Digital HF & NVIS Resources

LinBPQ runs as a console application or daemon and is managed entirely via a web browser. It is the recommended platform for hub stations due to better uptime and resource efficiency versus Windows.

• Download the latest binary from G8BPQ Downloads Page ↗
• Place the linbpq binary and bpq32.cfg in the same directory (e.g. /home/user/linbpq/)
• Create an HTML/ subdirectory and unzip the HTML management pages into it
• Run: ./linbpq mail chat to start node, BBS, and chat server
• Management web UI: http://localhost:8080 (port set in cfg)
• Configuration is case-sensitive — BPQ32.cfg will NOT work; must be lowercase bpq32.cfg

BPQ32 is packaged as an NSIS installer available from the BPQ32 Groups.io file section. Configuration is at C:\Users\USERNAME\AppData\Roaming\BPQ32\BPQ32.cfg. Use View Configuration Folder from the Start menu shortcut to locate it quickly.

• Download installer from BPQ32 Groups.io Files ↗
• Run installer — do NOT launch BPQ32 at the end if running as Administrator (file permission issue with VARA)
• Open View Examples Folder from Start menu — copy the example closest to your intended setup and modify it
• Restart BPQ32 after any config changes; it can also re-read config without full restart via the console window

The configuration file uses ; comment for single-line comments and /* ... */ for multi-line blocks. All parameters are KEYWORD=VALUE pairs.

• Download VARA HF from the EA5HVK VARA page ↗ — current version is VARA HF v4.9.0
• Run the installer. On Windows Server, do NOT launch VARA at the end of install — do it manually after to avoid file permission issues
• VARA HF requires Windows or Wine on Linux. For native Linux use, run via Wine or use varanny ↗ for headless/remote management
• Install VARA HF and VARA FM separately — they are distinct programs sharing the same license key

• Open VARA HF → Settings → VARA Setup — enter your callsign and license key if you have one
• Settings → SoundCard — select your digital interface soundcard for both Input and Output. Set your computer's internal soundcard as the default Windows device so VARA has exclusive use of the external one
• Set receive audio so the input meter reads around 12 o'clock (50%) — adjust radio volume or soundcard level
• VARA HF communicates with BPQ32/LinBPQ via TCP: command port 8300, data port 8301 (defaults)
• For running multiple instances, change ports — e.g. second instance uses 8302/8303

VARA HF does not directly control radio PTT or frequency — this is handled via CAT control configured separately in BPQ32/LinBPQ or Winlink Express. Common methods:

• RTS/DTR via COM port — most common for hardware interfaces (SignaLink, Digirig, etc.)
• CAT via CI-V (Icom) — set CI-V baud rate to 115200, CI-V Transceive ON, CI-V USB Port = Unlink from REMOTE
• CAT via CAT5 (Yaesu) — configure baud rate to match your radio's menu setting
• Hamlib / rigctld — preferred for Linux; varanny can launch rigctld automatically

• Download VARA FM from the EA5HVK VARA page ↗ — current version VARA FM v4.4.0
• Open VARA FM → Settings → VARA Setup — enter callsign and license key
• Settings → SoundCard — select your external/radio soundcard. Set your computer's internal soundcard as the Windows default to avoid conflicts
• For digipeater operation, enter your CALLSIGN-SSID in the Digipeater field — requires a license
• VARA FM operates on TCP ports 8300 (command) and 8301 (data) by default — same as VARA HF, so they cannot run simultaneously on the same ports. Use 8302/8303 for the second instance

• Ping individual hops before attempting full connections — use the VARA FM ping function to verify each hop S/N
• Avoid sending traffic on connections with S/N below 10 dB — it ties up the frequency with little chance of success
• VARA FM 4.x.x stations cannot connect to 3.x.x stations — both ends must run the same major version series
• Check your radio's data speed setting — must match NARROW (1200) or WIDE (9600) as appropriate

• Download Winlink Express from winlink.org ↗ — always download from the official page to get the current version (not a pinned older link)
• Run the installer; .NET Framework 3.5 may be downloaded automatically if not present
• On first launch, the Properties window appears — enter your callsign. If you have no Winlink account, enter a new password and your account is created automatically on first CMS connection
• Enter your 6-character Maidenhead grid square (e.g. EM73nl)
• Update Winlink Standard Forms when prompted

• In Winlink Express, change the session mode to Vara HF Winlink from the drop-down
• Click Open Session → in the session window, click Settings → VARA TNC Setup
• Host: 127.0.0.1, Command Port: 8300, Data Port: 8301
• Check Automatically launch VARA TNC when session is opened
• In Radio Setup, configure your CAT control COM port, baud rate, and PTT method
• For Icom IC-7300: CI-V baud 115200, CI-V Transceive ON, CI-V USB Port = Unlink from REMOTE

Build Dire Wolf from source using CMake. All dependencies are available in standard repos.

• Download the latest x86_64 zip from the GitHub Releases page ↗
• Extract to a permanent folder — note the included direwolf.conf
• Run direwolf.exe once to list audio devices — note the numbers next to your soundcard interface
• Set audio levels: press Win+R → mmsys.cpl → Playback → your device → Levels → ~50%
• Find your PTT COM port: Win+R → devmgmt.msc → Ports → note COM#

The key directives to edit in direwolf.conf:

• Download soundmodemXXX.zip from uz7.ho.ua/packetradio.htm ↗
• Extract to a folder (e.g. C:\soundmodem) — no installer needed
• Run soundmodem.exe — allow firewall access when prompted
• Settings are stored in soundmodem.ini in the same folder — created on first run
• The app creates a system tray icon when running

Go to Settings → Devices:

• Set Output Device and Input Device to your soundcard interface (e.g. SignaLink USB, DigiRig, radio's built-in USB audio)
• For PTT Port: set to NONE if using VOX or SignaLink; set to your COM port for hardware PTT
• For CAT PTT (e.g. IC-7300): click Advanced PTT Settings → select radio manufacturer and COM port
• Enable KISS Server Port (default 8100) — required for Winlink and BPQ connections
• Leave AGWPE Server Port unchecked unless your application requires it
• Click OK → dismiss the restart warning → restart SoundModem

Go to Settings → Modems:

• In Winlink Express, open a Packet Winlink session
• Set TNC type to KISS, address localhost, port 8100
• Select ACKMODE (use NORMAL for Dire Wolf)
• If you see "KISS Server Port Busy" — close all SoundModem instances and restart one
• Update available Winlink channels monthly via the Channels menu

Unlike conventional HF communications where the antenna aims toward the horizon for long-distance skip, NVIS antennas are mounted low to the ground — between 1/20 and 1/4 wavelength high — so that most RF energy radiates nearly vertically.

• RF travels nearly straight up and strikes the ionosphere at a steep (high) angle of incidence
• The ionosphere (primarily the F layer) refracts the signal back toward Earth at similarly steep angles
• The result is omnidirectional coverage within a radius of roughly 50–650 km (30–400 miles)
• There is no skip zone — the signal fills in the area around the transmitting station uniformly
• Physical obstructions (mountains, buildings) are not an issue because the signal travels over them vertically
• Direction finding of NVIS transmitters is significantly harder than ground-wave sources

• Horizontal half-wave dipole — simplest and most effective; orient in any direction (NVIS azimuth pattern is near-omnidirectional)
• Inverted-V dipole — apex slightly higher than optimal but acceptable; easier to deploy with one center support
• Horizontal loop — excellent NVIS antenna; fed with ladder line and a tuner; covers multiple bands
• End-fed half-wave (EFHW) — 64-ft EFHW at low height provides NVIS on 40m, 20m, 15m without a tuner; practical for portable and restricted locations
• T2FD / Butterfly antenna — HOA-friendly; nearly invisible; wideband operation
• AS-2259/GR military antenna — classic NVIS design; two V-shaped dipoles; widely documented

Defines VARA HF as an External driver port in BPQ32/LinBPQ. VARA must be running (or BPQ can launch it via PATH) before connects are possible. PTT is handled by VARA itself via CAT/CI-V — BPQ does not key the radio directly on VARA ports.

Working pair from WQ6N, confirmed on HF via Dire Wolf serial pseudo-TTY to LinBPQ. The 300 baud tones (2130/2230 Hz) are the long-established standard for HF AX.25 packet on 40m and 20m.

Standard VHF packet node port using Dire Wolf over TCP KISS. Based on working configs from KM4ACK (Winlink RMS) and KN4MKB (node + BBS). Start Dire Wolf before BPQ32 — BPQ will connect to the KISS port on startup.

IL2P adds Reed-Solomon forward error correction to AX.25 packet, improving reliability especially above 1200 baud. Created by Nino Carrillo KK4HEJ. The Dire Wolf dev build is the reference open-source implementation and requires Hamlib to be built from source first if you want CAT PTT support.

Key BPQ port parameters and recommended values by mode. HF and VHF have very different timing requirements — using VHF defaults on HF is the single most common cause of failed HF packet connections.