amateur packet radio

communications (PR) The use of packet radio by amateurs to

communicate between computers. PR is a complete amateur radio

computer network with "digipeaters" (relays), mailboxes (BBS)

and other special nodes.

In Germany, it is on HF, say, 2m (300 and 1200 BPS), 70cm

(1200 to 9600 BPS), 23cm (normally 9600 BPS and up, currently

most links between digipeaters) and higher frequencies. There

is a KW (short wave) Packet Radio at 300 BPS, too.

Satellites with OSCAR (Orbiting Sattelite Carring Amateur

Radio) transponders (mostly attached to commercial satellites

by the AMateur SATellite (AMSAT) group) carry Packet Radio

mailboxes or digipeaters.

There are both on-line and off-line services on the packet radio

network: You can send electronic mail, read bulletins, chat,

transfer files, connect to on-line DX-Clusters (DX=far

distance) to catch notes typed in by other HAMs about the

hottest international KW connections currently coming up (so

you can pile up).

PR uses AX.25 (an X.25 derivative) as its transportlayer and sometimes even TCP/IP is transmitted over AX.25.

AX.25 is like X.25 but the adressing uses HAM "calls" like

"DG8MGV".

There are special "wormholes" all over the world which

"tunnel" amateur radio traffic through the Internet to

forward mail. Sometimes mails travels over satelites.

Normally amateur satellites have strange orbits, however the

mail forwarding or maibox satellites have very predictable

orbits. Some wormholes allow HAMs to bridge from Internet to

AMPR-NET, e.g. db0fho.ampr.org or db0fho.et-inf.fho-emden.de,

but only if you are registered HAM.

Because amateur radio is not for profit, it must not be

interconnected to the Internet but it may be connected

through the Internet. All people on the (completely free)

amateur radio net must be licensed radio amateurs and must

have a "call" which is unique all over the world.

There is a special domain AMPR.ORG (44.*.*.*) for amateur

radio reserved in the IP space. This domain is split between

countries, which can further subdivide it. For example

44.130.*.* is Germany, 44.130.58.* is Augsburg (in Bavaria),

and 44.130.58.20 is dg8mgv.ampr.org (you may verify this with

nslookup).

Mail transport is only one aspect of packet radio. You can

talk interactively (as in chat), read files, or play silly

games built in the Packet Radio software. Usually you can use

the autorouter to let the digipeater network find a path to

the station you want. However there are many (sometimes

software incompatible) digipeaters out there, which the router

cannot use. Paths over 1000 km are unlikely to be useable for

real-time communication and long paths can introduce

significant delay times (answer latency).

Other uses of amateur radio for computer communication include

RTTY (baudot), AMTOR, PACTOR, and CLOVER.

A huge hamradio archive .

Usenet newsgroup: news:rec.radio.amateur.packet.

(2001-05-12)