[geeks] Synchronus Serial

[James Fogg]

Looks like a whole new generation of geeks are ready for amateur packet radio!

To get the distance you want without intermediate repeaters you need the HF
(shortwave) band. Bandwidth in that space comes in 2.5 Khz chunks.  At that
bandwidth, the limit is about 2400 baud. Currently, I think 300 baud is still
the legal limit. This assumes using AFSK (audio frequency shift keying) using a
Terminal Node Controller (TNC). If you are using TNC's, say hello to AX.25, the
X.25 derived layer 2 protocol for packet radio (and some radio terminals used
by police). AX.25 is directly supported by Linux.

Various schemes to directly encode the 10Mhz wide ethernet signal onto a UHF
carrier have been done (mostly in microwave spectrum). I worked on one such
project. The biggie problem is getting bandwidth (hint, its impossible below 5
gigahertz).

=======================================================
	 James D. Fogg, Network Engineer
	Vicinity Corporation - Lebanon, NH

     DESK (603) 442-1751 - CELL (603) 252-1864
     PAGER (802) 742-0280 - HOME (603) 526-7729
            EMAIL jfogg at vicinity.com

If you can read this e-mail, Thank a Network Engineer!
=======================================================