[OT] Electronics Circuit Help

["Martyn Wendon" <mailing.lists@xxxxxxxxxxxx>]

Hi,

Can anybody with electronics expertise assist with a circuit design for
connecting multiple caller id boxes to a PC serial port?

Background:

I've got four phone lines (well actually 2, but they both have distinctive
ring secondary numbers, so I effectively have 4 sources) and I want to get
caller id information onto my xAP network.

My options are:

1) Multiple Meteors (expensive)
2) One of the Meteor multi-line jobbies (even more expensive)
3) 4 PCI Modems with Caller-Id (Probably an IRQ nightmare, plus PCI modems
with BT caller-id seem to be rare)
4) Some sort of line card (brooktrout maybe, but probably expensive
5) Make something to do it

So I'm going with option 5 :)

So far I've got enough components / parts to follow the details at
http://www.amarok.demon.co.uk/dl/cd50_mod/
and make 4 of them.  However that
gives me an issue with needing 4 serial ports which I'd like to overcome (I
don't want to use a multi-serial card as from a software point of view I'd
rather have the data appear on one serial port).

So I need a circuit of some kind that will take the output of 4 of the
hacked caller id boxes and present it on one serial port.

Me electronics knowledge is limited, although I can use a soldering iron!
Can somebody assist?


Thanks for any pointers,

Martyn