[comp.protocols.tcp-ip.ibmpc] PC SLIP -> modem -> slipserver ?

JFISHER@ISDRES.ER.USGS.GOV ("James R. Fisher 703-648-7026") (05/30/91)

I have the slip packet driver and Clarkson/NCSA telnet on a PC,
can load the driver ok , modify config.tel suitably and crank up
telnet, but obviously something's missing. How do I talk to the
modem to tell it which number to dial to get to the distant host ?
Perhaps I have a theoretical discomprehension of how this thing's
supposed to work. Does anyone know of a 'bonehead-user's guide to
PC SLIP' they could point me at ? 
Many thanks in advance. -jrf