Yaesu FTDX10 + fldigi Setup Guide

Complete setup for Olivia and other digital modes. The FTDX10 is Yaesu's mid-range performer with dual virtual COM ports and built-in USB audio codec.

Quick Reference

USB ConnectionSingle cable provides dual COM ports + audio
Hamlib Rig Number1042
Baud Rate38400
Audio DeviceUSB Audio Device (FTDX10)
DATA MOD SOURCEREAR
REAR SELECTUSB

1. USB Connection Architecture

The FTDX10 connects via a single USB cable, which provides:

  • Dual Virtual COM Ports (automatically created by drivers)
  • Audio codec for digital mode AF in/out
  • CAT control interface for frequency and mode management

Virtual COM Port Mapping

PortPurposeWindowsLinux
Enhanced COM PortCAT Control, Firmware UpdatesCOM5/dev/ttyUSB0
Standard COM PortPTT Control, CW KeyingCOM6/dev/ttyUSB1

Key Advantage

Unlike older Yaesu transceivers, the FTDX10's USB connection includes a built-in sound device, eliminating the need for separate audio interface hardware.

2. Driver Installation

Windows 11/10

  1. Download CP210x_Universal_Windows_Driver.zip from Yaesu's support page
  2. Unzip to a dedicated folder
  3. Right-click on silabser.inf and select Install
  4. Windows will assign COM5 and COM6
  5. Verify in Device Manager under "Ports (COM & LPT)"

macOS

  1. Download Silicon Labs CP210x VCP driver from Silicon Labs
  2. Recommended version: v6.0.1 or later
  3. Install and restart
  4. Verify: ls -la /dev/cu.SLAB*

Linux

No additional drivers typically required. Most distributions include built-in kernel drivers.

If ports don't appear, verify user is in dialout group:

sudo usermod -aG dialout $USER

3. Radio Configuration

MODE PSK/DATA Settings

SettingValuePurpose
DATA MOD SOURCEREARRoute digital audio from USB
REAR SELECTUSBUse USB audio codec as rear input
RPTTRTSUse RTS handshake for PTT
USB DATA LEVEL50Audio input level (adjust as needed)
RPORT GAIN10USB audio output level
HCUT FREQOFFHigh-cut filter off
LCUT FREQOFFLow-cut filter off

OPERATION SETTING → GENERAL

SettingValue
CAT RATE38400 baud
CAT RTSON

Critical Note

Even with DATA-U mode selected, the front microphone input remains live. Set MIC GAIN = 0 when operating digital modes to prevent stray sounds from transmitting.

4. fldigi Configuration

Option A: Using Hamlib (Direct CAT)

  1. Transceiver dropdown: Select Yaesu FTDX10 or Hamlib Generic
  2. Rig Number: 1042
  3. Port: Select your CAT port (COM5 on Windows, /dev/ttyUSB0 on Linux)
  4. Baud: 38400
  5. Handshake: RTS/CTS (critical for PTT)
  6. Click Initialize

Option B: Using FLRIG (Recommended)

Many operators report better reliability with FLRIG as an intermediary:

  1. Install FLRIG separately
  2. In FLRIG: Set Rig to Yaesu FTDX10, Port: COM5, Baud: 38400
  3. Start FLRIG and verify connection
  4. In fldigi: Transceiver dropdown → Select FLRIG
  5. Click Initialize

Why FLRIG? The FTDX10's CAT implementation has quirks. FLRIG handles USB communication more robustly.

Audio Configuration

  1. Audio Input: Select USB Audio Device (FTDX10)
  2. Audio Output: Same USB Audio Device
  3. Sample Rate: 48000 Hz (most stable)
  4. Click Test to verify signal levels

5. Olivia Configuration

Standard Olivia Modes

ModeBandwidthSpeedUse Case
2000/642 kHzFastestGood conditions
1000/321 kHzMediumNormal conditions
500/16500 HzSlowMarginal conditions
250/8250 HzSlowerPoor conditions
125/4125 HzSlowestVery poor conditions

Default Calling Mode: 32-1000 (1 kHz bandwidth, 32 integration period)

Critical Rule

Both sides of an Olivia QSO must use identical tone spacing and integration period settings. Default (8 Hz / 4 integration) works for calling frequency operations.

6. Common Issues and Troubleshooting

PTT Not Working

  1. Verify radio settings: RPTT = RTS, CAT RTS = ON
  2. Try FLRIG instead of Hamlib
  3. Check PTT method: Use CAT if using Hamlib, NONE if using FLRIG
  4. Verify using Standard COM Port (COM6/ttyUSB1) for PTT
  5. Power cycle radio and USB cable

Audio Not Transmitting

  • Check DATA MOD SOURCE = REAR
  • Verify USB DATA LEVEL is at ~50 (not 0)
  • Select correct USB Audio Device in fldigi
  • Check REAR SELECT = USB
  • Disable mic audio: MIC GAIN = 0

Audio Not Receiving

  • Verify audio input device in fldigi
  • Check AF GAIN knob (20-40% typical)
  • Check RPORT GAIN (start at 10, increase to 15-20 if weak)
  • Verify tuned to active frequency in DATA-U mode
  • Linux: Verify user is in audio group

7. Official Documentation

Pre-Flight Checklist

  1. USB drivers installed, two COM ports visible
  2. DATA MOD SOURCE = REAR, REAR SELECT = USB, RPPT = RTS
  3. CAT RATE = 38400, CAT RTS = ON
  4. MIC GAIN = 0
  5. fldigi: Hamlib 1042 or FLRIG connected
  6. fldigi: USB Audio Device selected for input/output
  7. Radio in DATA-U mode
  8. Waterfall shows receive signals
  9. PTT keys radio when TX clicked
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