RadioLog RadioLogby EA5YC
EN ES

RadioLog › Manual › 03 · CAT Control

03 · CAT Control

Connecting your radio, VFO control, modes and relay for external programs

What is CAT?

CAT (Computer Aided Transceiver) allows RadioLog to control your radio from the computer: reading and changing frequency, mode, band and other parameters without touching the physical controls. It also lets WSJT-X and other programs share control without port conflicts.

Configuring the CAT Connection

Go to Settings → CAT to configure the connection with your radio.

CAT section in Settings

Available CAT Backends

BackendRecommended forRequires
Yaesu Direct (relay)Yaesu FT-991A, FTDX10, FT-710, FT-818…Just the USB/serial cable of the radio
Hamlib (rigctld)Icom, Kenwood, Elecraft, Flex, 500+ modelsHamlib installed and rigctld running
OmniRigUsers with OmniRig already configuredOmniRig installed

Yaesu Direct Backend (recommended)

  1. Connect the radio to the PC via USB (the cable included with the radio).
  2. Windows installs drivers automatically. Note the COM port number (e.g. COM3) in Device Manager.
  3. In Settings → CAT: select backend Yaesu Direct.
  4. Choose the radio model, COM port and correct baud rate.
  5. Save the configuration.
  6. Connect from Radio → Connect CAT.
Model and COM port selection in Settings → CAT

Baud rates by Yaesu model

ModelBaud rate
FT-817 / FT-8189600
FT-991 / FT-991A38400
FTDX10 / FTDX10138400
FT-710 AESS38400
FT-DX5000115200
CAT port vs PTT port Modern Yaesu radios with USB create two COM ports: one for CAT and one for PTT/Enhanced. RadioLog uses the CAT port (generally the lower number). The PTT port is used by WSJT-X for RTS in digital modes.

Hamlib Backend (rigctld)

Hamlib supports over 500 radio models. It is the recommended option for Icom, Kenwood, Elecraft, Flex Radio and any non-Yaesu radio.

Installing Hamlib on Windows

  1. Download from github.com/Hamlib/Hamlib/releases the file hamlib-w64-X.X.X.zip.
  2. Extract to C:\Hamlib\.
  3. Check in CMD: C:\Hamlib\bin\rigctld.exe --version

Starting rigctld with your radio

# Icom IC-7300 — COM3, 9600 baud
rigctld -m 3073 -r COM3 -s 9600

# Icom IC-7610 — COM3, 9600 baud
rigctld -m 3078 -r COM3 -s 9600

# Kenwood TS-890S — COM3, 115200 baud
rigctld -m 2044 -r COM3 -s 115200

# Elecraft K3 — COM3, 38400 baud
rigctld -m 2029 -r COM3 -s 38400

# Find your model:
rigctld --list

Configuring RadioLog with Hamlib

  1. Settings → CAT → Backend: Hamlib (rigctld)
  2. Host: localhost | Port: 4532
  3. Make sure rigctld is running before connecting.
  4. Connect from Radio → Connect CAT.

Control Window: Radio → RigControl

Once CAT is connected, open Radio → RigControl for the real-time radio control panel: frequency, mode, VFO-A/B, band and connection status.

RigControl window with VFO and mode in real time

CAT Relay for WSJT-X and Other Programs

When RadioLog is connected to the radio, it automatically acts as a rigctld server (Hamlib NET rigctl) on TCP port 4532. WSJT-X, JTDX, FLDigi and any Hamlib-compatible program can connect to RadioLog without conflict — RadioLog is the sole owner of the serial port.

Configuration in WSJT-X:

Radio configuration in WSJT-X pointing to RadioLog relay

Problem: WSJT-X moves the wrong VFO

Symptom: Changing frequency in WSJT-X moves VFO-B instead of VFO-A (or vice versa).

Cause: On some Yaesu radios (e.g. FTDX10) CAT commands FA/FB don't correspond to the physical VFO-A/B labels.

Solution: Settings → Digital Modes → CAT Relay → ☑ Swap VFO-A/B in relay → Save → Restart RadioLog.

Confirmed on FTDX10 (EA5YC) This setting fixes the problem on the FTDX10 with WSJT-X.
← 02 · Logging QSOs04 · Digital Modes →