POTS/ Micro Filter - Help with ADSL Line Configuration

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hambone

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Back to the n00b questions for me, I recently changed my parents over to adsl from the nighnare that was Voadcom-3G.

Anyway, I have a jack with two outputs that aren't labeled, but the phone works in either one. So then, first I tried to connect the router to the one of the jacks and the phone to the other, all that resulted was a constantly dropping line and the phone sounded super scratchy. Then I swapped them around - same result.

Then I eventually hauled my ass to the shops and bought a POTS filter, connected it to one of the jacks, phone on the side labeled "phone" and router on the one labeled "ADSL". The connection is stable as long as I don't pick up the phone to make a call or the phone doesn't ring. Also, I can only make a call if I physically remove the cord from the router, if I don't its the scratchy fax-like sound on the phone.

I reckon its a fault with the line, 0800 375 375 ie. Telkom reckons I need a micro filter, but I thought I already had one? Whats the difference between a pots filter and a micro filter? Do I need to log a fault or get one of these micro-filters. Incredible connection and Telkom don't have "micro-filters"... I'm quite stuck. Any suggestions?
 
I have experienced a very similar issue at my parents' place. Split connection from the wall goes to the router and to the fax/phone, via a filter supplied by Telkom. ADSL is reliable most of the time, but the phone is very scratchy. Sometimes when a fax comes in, the ADSL drops sync. I don't know the difference between a POTS (DSL) and micro filter. Wikipedia considers them to be the same (micro redirects to DSL):

http://en.wikipedia.org/wiki/DSL_filter

Maybe these are of value (I need to read through them too):

http://mybroadband.co.za/vb/showthr...ly-syncs-when-phone-is-off-the-hook-Any-Ideas

http://mybroadband.co.za/vb/showthread.php?159904-POTS-Filter-on-non-DSL-line

http://mybroadband.co.za/vb/showthread.php?52578-Adsl-line-keeps-dropping

http://mybroadband.co.za/vb/showthread.php?132940-ADSL-disconnects-when-the-phone-rings

http://mybroadband.co.za/vb/showthread.php?55274-Noisy-Phone-Line

http://mybroadband.co.za/vb/showthread.php?58589-DSL-drops-when-phone-rings....-Why

I'll post anything else interesting I find here, because I'm keen to solve this too.
 
Thanks for the search, some of it was helpful... I will continue investigating other possible configurations. Also, can anyone explain to me what the jack is supposed to be doing. Its a long thing, with two holes, no labels. I suspect it may just be a mini-indoor extension, like connect your phone and fax machine? Its different to the one I have at hone which is a) smaller and b) labeled "Line" and "ADSL", which I understand to be a POTS Filter.
 
hambone said:
Thanks for the search, some of it was helpful... I will continue investigating other possible configurations. Also, can anyone explain to me what the jack is supposed to be doing. Its a long thing, with two holes, no labels. I suspect it may just be a mini-indoor extension, like connect your phone and fax machine? Its different to the one I have at hone which is a) smaller and b) labeled "Line" and "ADSL", which I understand to be a POTS Filter.
Click to expand...

Are you sure it's not just a normal splitter, built into the wall socket? The ADSL connection I have terminates in a small white box with two RJ45 sockets -- one for the phone (via the filter) and the other for the ADSL. Neither are labelled.
 
I just recalled that I looked at the SNR values on the router on the noisy line and they were fine. Obviously the frequency range of the ADSL was not affected by the noisy line in this case. However, I can't explain why the ADSL sometimes drops when a call comes in.
 
I doubt its a DSL filter like the one I have at home. I agree, just a normal splitter at my parents house. Which would mean I can connect a pots filter to one of the sockets, have the phone on one of the sockets on the filter and the ADSL on the other socket of the filter, correct? Honestly, I think they made a hash of the jack when they put it in some years ago... its always been a scratchy connection on the phone, but is considerably worse since when the ADSL is connected, before it drops.
 
SabreWolfy, the small sockets are called RJ11 (aka Telephone/ADSL socket) where as RJ45 is for Ethernet cables.

hambone, from what you've mentioned, it seems like the POTS filter that you've bought is broken OR perhaps you don't have all your telephones connected via a POTS filter. If you have an alarm system or fax machine, then they have to be connected through a POTS filter too.

Its very important that you connect the devices on the correct socket in the filter, since the phone socket goes through a low pass filter (which filters out all the higher than 20kHz frequencies) and the ADSL socket goes through a band/high pass filter (which filters out frequencies lower than 25kHz and higher than 3MHz). If you connect the devices wrong way round, nothing should work :)
 
hambone said:
I doubt its a DSL filter like the one I have at home. I agree, just a normal splitter at my parents house. Which would mean I can connect a pots filter to one of the sockets, have the phone on one of the sockets on the filter and the ADSL on the other socket of the filter, correct? Honestly, I think they made a hash of the jack when they put it in some years ago... its always been a scratchy connection on the phone, but is considerably worse since when the ADSL is connected, before it drops.
Click to expand...

The ADSL must not be on the filter. AFAIK the filter is only used when are a telephone/fax is connected downstream.
 
Pada said:
<snip>
Its very important that you connect the devices on the correct socket in the filter, since the phone socket goes through a low pass filter (which filters out all the higher than 20kHz frequencies) and the ADSL socket goes through a band/high pass filter (which filters out frequencies lower than 25kHz and higher than 3MHz). If you connect the devices wrong way round, nothing should work :)
Click to expand...

:erm: So the ADSL has a filter too? I have a box on the wall with two sockets. One cable goes from one of the sockets directly to the router. A second cable goes from the other socket to a (low pass?) filter and then to the fax/phone. Where is the ADSL high pass filter?
 
Pada said:
I can't say if that box does any filtering. I usually open the those boxes myself if I don't know if its simply a 1-to-1 connection/splitter or an actual filter.

Here are a few different configurations of POTS filters (that I've drawn myself): http://www.mediafire.com/imgbnc.php/7d0a1f55d9a0eb42df4325fc3d5ad62e6g.jpg

And here's a link that explains ADSL filters: http://www.epanorama.net/documents/telecom/adsl_filter.html
Click to expand...

Each of the POTS filters you have drawn appears to have two ports on it. The filter I have is connected to one of the two "wall" sockets, but the filter itself has only ONE socket, into which the fax/phone is plugged. Therein, I suspect, lies the confusion.
 
Yes I know I draw only the ones with 2 sockets, but you get filters with only 1 socket one each side (1 in and 1 out). You'll have to find out if its a low pass filter (for the telephone) or a band/high pass filter (for ADSL).

I just wanted to show how you should connect multiple devices on a single filter, etc.
 
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