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[supercooper]

Hi,

I work for a telecoms company as support on adsl connections.

On a few occasions i have noticed that people on long line that have adsl activated have some trouble sending and recieving fax's.

Ok so you may think its a filter issue?? Wrong.

I have spoken to one of our customers today who has never had a problem with there fax untill the connection went live on the line.   As it stand the connection is not acualy being used as they dont have there adsl kit yet.

Im guessing when BT make live there line for adsl that they change the line card completely in the exhange.

Can anyone confirm my suspictions or has anyone had the same problem?

So far i have 4 people with the same problem, all of which are on a long line.

The problem happens with or without sync.

Ideas??

Thanks Chris

[Astral]

Welcome to the forum supercooper.

I have a fax machine on my ADSl line without any apparent problem but I am close to the exchange.

I'm not sure what frequency the fax signal is at, but I would think it at the extremity of the telephone voice spectrum and may get attenuated to the point where the ADSL filter removes what's left. This is only a guess on my part. I'd be interested to hear what other posters with more current telecoms experience have to say.

[soms]

When a line is broadband enabled the PSTN line card in the exchange is not changed but the line is given a new connection through the broadband equipment where the ADSL service is provided.

Filtering in the exchange broadband equipment and using microfilters at the customer end should ensure that all regular telephony services are not interrupted by the ADSL signal.

As Astral says, fax works fine on ADSL.

It is most likely a filter issue as you say.

Even if they are not using the broadband yet, if it has been enabled they must use filters or problems are highly likely to occur.

Ask them to check that they have their filters correctly installed and if they still encounter difficulties ask them to try their fax machine at their master telephone socket (preferably at the test socket if they have an NTE5 master socket) with a known good filter borrowed from a neighbour or someone.

This will help determine if it is a line problem.

[supercooper]

Hi,

Thanks for the response Guys.

I will now souce an NTE5 and have this fitted at out customers site.

Once this is done i will re post to let you all know the outcome.

Thanks again, Chris

[Ezzer]

As Soms correctly said the pstn card remains the same. The "rejumpering" to provide broadband is usualy done days before the date end user was given by the isp that the service is to commence. The dsl signal is piggybacked on to of the pstn.

The range the fax machine works at is much lower than the bands dsl works at so there should be no conflict between the 2 I havn't come across this problem personaly but I have found another problem which may or may not be the source of what you're getting.

If somewhere on the internal wiring you have a HR-Dis, that is a partial disconection you can get the effect where pstn works fine, dsl is added then you find you can't tone dial (number dialed is never reconised) yet pulse dialing is ok.

Again if you can try from an NTE5 test socket and everything is fine, then it's a case in checking all the terminations in the LJU's and BT's a classic would be more than 3 wires in any one idc. give the wires a gentle tug, if they come away very easly that could be the problem.

Again guessing here the only other thing It may be is if the microfilter's capacitors is in effect allmost like rectifing the digital signal from the fax and weakening it enough to cause the problem

let us know of you source the problem, I'm curious ? 

[supercooper]

I have a Telephone Engineer going to this site on Mon 31st.

Will let you all know the outcome as i also am very interested to why this is happening.

Thanks, Chris

[mr_chris]

Please do, I've only just got around to reading threads after being away, but this certainly looks like an issue with the filters. Perhaps, like has been said, with it being a long line, activation of the DSL signal might just be the straw that broke the camels back, so to speak.

Are BT obliged to provide a line that supports fax?

[graevine1]

I have found that lack of understanding in the field causes the problems foir the customer, a medium push with a written note to the attending Engineer requiring a written response produces a fast response

[kitz]

Just a thought

I have seen mention that some people have had problems with fax machines and the resolution was using 2 filters.

The theory should be that this shouldn't make any difference, but theres too many people who have said it has, and for the sake of the cost of an additional filter then its certainly worth a shot and wont harm.

[PhilT]

I have seen mention that some people have had problems with fax machines and the resolution was using 2 filters.

The theory should be that this shouldn't make any difference

Not really, if the filter has an insertion loss of 50 or 60 dB for ADSL signals on the voice port (the SIN will tell us but it's around there) then two in series has a loss of 100 dB or more so the theory does say that two filters are better than one.

This technique has been used on a variety of fussy equipment including some DECT phones.

The USO specifices a voice line should provide "functional internet access" with a guidance speed (not a minimum) of 28800. I wouldn't go down that route as BT would unplug the broadband router and say "there, it works".


Phil

[supercooper]

Hi guys,

We have installed the NTE 5 and only the Router and fax share this line.

The problem still remains and seems to only affect incoming fax's.

We have tried another fax machine on site which did the same.

I did some tests fax's from our offices.  All the fax attempts failed when using a line with broadband on but they did not fail when using a line without broadband on.

We have confirmed again that all of there customers that have broadband on there fax lines cannot seem to sent a fax to this customer.

Im at a loss with this at the moment :/

Chris

[PhilT]

We have installed the NTE 5 and only the Router and fax share this line.

The problem still remains and seems to only affect incoming fax's.

I'm not clear if you put a filtered faceplate on the NTE5 or just added an NTE5. If you put a filtered faceplate on it then plug a standard dangly microfilter into the phone port to double filter it and see if that helps.

If you haven't used a filtered faceplate try two microfilters in series.

Worth saying that the fax has to go in the phone port, just in case 

Last option would be to try the ADSLnation XF-1e "money back guarantee" filter which claims to be the best and beat most of these issues.

Phil

[supercooper]

My company have decided to cease the broadband and install another line to place it on.

I guess we will never know if the 2 inline filters would have cured this problem.

Thanks for your posts and suggestions guys.

Chris

[supercooper]

Hi guys,

Im back 

We have another customer with the same problem, i asked my Engineer to try the double filter idea as suggested by a few of you. It worked a treat   thanks for your help guys.


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[kitz]

We have another customer with the same problem, i asked my Engineer to try the double filter idea as suggested by a few of you. It worked a treat   thanks for your help guys.

Brilliant - glad it worked.

Thanks for letting us know