IC-705 USB Serial Backend Setup (macOS)

This guide shows how to control the IC-705 via USB serial CI-V + USB audio devices instead of the default LAN backend.

Why Use the Serial Backend?

• No network required — direct USB connection
• Simpler setup — no IP config, username, or password
• Field operation — works without WiFi/Ethernet
• Portable operation — ideal for IC-705's portable/QRP use case

Hardware Requirements

• IC-705 portable transceiver (HF/VHF/UHF)
• micro-USB cable (the IC-705 has a [microUSB] port)
• macOS computer

Radio Configuration

The IC-705 CI-V Reference Guide (p.2) says to set the radio's CI-V address, data communication speed and transceive function in Set mode, and refers to the IC-705 instruction manual for those settings.

Two USB serial ports

Over USB the IC-705 presents two serial ports. CI-V uses the first one, which Icom's USB driver names "IC-705 Serial Port A (CI-V)".

Recommended Radio Settings

Setting	Value	Why
CI-V Address	0xA4 (IC-705 default)	RigPlane reads it from the IC-705 profile (--model IC-705)

Baud Rate

• 115200 baud is recommended for scope/waterfall capability
• Below 115200, scope/waterfall is disabled by a guardrail due to high packet rate

IC-705 Single Receiver

The IC-705 has a single receiver, unlike the IC-7610's dual receiver. The library automatically enforces this via the IC-705 profile — operations on receiver=1 will fail with CommandError.

macOS Setup

1. Install rigplane

# Core install — includes serial CI-V (pyserial), USB audio RX/TX,
# audio-device listing (sounddevice + numpy + opuslib).
pip install rigplane

Note

Since v0.19 the audio-bridge stack (sounddevice, numpy, opuslib) is part of the core install. The legacy [bridge] and [audio] extras still resolve but are now no-op aliases.

2. Connect the Radio

1. Power on the IC-705
2. Connect the micro-USB cable from the Mac to the IC-705 [microUSB] port
3. Wait ~5 seconds for macOS to enumerate the device

3. Find the Serial Device

# List serial devices
ls -l /dev/cu.*

You can also use rigplane discover --serial-only to list USB serial candidates and identify likely supported radios:

rigplane discover --serial-only

The examples below use /dev/cu.usbserial-IC705123; replace it with the IC-705's CI-V port.

4. Find USB Audio Devices

# List available audio devices
rigplane --list-audio-devices

Audio-device listing requires sounddevice, which ships with the core install since v0.19 (pip install rigplane).

An Icom radio's USB audio device is named USB Audio CODEC. The serial backend picks the audio device automatically when --rx-device and --tx-device are not given.

Usage Examples

CLI: Basic Control

# Read status over USB serial
rigplane --backend serial --serial-port /dev/cu.usbserial-IC705123 \
  --model IC-705 --serial-baud 115200 status

# Set the frequency and mode
rigplane --backend serial --serial-port /dev/cu.usbserial-IC705123 \
  --model IC-705 --serial-baud 115200 freq 14074000
rigplane --backend serial --serial-port /dev/cu.usbserial-IC705123 \
  --model IC-705 --serial-baud 115200 mode USB

Python: Async API

import asyncio
from rigplane.backends.factory import create_radio
from rigplane.backends.config import SerialBackendConfig

async def main():
    # Create IC-705 serial backend
    config = SerialBackendConfig(
        device="/dev/cu.usbserial-IC705123",
        model="IC-705",
        baudrate=115200,
        rx_device="USB Audio CODEC",  # Optional
        tx_device="USB Audio CODEC",  # Optional
    )

    radio = create_radio(config)

    async with radio:
        # Get frequency
        freq = await radio.get_freq()
        print(f"Frequency: {freq} Hz")

        # Set frequency (14.074 MHz USB for FT8)
        await radio.set_freq(14_074_000)
        await radio.set_mode("USB")

        # Get mode
        mode, filt = await radio.get_mode()
        print(f"Mode: {mode}, Filter: {filt}")

        # Note: IC-705 has single receiver only
        # receiver=1 operations will fail

asyncio.run(main())

Web UI

# Start web server with IC-705 serial backend
rigplane --backend serial --serial-port /dev/cu.usbserial-IC705123 \
  --model IC-705 --serial-baud 115200 \
  web

# Open browser to http://localhost:8080

The web UI provides: - Frequency/mode control - VFO select/swap - Scope/waterfall display - Audio bridge (browser → radio TX, radio RX → browser) - PTT control - Memory/filter/settings panels

rigctld (Hamlib Compatibility)

# Start rigctld server with IC-705 serial backend
rigplane --backend serial --serial-port /dev/cu.usbserial-IC705123 \
  --model IC-705 --serial-baud 115200 \
  serve --port 4532

# Test with rigctl client
rigctl -m 2 -r localhost:4532 f  # Get frequency
rigctl -m 2 -r localhost:4532 F 14074000  # Set frequency

Troubleshooting

Serial Device Not Found

# Check if USB device enumerated
system_profiler SPUSBDataType | grep -A 10 "IC-705"

# Check for any serial devices
ls -l /dev/cu.*

Solutions: - Verify the micro-USB cable is data-capable (not charge-only) - Try a different USB port on your Mac - Power cycle the IC-705 and wait for enumeration - Check macOS System Settings → Privacy & Security → USB permissions

CI-V Commands Failing

Symptoms: Connection succeeds but commands timeout or return NAK

Solutions: 1. Check CI-V baud rate matches radio setting (default: 115200) 2. Verify CI-V address is 0xA4 (IC-705 default) 3. Check USB cable integrity

USB Audio Not Working

Symptoms: CI-V control works but no audio in browser/WSJT-X

Solutions: - Make sure you're on rigplane v0.19+ (audio deps ship with the core install; for older versions run pip install 'rigplane[bridge]') - Check audio device names with rigplane --list-audio-devices - macOS may require microphone/audio permissions for the terminal app

Scope/Waterfall Disabled

Symptoms: enable_scope() raises error about baud rate

Solutions: - IC-705 requires 115200 baud for scope capability - Lower baud rates (19200, 9600) will trigger the guardrail - Set --serial-baud 115200 or baudrate=115200 in config - Override the guardrail with ICOM_SERIAL_SCOPE_ALLOW_LOW_BAUD=1 or allow_low_baud_scope=True (not recommended)

Single Receiver Errors

Symptoms: CommandError: … does not support receiver=1 for profile IC-705 (receivers=1)

This is expected behavior — IC-705 has a single receiver (receiver=0 only). The dual-receiver APIs inherited from CoreRadio will fail for receiver=1 operations. Use receiver=0 (or omit the parameter, as 0 is the default).

Capability Matrix: IC-705 vs IC-7610

Feature	IC-705	IC-7610	Notes
Receiver count	1	2	IC-705 single receiver only
Command 29 (sub RX)	❌ No	✅ Yes
CI-V Address	0xA4	0x98	From the --model profile
Baud rates	115200 recommended	115200 recommended	Lower rates disable scope
Audio codec	PCM 1ch 16bit	PCM 1ch/2ch 16bit
Scope	Single stream	Dual stream	IC-705 single receiver = single scope
USB connector	micro-USB	USB-B	Different cables
Portable	✅ Yes (QRP, battery)	❌ No (base station)	IC-705 field-optimized

Backend Comparison: LAN vs Serial

	LAN (UDP)	Serial (USB)
Connection	WiFi	USB cable
Setup	IP address, username, password, --model IC-705	Serial port, --model IC-705
Field operation	Requires network	Direct connection
Audio	Over the LAN link	USB audio devices
Scope	UDP stream	USB serial stream

See Also

• IC-7610 USB Setup — Similar setup for base station model
• Radio Protocol — Backend abstraction details
• Troubleshooting — Common issues and solutions
• Backend Capabilities — Full capability matrix

Validation Status

Not yet validated on 3.0

The IC-705 is community-validated on RigPlane 2.x over WiFi. It has not yet been validated on 3.0.

Get the Packaged Desktop App

Prefer a packaged desktop app?

This guide covers the open-source rigplane Python library. If you want a polished desktop application with a GUI for IC-705 control on macOS and Linux, check out RigPlane Pro.

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