ADSL filters and cordless phones
I had a phone call from a widowed friend to say her Internet was down. She had spent about 2 hours on the phone to her ISP (Clear) and all they could suggest was that her Modem (a Dynalink RTA1320) was faulty
I called yesterday and and found the Modem power LED was steady and green, the Ethernet and DSL lights were on but the PPP light would flash 5 or 6 times, then go out and repeat 10 seconds or so later
I was able to Login and retrieve the settings and then hooked up another RTA1320 that I had brought with me.
Exactly the same result… Hmmmmm… so not modem
I then hooked up a S/H D-Link DSL502T that I had also brought with me and after initialising, it was OK and going
What the Hell!!
I reconnected the Dynalink and still the same problem.
Next I unlugged the other 3 phones on the network. 1 x Panasonic Cordless and 2 x Analogue
After 20 secs or so the Modem fully initialised so we had an external fault somewhere.
I reconnected the 2 Analogue Phones (and their filters of course) and everything still worked 100%
So I plugged in the cordless and the fault returned.
A bit of head scratching, then as a test I swapped the filter on the Cordless (a D-Link filter) for one on the nearest Analogue phone (a Dynalink Filter) and the modem was rock solid.
I tried the other 2 modems again and they were both operating 100%
I left it like that, but I suspect that perhaps something in the Cordless Phone did not like the D-Link filter
Spurious RF perhaps?
I have no idea, but it works and I am happy with that.
I see so many of these issues with customers these days, the filter, the DSL line and the router… So many things to check for the rootcause!
Agreed. Many filters don’t last very long – they might even look ‘rusty’ or burnt on the inside which is a giveaway.
Dodgy filters can be intermittent and frustrating to diagnose. If in doubt just replace it – fortunately they’re cheap and many people will have a spare anyway as new routers usually come with a few of them.