Re: Phones don't reliably ring after putting in microfilters

On Mon, 26 Jul 2010 22:54:40 +0100, "Mortimer" <(E-Mail Removed)> wrote:

> I was at a customer's house setting up broadband and put in microfilters in
> all the phone sockets that had phones plugged into them, plus one for the
> socket that the router is plugged into.
>
> He's reporting that since then, intermittently his phones don't ring or else
> give a feeble bleep instead of a proper ring-ring.
>
> Now he may have fallen foul of the REN problem - the RENs of all his phones
> add up to more than the REN limit of the line - but why has the problem only
> been seen since I've added the filters? Surely it would have existed before
> as well.

The problem sounds like an insufficiently sized capacitor in the bell line of
the microfilter. Try a filter of a different brand. The filter itself does
not impose any REN load on the line but it can restrict the current flowing
on the bell line to the filtered phones.

Tony

On Mon, 26 Jul 2010 22:54:40 +0100, "Mortimer" <(E-Mail Removed)> wrote:

> I was at a customer's house setting up broadband and put in
> microfilters in all the phone sockets that had phones plugged into
> them, plus one for the socket that the router is plugged into.
>
> He's reporting that since then, intermittently his phones don't ring or
> else give a feeble bleep instead of a proper ring-ring.
>
> Now he may have fallen foul of the REN problem - the RENs of all his
> phones add up to more than the REN limit of the line - but why has the
> problem only been seen since I've added the filters? Surely it would
> have existed before as well.

I've seen some cheap, imported plug-in filters that don't regenerate the
ring signal on pin3 of their phone output socket. If he has one of
these, then the phone wouldn't even ring if it is an old one needing the
pin3 ringing supply.

I suppose there may be versions of these that connect all the unused
pins, other than those with the filter, between the input and output
phone socket. That would connect the bell wire back to the master socket
with undesirable consequences...

Sounds to me that the filters have too small a ring capacitor installed.

I'd look at putting a master socket faceplate filter (e.g. ADSLnation)
and connect all his phone wiring onto its rear phone punch-down
connectors. The ADSL modem/router can then be plugged into the ADSL
socket or an ADSL-only wire installed from the rear ADSL punch-down
connectors to his remote ADSL location. Then you can throw away all his
plug-in filters that seem to hold a fascination for gnawing animals

--
John W