:04 PM
That is effectively what I did here.

My incoming line went to a PABX/Fax catcher, and from there to the various phone circuits.

Putting a single in-line filter on the input to the PABX and taking the ADSL connection off before the filter is all that is required, all phone outlets are then filtered.

Billy T
06-11-2004, 12:45 PM
Just remember that the filtered output goes to the PABX, and the unfiltered goes to the router.

The purpose of the filter is to isolate the incoming line from the telephone system at the high frequencies used by ADSL and pass the full unfiltered signal level to the router.

In other words, the router gets a direct, clean and unfiltered connection to the incoming Telecom line.


Billy 8-{)

06-11-2004, 08:03 PM
This isn't really related to your question, but there is a software PBX:

Asterisk (http://www.asterisk.org/) - The Open Source Linux PBX.

06-11-2004, 09:45 PM
We have a PABX installed ... don't use it though ...

It's a National Telephone Systems London 8, the sheer fact that it's there makes me feel better about myself as a person.

07-11-2004, 04:40 AM
I wish to sincerely thank all those who took the time to reply to my query and I am happy now that I am on the right track.

The SBX6 may be old (circa 1986) but has performed flawlessly since I purchased it second hand about 14 years ago and is essential to my sanity running a home business as I do.

Many thanks everyone