Filter necessary? If so which?

[samsat]

My ADSL installation at home uses no filter.
The Telkom connection has two outputs, one goes to the router and one to the analogue phone. All works fine.
Why the need for the filter?

My friend has a new ADSL installation. If the router is connected directly to the Telkom line all works fine. The moment any other telephone is connected to the same line, the ADSL line stops working. Could this be an instance where a filter is required?

I tried the filter that came with the Netgear router and it does not work. Will not pass signal to the router or to the telephone?

What's going on here?

Joel

 

[mas]

Hi samsat

The netgear filters can get confusing. if you use the wrong cable in the filter, it will not work, i struggled for hours figuring out why the filter not working, all I did was switched the cables and it worked. You will see 2 cables with labels on them saying (Filter).

With regards to the ADSL line not working, the filter just filters the Analogue line and not your Data line.

The filter is basically used to filter your analogue output while you using your ADSL output so that you can use the telephone and surf the web at the same time.

I may be subject to correction.

 

[thisgeek]

With regards to the ADSL line not working, the filter just filters the Analogue line and not your Data line.

The filter is basically used to filter your analogue output while you using your ADSL output so that you can use the telephone and surf the web at the same time.

I may be subject to correction.

You are 100% correct.

 

[samsat]

Thanks Mas.
Reading the documentation, it says that the filter reduces any interference on the analogue line but it can still be used without one as I am doing here.

It still does not explain the weird problem at my friends house?

Streak

 

[mas]

My friend has a new ADSL installation. If the router is connected directly to the Telkom line all works fine. The moment any other telephone is connected to the same line, the ADSL line stops working. Could this be an instance where a filter is required?

What's going on here?

Joel

thats quite strange, try using another telephone , which i doubt is the problem, but just try another telephone and see what happens. keep us posted as to what happens.

 

[thisgeek]

Technically, any analogue device that is connected to your line where ADSL is in use requires a filter.
You're better off using a filter, even if you think you don't need one.

 

[SuperAntMD]

Here it is, i'll try to make it brief.

Normal voice uses a very small percentage of the capacity of the copper in your phone line, so ADSL was designed to use up the "wasted" portion of the coppers capacity (i.e. using more of the frequency spectrum).

If you don't have a filter on your ADSL line and you plug in an analogue phone you will most probably beeps, clicks, and strange noises as a result of these additional frequencies.

So yes you should have a filter on an anologue line but it is not essential, as for the ADSL portion of the line stopping to work when you plug in a normal phone that is down right strange and i dont think a filter is your main problem here but i could be wrong.

 

[ICE-VaPa]

mmm, I have the exact same problem as your friend...

If i plug in more then 1 telephone on the same line, the adsl wont connect. - even with 1 telephone connected, the adsl drops throught the day...

I only have a filter on the line with the fone, ive tried many combinations.

 

[krycor]

The filter i always thought worked in two was.. keeping the high pitched(well if you can hear it ) out and keeping the noise away from the adsl equip. Remember, older and other phones phones were NOT designed for adsl, so they assume you just want a clean band for the pots section. ie. there could be some noise/interference caused.. best way which always seems to work is when the phone rings, it usually drops the adsl line. Usually if speakingon the phone/ringing causes the line to drop it indicates you need to relook at that filter first. filters do become faulty but usually the like that out of the box rather than working and then becomming faulty.

Another thing to remember, if you have 2 phones and 1 rings nicely and the other intermittent/or both do it, it could be you have a short somewhere Also i read somewhere about the max phones you can attach to a line pending on design of phone.. not sure about that though.

 

[bees]

A client of mine had a fax machine connected to an ADSL line without a filter, and everytime a fax came through, it dropped the modem. So yes, connect that filter...

 

[viper357]

where can we get filters from, only telkom ??

I am a bit confused but I think I have the general idea, every time my phone rings, the adsl line gets dropped, so I need one of these filters ????? Is that right ?

Where on the line do you fit it ?

Thanks guys.

 

[dabouncer]

Connect the filter to your line output and connect your phone into the rear of the filter.

 

[stoke]

I found that my Alcatel Home ADSL modem [yup .. the very first one teklom raped me with] does not work without the filter connected.

If the phone rings I loose the ADSL connection.
If I pick up the phone then I can hear the ADSL data transferring on the line.
If I start dialing the ADSL line drops.

Mebe the quality of the ADSL modem/router also has something to do with the filter requirement.

 

[krycor]

Depends.. also the higher the bit rate of your adsl line the closer the channel selections of ADSL router[not that this would be that bad since we get tiny bit of what is possible assuming they use ADSL2, remember adsl is rate adpative and hops to next channel if alot of noise is picked up on one and there is available channels to hop to]. Nonetheless the older versions of routers[prob using adsl1] will most likely be more susceptable to noise.

The most common times a line will drop when filter is faulty/not present is phone ring, on-hook -> off hook(pick up phone), and fax.

The hearing the adsl is an odd phenomena in the sense that the frequencies adsl use are not audiable to human, but i also notice the bit of extra noise. In particular with mine i can hear when it attempts reconnects and the line is not synching(thats when i run to the phone to check if the line is working) but then apparently my line was 'old' and they replaced a section of it and now i don't hear it anymore.. odd. But then my router also has a high pitched hum i can hear if i switch off everything but my router. Maybe i just got extra special hearing

 

[Peter7]

where can we get filters from, only telkom ??

Yup, just ask for the ADSL POTS filter - think it's around R40 or so.

 

[Sagariouz]

Another filter question...

How many POTS devices (phones) can be installed on one POTS filter?? So, can I connect a filter and then split the line from the filter to two or more phones??

 

[krycor]

As many(pots devices/analogue phone) as you want i think, ie you could if it was setup in your office/home like this, where the main line comes in and splits to two sections, one to the adsl router and the other thru the filter and then spliting to various sections/rooms that will have only pots service. Thing to remember though is the is only xx voltage + current on the line, so you can't exactly have infinite phones, but 2 or 3 works usually.