I knew I saved stuff for a reason.......this may help you, if the OP found = a solution.... = from the saved file folder......this was posted by Douglas Wood...not me -------------------------------------------------------------------------= -------------------------------------------------- Cellular modems of the type you are speaking about require a service = provider. These types of cellular modems work by using a Mobile = Indentification Number (MIN), the modem's ten digit phone number. = There are specific ranges of these MINs owned by companies (such as = Cellemetry); your modem gets assigned one of these MINs. The service = provider then watches the mobile backbone (called AMPS) for MINs in = their ranges. When a MIN is detected, the service provider pulls the = MIN (and ESN) from the AMPS system and passes it along to you (at a = cost of about $0.05 per packet). There is no reason why you couldn't put another device's ESN in the = cellular modem's data packet, but since the modem is uniquely = identified by its MIN, doing so would be a waste of time/space. A word of warning: If you DO decide to use this type of modem, keep in = mind that if you transmit too often (Cellemetry modems use only the = control channel; MicroBurst modems use the control channel AND tie up = a voice channel, although they do not send any data over the voice = channel) your MIN will end up in "MIN Jail". Your MIN will then be = prohibited from send any data packets on the AMPS system for up to 24 = hours. This is how AMPS prevents fraudulent use of MINs. Douglas Wood ----- Original Message ----- From: Charles Craft Date: Sunday, April 16, 2006 0:34 am Subject: [EE]: Cellular modem with programmable ESN To: piclist@mit.edu > I've got a home project where a cellular modem would come in handy = > but don't want the recurring expense. > = > Has anyone worked with a cellular modem that allows you to program = > in a ESN? > If I could use the ESN of my cell phone then I wouldn't need a = > data plan for the modem and > odds are pretty good they won't be active at the same time. = --------------------------------- Yahoo! Messenger with Voice. Make PC-to-Phone Calls to the US (and 30+ coun= tries) for 2=A2/min or less. -- = http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist