Kitz Forum

Broadband Related => Telephony Wiring + Equipment => Topic started by: displaced on January 22, 2017, 08:28:39 PM

Title: Occasional Loud Clicking
Post by: displaced on January 22, 2017, 08:28:39 PM
We get this problem occasionally -- I wondered if anyone had seen similar before I start monkeying around with our equipment.

We have 3 DECT phones on one base station.  This affects the first phone (used just a couple of metres from the base).  The others haven't been used enough to know for certain if it affects those too.

What happens is we'll push the 'off-hook' button to get a dialtone.  Immediately, over the top of the dialtone we can hear a regular, loud click.  It's about 1 click-per-second -- and is a 'loud' click.  If we make a call, the other party can also hear the click.  Sometimes, we won't be able to hear the click, but the other end can.  And sometimes the click isn't immediately present, but starts during a call.

Out of about 10 calls per week, this might happen once or twice.  And it's not something which hanging up and redialling fixes -- it disappears on its own after a time.

My MyDSLWebStats shows no affect on our VDSL2 service - no SNRM changes or resyncs.

Due to the regularity of the clicks, but intermittent nature of the problem, I'm wondering:  Presumably, DECT does some kind of frequency hopping.  Could it be that we get this noise when DECT picks a frequency that's being interfered with by our WiFi?  We have an 802.11ac/n router sat not far from the base station.

Cheers,
Chris
Title: Re: Occasional Loud Clicking
Post by: 4candles on January 22, 2017, 10:43:21 PM
Interesting...  :hmm:


I would suggest that next time it happens, pull the base cord from the phone socket. That should immediately prove whether it's internal or external.
Title: Re: Occasional Loud Clicking
Post by: tickmike on January 22, 2017, 10:49:01 PM
Have you got a 'fixed line' phone to try. ?
Title: Re: Occasional Loud Clicking
Post by: kitzuser87430 on January 23, 2017, 07:39:56 AM
Electric fence shorting on some vegitation...Are you in a rural location?
Title: Re: Occasional Loud Clicking
Post by: 4candles on January 23, 2017, 10:28:43 AM
The frequency is about right - I clocked a fence recently at 52 pulses per minute.


I would have expected it to be less intermittent though, unless maybe it only causes the problem in damp conditions.


Is there any correlation with the weather?
Title: Re: Occasional Loud Clicking
Post by: displaced on January 23, 2017, 02:11:43 PM
Thanks for the replies!

I'll have to buy a corded phone to test -- or at least try unplugging the base station from the phone socket whilst clicking's present to see if it continues.

There doesn't seem to be a correlation with the weather -- we've had it happen for a few years, rain or shine.  Up until very recently I thought it was my in-laws' phone until my wife mentioned it happens during the dialtone (I never use the landline myself!).

We also had a pair-swap and the DP terminals replaced and updated back in early December.  Oh, and a switch from BT to a LLU in October.  So lots of fiddling has taken place without curing the clicks (or, to be fair making them any worse!).

Also, we're in an urban area -- nowhere near any electric fences! 

Title: Re: Occasional Loud Clicking
Post by: tubaman on January 23, 2017, 03:54:02 PM
If the cordless base station is your only connection to the land line then unplugging it will definitely stop the clicking noise. :lol:
Title: Re: Occasional Loud Clicking
Post by: 4candles on January 23, 2017, 05:12:40 PM
Only if the noise is external.
Title: Re: Occasional Loud Clicking
Post by: j0hn on January 23, 2017, 08:09:01 PM
Only if the noise is external.
I think tubaman was cracking a joke. If you unplug a cordless phone it's definitely going to stop clicking. It's going to go silent as it will turn off.

You really need to get a cheap corded phone. Tesco/Currys/Argos all sell basic corded phones for around a fiver.
Title: Re: Occasional Loud Clicking
Post by: tubaman on January 24, 2017, 08:30:35 AM
I think tubaman was cracking a joke.....

I was trying to.
Clearly it was a bad one.  :thumbdown:

I also get what 4candles was saying as if you just pull the line cord it will show if the noise is on the line or originates from the DECT phone (asuming it still tries to hold the connection with the line cord removed).
 :)
Title: Re: Occasional Loud Clicking
Post by: 4candles on January 24, 2017, 09:05:08 AM
No problem- you are forgiven.  ;)

Yes, the base and handsets will function as normal if the line cord is not connected.
Title: Re: Occasional Loud Clicking
Post by: burakkucat on January 24, 2017, 03:44:57 PM
Let's continue down the path of the unplugged (from the line) base-station and the observation that the clicking continues to be heard via the handset earpiece.

What possible defect could result in that observation? Breakdown of one (or more) electrolytic capacitor(s), perhaps?  :-\
Title: Re: Occasional Loud Clicking
Post by: tubaman on January 24, 2017, 04:01:02 PM
I would expect it to be a bit more consistent if it were a component breakdown issue.
More likely RFI in the 1.9GHz band.
As to where that would be coming from is another question.....
 :-\
Title: Re: Occasional Loud Clicking
Post by: burakkucat on January 24, 2017, 04:13:02 PM
Hmm . . . Intermodulation products with the RF from a radar installation, dependent upon the atmospheric conditions to allow the extended propagation?
Title: Re: Occasional Loud Clicking
Post by: PhilipD on February 02, 2017, 02:51:12 PM
Hi

I would expect it to be a bit more consistent if it were a component breakdown issue.
More likely RFI in the 1.9GHz band.
As to where that would be coming from is another question.....
 :-\

DECT is a digital signal carrying the audio, so if interrupted or suffering RFI it's unlikely to cause a loud click as the phone will know the audio signal is broken and mute for that time, unless of course they are very cheap phones but even then this should be baked into the system on a chip in the phone.  Drop-outs in the transmission on DECT phones are very much like mobile phones, it just breaks up and wouldn't usually add different noises like loud clicks.

Of course the phone could always be faulty and something is going wrong in the analogue stages.

Hope it gets solved.

Regards

Phil