Ham radio has long been a playground for innovation and experimentation. Among its most fascinating realms lies the world of packet radio and Automatic Packet Reporting System (APRS). These technologies showcase how digital modes blend with traditional radio communication, enabling utilities like position reporting, satellite communication, and messaging.
What is Packet Radio?
Packet radio is a digital mode of communication where data packets are transmitted over radio frequencies, including HF, VHF, and UHF. With the advent of access to lower-cost 900 MHz boards like Meshtastic, packet radio has evolved beyond its traditional forms. Think of it as sending emails or text messages over the radio.
In years past, packet radio required a hardware TNC, but now free software has revolutionized accessibility. Software TNCs like SoundModem, Dire Wolf, and VARA Modems have replaced expensive hardware. A packet radio system still includes several key components. The Terminal Node Controller (TNC), now software TNC, bridges a computer and radio, converting digital data into audio tones for transmission and decoding incoming signals using things like the DigiRig or Signalink. The radio transceiver handles sending and receiving signals, while a computer or Raspberry Pi manages operator communication or runs nodes for Bulletin Board Systems (BBS), Winkink Gateways, YAAP (file transferring), and more.
Bulletin Board Systems (BBS) and Nodes
BBS and packet nodes are vital parts of packet radio’s history and current use. A BBS is a centralized server accessible via radio, allowing users to leave messages, share files, and communicate asynchronously. These systems were precursors to the modern internet for amateur operators.
Packet nodes can relay messages and data across networks, bridging long distances by daisy-chaining signals. Setting up a BBS or node involves integrating a computer with a radio and/or TNC, enabling it to act as a critical link in the network.
Packet radio also supports file sharing, enabling the transmission of documents, images, and other digital files. This capability is invaluable in emergencies or areas without internet access. Use cases range from keyboard-to-keyboard chats to forwarding emails via RF.
What is Winlink and How Does it Use Packet Radio?
Winlink is a global email system operating over radio frequencies. It enables users to send and receive messages in areas without internet access. These stations can operate peer-to-peer or store messages on Winlink Gateway servers, allowing them to be retrieved like traditional email. Packet radio serves as its backbone, transmitting email messages, weather data, and emergency communications.
What is APRS?
APRS, or Automatic Packet Reporting System, is a protocol for exchanging real-time information like GPS-based location, messaging, event coordination, and weather reports via amateur radio. Developed by Bob Bruninga, WB4APR, it operates on 144.39 MHz in North America.
Popular apps for APRS include APRSDroid, YAAC (Yet Another APRS Client), Pinpoint APRS, and APRSISCE/32. By connecting your radio to a TNC or sound card interface and running APRS software, you can transmit your first beacon or message. APRS offers endless opportunities, from satellite integration to experimenting with long-distance messaging.
Packet and APRS Digipeaters
Digipeaters, or digital repeaters, extend the range of packet radio communications. These devices receive data packets and retransmit them, effectively boosting the signal’s reach. This capability is especially important in areas with challenging terrain or sparse amateur radio activity. By strategically placing digipeaters, operators can bridge significant distances, enabling reliable communication even in remote locations.
A digipeater setup typically involves a radio and a TNC such as the Kantronics KPC3+, to manage the retransmissions. Advanced digipeaters may also incorporate filters or rules to prevent network congestion by selectively retransmitting only certain types of packets. In APRS networks, digipeaters are vital for forwarding location beacons, messages, and telemetry data, ensuring these reach their intended recipients. Setting up and maintaining a digipeater is a rewarding project for hams looking to contribute to their local communication infrastructure. With software like Direwolf, setting up an APRS digitpeater has become increasing easy.
Packet radio and APRS highlight the spirit of amateur radio. From troubleshooting packet collisions to designing digipeaters, these technologies inspire hams worldwide. Winlink further showcases packet radio’s versatility by enabling global email and assisting in disaster communication. Plus, it’s just freaking cool.
Explore The Delaware Packet Network (DEPN) https://groups.io/g/depn for more resources. Visit The Packet Radio RF Forwarding Network (TPRFN) https://www.tprfn.net/ to learn about global packet radio forwarding. Don’t forget to check out KC3SMW-7 on 145.610 MHz (via W3SK), and keep an eye on Glenn N3MEL’s monthly PKTNET check-in assignments for active participation opportunities!
Check out KC3SMW.NET for information on setting up your computer for packet radio. Don’t miss the DENN on Tuesday nights, where we routinely engage in packet radio, FLDigi, SSTV, and more!