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.

...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

Remember: Once you go over the hill, you pick up speed