Getting Started - The Basics

For most digital soundcard stations, you need three basic components working together.

[Transceiver] + [Interface] + [Computer]

These three components form the foundation of any digital soundcard station.

The Transceiver

Any SSB-capable amateur radio transceiver can be used for digital modes. Most HF activity uses Upper Sideband (USB), though FM digital modes are popular on VHF/UHF.

Key Points

  • Power: Run at 50% or less of rated power for digital modes (high duty cycle)
  • Stability: Frequency stability matters for some modes, but Olivia is forgiving
  • Bands: All amateur bands with RTTY/DATA privileges allow digital operation

Modern Radios with Built-In USB Audio

Many modern transceivers have integrated USB audio - no external interface needed!

  • Icom: IC-7300, IC-7610, IC-705
  • Yaesu: FT-991A, FTDX10, FT-710
  • Kenwood: TS-890S, TS-590SG
  • Elecraft: K4 (KX3 requires external soundcard)

See our complete radio setup guides →

The Interface

The interface connects your radio to your computer, handling audio routing and transmit keying (PTT).

What an Interface Does

  1. RX Audio: Takes audio from the radio and sends it to the computer for decoding
  2. TX Audio: Takes computer-generated audio tones and sends them to the radio for transmission
  3. PTT Control: Tells the radio when to transmit
  4. Isolation: Keeps RF out of your computer (prevents crashes and interference)

Option 1: Built-In USB

Modern radios with USB audio need only a single USB cable. Audio and CAT control travel over the same connection.

Recommended for: IC-7300, FT-991A, TS-890S, K4

Option 2: External Interface

For older radios or those without USB audio:

  • SignaLink USB (~$120) - Popular, reliable, built-in soundcard
  • Digirig Mobile (~$50) - Compact, modern alternative
  • DIY Interface - Isolate audio, add VOX or serial PTT

Use DATA Port When Available

If your radio has both a microphone jack and a DATA port, always use the DATA port. This keeps your mic connected for voice operation and provides cleaner audio paths.

The Computer

Operating System

fldigi runs on:

  • Windows 10, 11 (XP through 8.1 with older versions)
  • macOS 10.12+ (Intel and Apple Silicon)
  • Linux Most distributions

Hardware Requirements

  • CPU: 1 GHz+ recommended (Olivia is CPU-intensive)
  • RAM: 2 GB minimum
  • Ports: USB for modern radios, serial for legacy interfaces

Tip: Avoid heavy multitasking while operating Olivia

Software Setup (Windows 11)

Step 1: Install Drivers

Most modern radios use built-in Windows drivers. If not detected automatically:

  • Icom: Uses standard USB drivers (auto-installed)
  • Yaesu: CP210x (FT-991A) or FTDI (FT-710) - usually auto-installed
  • Kenwood: CP210x - usually auto-installed
  • Elecraft: FTDI - usually auto-installed

Check Device Manager to verify your COM port appears under "Ports (COM & LPT)".

Step 2: Install fldigi

  1. Download from sourceforge.net/projects/fldigi
  2. Run the installer
  3. Complete the initial setup wizard (callsign, name, QTH)

Step 3: Configure Audio

  1. Open fldigi → Configure → Sound Card
  2. Select your radio's USB Audio Codec for both Capture and Playback
  3. If using an external interface like SignaLink, select that device instead

Step 4: Configure Rig Control

  1. Open fldigi → Configure → Rig
  2. Select Hamlib or RigCAT (see radio guides)
  3. Choose your radio model and COM port
  4. Set the correct baud rate (varies by radio)
  5. Click Initialize to test

Step 5: Configure PTT

For most modern radios with USB control:

  1. Go to Configure → Rig → PTT section
  2. Select CAT or RTS depending on your radio
  3. Test by clicking the TX button in fldigi - your radio should key

Next Steps

Configure Olivia

Learn how to set up Olivia mode specifically - tune margin, integration period, and mode selection.

Olivia Setup →

Radio-Specific Guide

Get detailed setup instructions for your specific transceiver model.

Radio Guides →