Remote Ringer for Telephone
Jim Thompson wrote:
On Wed, 26 Jan 2011 20:58:03 -0500, "Martin Riddle"
wrote:
"Jim Thompson" wrote
in message ...
[snip]
(Existing reject box designers haven't yet figured out how to insert
CID after second ring. Shouldn't it be easy enough with a micro?? )
So you only want to dump incoming 800 numbers, but let every thing else
thru.
The CID appears between the first and second rings.
http://www.epanorama.net/documents/telecom/cid_bellcore.html
So you should be able to grab it and determine if the number should be
hung up,
Before the second ring.
Then you need a V.23 1200 baud modem to reinsert the CID after the
second ring.
Sounds like its doable, lotsa time between rings. A PIC would work. You
would need a blocking circuit for when the modem retransmits the CID.
Ma Bell might not be happy with extra CID data on their lines.
Cheers
That re-insertion is the tricky part.
Not really. Simulate a CO line and insert the CID. If you pick up
the phone, tranfer that phone to the outside line.
--
You can't fix stupid. You can't even put a band-aid on it, because it's
Teflon coated.
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