What is Packet Radio? 

Packet radio is computer-to-computer communication using radio links 
rather than telephone lines. Instead of sending a continuous stream of 
information, data is assembled into neat little bundles called packets. 
These packets are sent one at a time. When a packet arrives error-free, 
the receiving station sends an "okay" message (called an ACK) and the 
next packet is transmitted. If the receiving station detects an error, 
it discards the faulty packet and does nothing. After a certain amount 
of time has passed without an ACK from the receiving station, the 
transmitting station sends the packet again. These exchanges take place 
at high speeds, resulting in efficient digital communications without 
errors--a remarkable feat for a radio-based computer network! 

Amateur packet exists as a loose global network. Through packet radio, 
you can tap into this continuously flowing stream of data and exchange 
information with stations throughout the nation and the world. From the 
fascinating to the absurd, it's all on packet! 

Most VHF packet activity takes place on 2-meter FM. You'll also find 
packet on 222 MHz and 420 MHz. Packet is alive on 6 meters as well--with 
many opportunities for packet DX. 

What Can I Do With Packet? 

The answer depends on your interests! Every amateur has different uses 
for packet. Some view packet as a tool to enhance their overall 
enjoyment of Amateur Radio. Others take it further, using packet as 
their primary means of communication. 

To make things simple, let's list the most popular applications of VHF 
packet as it exists today: 

[ ] Enjoying live keyboard-to-keyboard conversations. 

[ ] Accessing packet bulletin boards to exchange messages with other 
amateurs and read general interest bulletins. Some bulletin boards offer 
additional services such as electronic call sign directories and 
magazine bibliographies. 

[ ] Participating in the ARRL National Traffic System. (Packet bulletin 
boards can be used to receive and originate NTS traffic.) 

[ ] Using DX PacketCluster systems to hunt HF or VHF DX. Through 
PacketClusters you can determine which DX stations are on the air at the 
moment--and where they are! DX PacketClusters support other useful 
features as well. 

[ ] Monitoring and communicating with amateur satellites. Many 
satellites function as orbiting bulletin boards, relaying packet 
messages around the world. Others transmit images that you can display 
on your computer screen. 

A basic packet station consists of a 2-meter FM transceiver, a personal 
computer and a terminal node controller (TNC) or multimode 
communications processor (MCP). TNCs are priced around $130. MCPs, which 
offer other digital modes in addition to packet, typically sell for 
about $300. Almost any computer can be used with the TNC or MCP of your 
choice. All that's required is a compatible terminal program. Some 
dealers listed in the pages of QST offer terminal programs for as little 
as $10. 

For 2-meter packet operating, fancy antennas are not required. A simple 
ground plane is fine for most areas. If packet activity is hot and heavy 
where you live, just the rubber duck antenna on a hand-held transceiver 
may be all you'll need! If you'd like more information, pick up a copy 
of Your Packet Companion at your favorite amateur dealer. You can also 
order this book directly from the ARRL.--WB8IMY