Bleeping Telephone

[#1]

Have recently gone broadband after many years on dial-up.    Since installing wireless router which I've actually hardwired to PC my telephone gives a short sharp bleep every half hour - sometimes one and sometimes two bleeps. It's regular as clockwork every 30mins and it does it even if router is powered off.  I have filters on all BT sockets and everything is working fine but I'm just cueious to know what it is.
Thanks for any suggestions.

[#2]

Hiya,
Are you able to try turning off the wireless on your router now that you have your PC wired into it?
It could potentially be some strange wireless interference issue.

[#3]

It's a Thomson Gateway router but I can't see any instructions in it's leaflet about turning off wireless.
As I say. no real problem just occasionally annoying.

[#4]

But you say it still occurs with router turned off - is that correct. If so it can't be the router can it ?.
Not that it make a difference - have you turned of and completely disconnected the router ? - does the phone still bleep.
If so there must be a fault either with the phone , the line or the exchange.
Have you another phone to try ?.

[#5]

I'd be more inclined to go with dodgy filter.
It's not going to be the line or the exchange imho.

[#6]

Fair comment - I should have suggested removing filters as well as the router

[#7]

Thank you all for suggestions, will try them all out tomorrow and report back.

[#8]

Well, thanks to your suggestions and by process of elimination I have found that the bleeping only occurs when one particular telephone set (I have 3 connected throughout the house) is sharing a filter with the router into BT socket.  When that phone is plugged direct into BT socket (ie as I was before I had B/Band) then no bleeps.
None of the other phone sets cause bleeps if substituted into the filter with the router.
Even get the bleeps when router is disconnected from power. As I said the bleeps come almost exactly every half hour. The offending phone set is just a bog standard BT Decor 1200 with LCD display.
So there you have it folks, WEIRD but I can live with it now I know where the cause is.
Thanks for your interest.

[#9]

I'm sure you would prefer to stop it doing that, even if you know the cause! I would suggest replacing the filter with one of these.

[#10]

Thanks for that. I'll give it a try.
Graham

[#11]

The Decor 1200 checks for voice messages using the 1571 service by going off-hook and checking for stuttered dial-tone.  It will do this at intervals, and also after completing a call.  I suspect this is the cause.

[#12]

Many thanks, that sounds like a very plausible explanation - fits in perfectly with what I'm getting.
I think I've overcome the annoyance with much juggling of filters so 'fingers crossed'.