Re: Q.: Message waiting light ... how? [telecom]

On 26 May 2012 17:06:48 -0000, John Levine wrote:

So, my question is: what sorts of signal on the line might be causing that
lamp to light? or to extinguish?

Look up the ADSI standard. There are specific tone signals to turn
the message waiting light on and off.

R's,
John

Thanks, John. Actually, ADSI is far too undisambiguated for Google to be
much help. But [ ADSI Message Waiting Signal Standard ] brought up a
Wikipedia article that may well have answered everything I was wondering:

: Some [stand-alone Caller-ID] units will also display the text "MESSAGE WAITING"
: (similar to ADSI-compliant telephones). These units do not use visual FSK to activate
: their red LEDs, but instead, they briefly "pick-up" the line at certain intervals (normally,
: within two minutes of a new call) to check for a "stuttered" dial tone. The presence
: of a stutter dial tone will activate a red LED; while absence will deactivate it.

.... both what might cause it to go flashing when there's no voicemail
service for it to be reporting about, and why 5-10 seconds worth of fresh
dial-tone may bring that flashing to a halt.

<http://en.wikipedia.org/wiki/Message-waiting_indicator>

Cheers, and thanks again, -- tlvp
--
Avant de repondre, jeter la poubelle, SVP.
.

Relevant Pages