Jim,

I think you'd be far better off buying a popular cellular phone and
interfacing it. You have the BIG cost advantage of "It already works".
You won't have to deal with the cost and difficulty of
designing/debugging a finicky RF section and meeting ALL the
regulatory specs. Buying a mass market product ensures that
you will have a much lower unit cost AND and an ongoing supply of
used phones to draw upon should your supplier discontinue the model.
Try replacing a chip set 3 years from now. 486/66 anyone?

By going with a mainstream supplier like Nokia (DO NOT USE ERICSSON!
I have had 3 bad KF788 phones from them, and they hose you on accessory
pricing) you may also find a uniformity of interface protocol across the
various phone technologies
(GSM, TDMA, CDMA). IOW all 61xx series -seem- to have the same interface
connector pin out and respond to the same subset of serial port
commands. Clearly if you can control the phone to send a fax,
you can just as easily control it for voice data (not considering
the all-digital mode).

What is your time worth to build/debug/get regulatory approval of
a phone module
 VS
buy the phone, buy the cable, connect the leads, and start programming
the -project-?
Some things just aren't worth reinventing, or were you also looking
at designing your own microcontroller and development tools?

And if you're not fussy, you can pick up used Motorola bricks for
about a dollar at garage sales, and there is LOTS of info on the web
on controlling/hacking them.

You might also want to contact your local TV station if it uses
one of those electronic maps that show you temperatures from all
over your state in real-time. I don't recall the name of the company,
but the system uses cell phones at the remote locations, and it
calls the remotes to collect the live data during the weathercast.
Their technical people might be willing to discuss the 'gotcha's'
of their interfacing experience.

Jim Dolson wrote:
>
> Has anyone incorporated a cell-phone chipset into a project?  I would
> like to give one of my projects the ability to place a cell-phone call
> (to play recorded audio - not data), but I don't have the foggiest idea
> where to start.
>
> I thought of simply buying an interface cable and plugging into an
> existing cell phone, but I'd rather use whatever chipset a cell-phone
> uses instead of buying an existing cell-phone.
>
> Has anyone done this before?  Anyone recall a magazine article?  Thanks!
>
> Jim
> wb8zbd

--
Robert.Rolf-AT-UAlberta.ca