Telephone Double adapters

Does anyone know if the BT ASDL MF50 filter item code 008072 that meets SIN 346 (Aug 2004) has been designed so that it will not operate with a telephone double adaptor attached? To assist further the identification of the product, the filter design tapers towards the line connecter end and has slightly concave sides.

The reason I ask is that this filter has been sent to me to replace my existing filter as part of the attempt by my ISP to increase my line speed towards its capacity of 3mbps. However, nothing will connect through the filter (broadband or telephone) if I try attaching a double telephone adaptor.

My existing filter BT ADSL MF50 item code 011249, rectangular shape 2" x 1.5" has run 2 telephones and my broadband connection without problems (as far as I know) for 2 years. My ISP is also suggesting that I should change my filter every 3 months. Is this necessary?

Incidently, my attempted speed upgrade is proving troublesome having ranged from 0.1 to 1.3mbps during the 10 day upgrade settling in period. It appears to have settled at the speed that I was previously getting of around 0.45mbps before the exchange was upgraded last year to handle 3mbps from 0.5mbps.

"My ISP is also suggesting that I should change my filter every 3 months. Is this necessary? "

That is a new one and suggests it may be worth ignoring any other advice.

NOTE: The exchange can handle the full 8Mbps, just that because you have a long telephone line you are getting less.

Are you saying the telephone double adaptor does not fit into the phone socket on the MF50? Or that you cannot plug the MF50 into the adaptor and have an extension running off of the doubler too?

If the latter that is not the best way of doing things, as extensions can bring down your broadband speeds

"My ISP is also suggesting that I should change my filter every 3 months. Is this necessary? "

Judging by the apparent high failure rate of BT MF50 filters perhaps the ISP was referring to the average failure time they find. :-)

Edited by deleted (Mon 07-Jul-08 14:57:23)

A doubler does just that - it's just a plug with two sockets moulded on the back and nothing would be "designed not to work" with a doubler. If it isn't working then it's almost certainly either just a physical problem (the bits won't fit together properly) or there is an electrical problem with one or other of the bits.

As Mr Saffron has said using doublers before the filter is bad news. Using the doubler on the phone o/p of the filter will be fine (assuming it fits) as that side of the filter has no ADSL signal so you can't mess it up.

I've a couple in my travelling kit and they seem to survive

Did I hear a little meaow?

This cropped up before recently.

Filters don't "wear out" but they can fail. A decent quality one should last for years.

Perhaps it is just because they are very common but the one I always seem to come across that fails is the MF50.

It's a bit like that fatal water stuff then - apparently a very high % of people who die have drunk some in the preceeding week. I'm sticking to booze - much safer.

Thanks folks for your help to date.

For clarification to you all I confirm that I believe I am using the double telephone adaptor correctly I connected the new filter in the same way as the 'old' filter that has worked happily for 2 years so far as follows: 1) - The filter is plugged into the main or first telephone point on the inside of the house 2) - The broadband cable runs from my computer to the DSL socket on the filter 3) - Into the phone socket on the filter I slip the telephone double adaptor (I have tried both my existing adaptor and purchased a new one in case there was some compatibility problem with the new filter) 4) - Then I plug one phone directly into each socket in the double adapter to give me my two phones working off the filter.

With my old MF50 everything still connects but with the new MF50 connected in this way I get no dialling tone on either phone and broadband fails to connect - I get a message to say that I have a line problem. However, if I remove the double adaptor and plug either phone in turn into the new MF50 I have a dialing tone on either phone and broadband connects as well.

I am therefore, at present sticking with my 'old' filter even if it is true that it may compromise my connectivity speed but I would like to understand if at all possible from the Thinkbroadband collective experience, what the problem might be.

Even with this filter issue, I believe there is potential to speed up my connection (my ISP is still researching this for me - they have admitted to me today to 'internal technical problems'). This filter issue though seems intriguing.

Well you can test whether the new filter makes a difference easily - look at the connection information in the ADSL modem.

As for the doubler sounds more like a physical issue, or your telephones are pulling down the line which was just about OK with the old filter, but new one is marginally different.

Other than the daft 3 month advice from the ISP, what makes you think it may be the filter