Phone problems after thunderstorm

"Mike S."

** You need to go to her house and get the real facts. ** More likely storm water has got into the wiring ( anywhere from the exchange to the house) and is causing signal loss & noise on the line - that will screw up caller ID.

..... Phil

Try borrowing a known good caller ID phone and take it over to granny's house. I'd guess it doesn't work, either. Sounds like something's wrong with her wiring.

But either way, you'll definitely get an answer by trying a known good phone in the house circuit.

Good luck Chris

That sounds more like a phone company service issue.

the CID service sounds like its not getting properly translated from the service to your lines. Your phone in effect is picking noise that is screwing up the decoding or, the encoding of the CID signal is incorrect which should be a phone company issue in both cases.

"

what is the audio quality of the phone like? If it is crackly, then water might have got into the phone line (they sometimes use airtight pipes to run the cables inside). This will mess up the caller id signal.

I cannot imagine it is anything to do with the electronics of the caller ID chip. The front end of all phone circuits is quite high voltage with transient suppression on it, so should be fairly robust.

As Chris suggested, either take a good phone to her house, or bring her phone to your house...

Rgds

Bill Electronworks.co.uk - electronic kits for education and fun

:what is the audio quality of the phone like? :If it is crackly, then water might have got into the phone line (they :sometimes use airtight pipes to run the cables inside). This will mess up :the caller id signal. :

Not correct...

The main junction cables between exchanges are usually pressurised (usually dry air) to prevent water ingress when minor damage like pin holes in the sheath occur and to generate an alarm to bring the attention of the telco to the fact that the cable is leaking. Pressurising the cable does NOT have any deleterious effect on caller id or any other signals travelling along those cables.

Usually, if water ingress takes place on a subscriber pair it will produce quite loud 50Hz hum (60Hz in the US) and it may even permanently loop the line if bad enough. It may also reduce the level and s/n ratio of dtmf signalling.

"Ross Herbert"

** Due to all the AC supply frequency current flowing about the soil as a result of the MEN system ? ** Would the fact this signal arrives during the high voltage ringing cycle make matters worse ?

..... Phil

In the US they often toss power and phone lines into the same trench. That's also how it is at this building.

AFAIK the ID is transmitted between the 1st and 2nd ring, not during the ring cycle.

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:Phil Allison wrote: :> "Ross Herbert" :> :>> The main junction cables between exchanges are usually pressurised :>> (usually dry :>> air) to prevent water ingress when minor damage like pin holes in the :>> sheath :>> occur and to generate an alarm to bring the attention of the telco to the :>> fact :>> that the cable is leaking. Pressurising the cable does NOT have any :>> deleterious :>> effect on caller id or any other signals travelling along those cables. :>>

:>> Usually, if water ingress takes place on a subscriber pair it will produce :>> quite :>> loud 50Hz hum (60Hz in the US) and it may even permanently loop the line :>> if bad :>> enough. :> :> :> ** Due to all the AC supply frequency current flowing about the soil as a :> result of the MEN system ? :> : :In the US they often toss power and phone lines into the same trench. :That's also how it is at this building. : :> :>> It may also reduce the level and s/n ratio of dtmf signalling. :> :> :> ** Would the fact this signal arrives during the high voltage ringing cycle :> make matters worse ? :> : :AFAIK the ID is transmitted between the 1st and 2nd ring, not during the :ring cycle.

Here's the official ACIF (Australia) description - it just says CLI info is transmitted "during" the ringing stage, but that could well be between ring bursts. The "normal" ring cycle in Australia has a period of 3 sec (0.4 sec ON,

0.2 sec OFF, 0.4 sec ON, 2 sec OFF), and so on.

QUOTE Transmission of CLI to telephone call recipients (Called Party, B-Party) When a call reaches the terminating telephone exchange, that is, the exchange to which the called party's line is connected, the exchange normally checks the Address Presentation Restriction Indicator.

If the APRI is set to "presentation restricted" the exchange does not (should not) send the calling party's number down the line to the called party.

If the APRI is set to "presentation allowed", the exchange transmits the calling party number during the ringing stage of delivery of the call to the called party (if the called party is subscribed to the CLI Presentation service).

The called party's telephone answering equipment may receive the calling party's number in various ways including: in the form of information that is displayed on a telephone or computer screen, or automatically recorded in a database, or as an audio message, etc.

: :"Ross Herbert" : :>

:> The main junction cables between exchanges are usually pressurised :> (usually dry :> air) to prevent water ingress when minor damage like pin holes in the :> sheath :> occur and to generate an alarm to bring the attention of the telco to the :> fact :> that the cable is leaking. Pressurising the cable does NOT have any :> deleterious :> effect on caller id or any other signals travelling along those cables. :>

:> Usually, if water ingress takes place on a subscriber pair it will produce :> quite :> loud 50Hz hum (60Hz in the US) and it may even permanently loop the line :> if bad :> enough. : : :** Due to all the AC supply frequency current flowing about the soil as a :result of the MEN system ?

That's what I would imagine to be the reason for 50Hz hum. Moisture ingress into a cable will effectively connect the cable pairs to earth via a high resistance as well as producing a shunt resistance across the pairs.

: : :> It may also reduce the level and s/n ratio of dtmf signalling. : : :** Would the fact this signal arrives during the high voltage ringing cycle :make matters worse ? :

It sure would. Depending upon the ringer in the destination exchange the ringing voltage can exceed 120V pk-pk. This will break down a high shunt resistance due to moisture ingress and can even result in ring trip without lifting the B party handset.

Hi Ross

I was referring to the water getting into the cable deteriorating the signal, not the pressurised line deteriorating the signal.

I had problems some years ago when water entered my local phone cable. Phone line was crackly, internet bandwidth was nearly zero and caller ID was intermittent. It was due to water ingress into the cables. No hum though - just crackles

Rgds

Bill Electronworks.co.uk - electronic kits for education and fun

"Electronworks.co.uk"

** Water plus copper wires plus DC voltage

= recipe for TROUBLE !

..... Phil