Documentation

Introduction

OpenVARA is a web-based VarAC modem and data management system. It runs as a local web server on your network, allowing any browser-equipped device to control one or more ICOM radios over Ethernet using the native ICOM CI-V Ethernet protocol.

Unlike traditional VarAC setups that require a Windows PC with virtual COM ports and audio cables, OpenVARA communicates directly with ICOM's built-in Ethernet interface — no audio interfaces, no serial adapters, no RF-over-USB dongles.

Architecture

OpenVARA runs as a Node.js server on your local network. The web interface communicates with the server over WebSocket for real-time modem status and session data. Each radio instance runs as an independent VarAC modem process, allowing true simultaneous multi-radio operation.

[Browser] ──WebSocket──► [OpenVARA Server]
                                    │
                    ┌───────────────┼───────────────┐
                    ▼               ▼               ▼
              [VarAC HF #1]   [VarAC HF #2]  [VarAC VHF/SAT]
                    │               │               │
                    ▼               ▼               ▼
              [ICOM IC-7300]  [ICOM IC-7610]  [ICOM IC-9700]
              (Ethernet)      (Ethernet)      (Ethernet)

System Requirements

Supported Radios

OpenVARA supports all ICOM radios with built-in Ethernet (LAN) connectivity. The following models have been tested and confirmed working:

Network Setup

Connect your ICOM radio to the same LAN as your OpenVARA server. Assign a static IP to the radio for reliable connections. The default ICOM Ethernet port is 50001.

{
  "radios": [
    {
      "id": "radio-1",
      "name": "IC-7300 HF",
      "model": "IC-7300",
      "host": "192.168.1.100",
      "port": 50001,
      "civAddress": "0x94",
      "username": "admin",
      "password": "admin"
    },
    {
      "id": "radio-2",
      "name": "IC-9700 VHF/UHF",
      "model": "IC-9700",
      "host": "192.168.1.101",
      "port": 50001,
      "civAddress": "0xA2",
      "username": "admin",
      "password": "admin"
    }
  ]
}

CI-V Configuration

On your ICOM radio, navigate to MENU → SET → Connectors → CI-V and configure the following:

APRS Overview

OpenVARA includes a built-in APRS engine that handles packet encoding/decoding, position beaconing, and APRS-IS gateway connectivity. Your ICOM radio transmits and receives APRS packets directly — no TNC hardware required.

Beacon Configuration

{
  "aprs": {
    "callsign": "W1AW-9",
    "ssid": 9,
    "symbol": "/>",
    "comment": "OpenVARA Node",
    "beacon": {
      "enabled": true,
      "intervalMinutes": 10,
      "smartBeaconing": false
    },
    "aprsIs": {
      "enabled": true,
      "server": "rotate.aprs2.net",
      "port": 14580,
      "passcode": 12345
    }
  }
}

Winlink & Pat Overview

OpenVARA exposes a local VarAC modem endpoint that Winlink Express or Pat can connect to. The modem handles all RF communication with your ICOM radio — supporting HF, VHF/UHF, and SAT modes — while Winlink or Pat manages the email session layer.

Session Setup

In Winlink Express or Pat, configure a new VARA HF, VARA FM, or VARA SAT channel and point it to the OpenVARA local endpoint:

Instance Management

Each radio in OpenVARA runs as an independent modem instance with its own port assignment, frequency control, and session state. Instances are defined in config/radios.json and start automatically with the server.

Radio 1 (IC-7300):  Command: 8300  Data: 8301
Radio 2 (IC-7610):  Command: 8302  Data: 8303
Radio 3 (IC-9700):  Command: 8304  Data: 8305
...and so on (increments of 2 per radio)