I have an ic 718 and a laptop that i received from a friend. I used to do
wacars with my scanner and was wondering if there was something that simple in
amateur radio. To use a laptop with my radio, do I always have to have a tnc
or some other peripheral or are there modes that just require a sound jack at
the laptop and the radio?

It's quite common to do PSK31, conversational RTTY, PACTOR, MFSK, and
1200 bit/second AX.25 packet radio using a sound-card interface. The
basic pretty-good interface provides electrical isolation between the
PC and the radio... most commonly audio-transformer coupling for the
audio signals, and transistor or (better) optoisolated coupling for
the PTT.

http://www.packetradio.com is one source for such interfaces, and for
links to various software for Windows, Linux, etc.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
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