jrd@mit-amt.MEDIA.MIT.EDU (Jim Davis) (12/13/88)
Has anyone out there got experience with using modems via cellular phone? My experiences thus far have not been good. I have been using: an NEC P9100 phone with booster (3.0 Watts) a Morrison and Dempsey AB1 Cellular Data Adapter a Touchbase Worldport 1200 baud battery powered Hayes compatible modem on the cellular end, a Practical Peripherals 2400 SA modem at the base (set to 1200 baud, of course) Cellular One (non wireline) service from Cambridge. My tests thus far have been conducted while stationary. I have set the modems Hayes compatible parameters S7 (Wait for Carrier after Dial) and S10 (Lost Carrier to Hang Up Delay) both to 60 seconds. I have not done much testing, because air time is costly. My tests have been to transfer files and compare characters for differences. So far, I've gotten quite a lot of noise on the line, but the modems have not dropped carrier. I have been considering getting a pair of Morrison and Dempsey AB2XT modems, (which are said to use MNP level 4) but lately they don't answer their phones (or rather, a voice mail machine takes a message, but nobody calls back) 1) Does anyone know if M&D has closed? 2) Does anyone have experience with cellular modems? 3) Is there any other modem suitable for use in a car which uses MNP error correction? -- Internet: jrd@media-lab.media.mit.edu Phone: (617)-253-0314 USMail: E15-325, MIT, Cambridge, MA 02139