Operating Packet and APRS

Operating packet and APRS

A complete AX.25 packet station in the browser: frame monitor, connected-mode QSOs, APRS with a station map, and YAPP file transfer. No TNC, no KISS bridge, no separate APRS client. The modem is a built-in Direwolf: on the server in the Server build, as WebAssembly in the browser on Standalone.

Modems	300 baud AFSK (HF) • 1200 baud AFSK (VHF) • 9600 baud G3RUH FSK
Monitor	Live decode: sender, destination, digipeater path, control field, PID, payload
APRS	Heard-stations table, beacon compose, a map of received positions drawn with the APRS symbol set
Terminal	Connected-mode QSO: connect to a station or a BBS, chat, message on Enter
File transfer	YAPP send and receive over an established connection
Waterfall	RX spectrogram of the modem passband with TX bursts marked

Operating

1. Tune to a packet frequency in a voice mode (USB/LSB on HF, FM on VHF). The radio sees a normal voice carrier; wfweb sets DATA MOD OFF itself while it transmits.
2. Open the Packet panel and pick the modem. Frames stream into the monitor as they decode.
3. Terminal tab: type the peer callsign, an optional digipeater path (WIDE1-1 or a specific digi), and press Connect. Once CONNECTED shows, type messages and press Enter. Disconnect ends it cleanly.
4. File transfer: with a connection up, choose a file to send with YAPP; a receive is accepted automatically into a download.
5. APRS tab: stations heard with their last position and comment, a map of them, and the beacon composer (position, symbol, comment) with a schedule. On the Server build the beacon keeps firing with no browser attached; that is intentional.

Station callsign and SSID come from the gear dialog.

9600 baud

G3RUH needs the radio's discriminator output and a flat modulator input (the 9600 or DATA2 jack on rigs that have one, such as the IC-9700, IC-9100 and IC-7100), not the speaker audio. Over the radio's USB codec, which carries de-emphasised speaker audio, 1200 is the practical limit.

Things to know

• One transmission at a time across packet, FreeDV and RADE; a packet TX requested while a voice mode is transmitting fails with a notice rather than queueing.
• A short dead carrier is sent before each frame so the other station's receiver settles; the radio must be in a voice mode with DATA off for the modem audio to reach the modulator.
• The recording of a packet session shows the modem spectrogram, the monitor, and the terminal conversation or the APRS stations, whichever tab is selected.