PC Ext: Reverse Carrier for Voice/Modem Switches

• Microsoft Mail for PC Networks, versions 2.1e, 3.0, 3.0b, 3.2, 3.2a, and 3.5

Voice/Modem switches are used to detect incoming modem calls and direct them to a modem while allowing voice calls to go to a telephone. By default, the Microsoft Mail for PC Networks External Mail program (EXTERNAL.EXE) uses reverse carrier to call all Call/Request users. Reverse carrier causes the dialing modem to call out its carrier, rather than waiting for the answering modem to speak first. This is necessary for Voice/Data or Voice/Modem switches to work properly.

This is a feature of the External program; there is no way to turn it off. However, some modems have a setting for how long to wait after the dial, before calling out their handshake carrier. For example, a Microcom 2400 baud modem has an F7 setting. By setting that register to 30 in the modem script, the carrier will sound immediately after the phone number is dialed; increasing the register to 60 will delay the carrier several seconds.

For more information about reverse carrier, see the owner's manual for your modem.

For more information about changing script files, see Appendix N of the Microsoft Mail "Administrator's Guide."

Microcom modems are manufactured by Microcom Systems, Inc., a vendor independent of Microsoft; we make no warranty, implied or otherwise, regarding this product's performance or reliability.