Yaesu System Fusion, C4FM & WIRES-X
A detailed introduction to Yaesu digital voice, Fusion repeaters, WIRES-X rooms, hotspots and recommended radio settings.
Understanding the Three Main Components
C4FM, System Fusion and WIRES-X are related, but they are not interchangeable terms. Each describes a different part of Yaesu's digital amateur radio system.
C4FM
C4FM is the digital modulation and voice format transmitted by compatible Yaesu radios.
System Fusion
System Fusion is Yaesu's complete radio and repeater system, allowing compatible repeaters to support digital C4FM and conventional analog FM operation.
WIRES-X
WIRES-X is Yaesu's Internet-linked network. It connects nodes, repeaters and rooms so operators in different locations can communicate.
What Is C4FM?
C4FM stands for Continuous 4-Level Frequency Modulation. In normal operation, it is simply the digital voice mode used by Yaesu System Fusion radios.
DN — Digital Narrow
DN is the most commonly used Fusion mode. It divides the available digital bandwidth between voice and data.
- Digital voice audio
- Callsign information
- GPS location data
- Radio identification
- Text and digital data features
VW — Voice Wide
VW devotes more of the digital signal to voice audio. It may sound fuller under strong signal conditions, but it provides fewer data capabilities.
- Higher voice-data allocation
- No standard GPS data transmission
- Less commonly supported by linked systems
- Best used only when specifically desired
FM — Analog Operation
FM is standard analog frequency modulation. It is used for traditional repeaters, analog simplex channels and stations that do not support C4FM.
- Conventional analog voice
- CTCSS or DCS tones when required
- Compatible with non-Fusion analog radios
AMS — Automatic Mode Select
AMS allows a Fusion radio or repeater to recognize whether an incoming signal is analog FM or digital C4FM.
- Automatically receives analog or digital signals
- Useful on mixed-mode Fusion repeaters
- Transmit behavior may depend on radio settings
What Is Yaesu System Fusion?
System Fusion is Yaesu's digital amateur radio ecosystem. It includes compatible radios, DR-series repeaters, C4FM digital operation and optional Internet linking through WIRES-X.
Digital-Only Repeater
The repeater operates only in C4FM digital mode. Your radio must transmit in DN or another supported C4FM mode.
Analog-Only Repeater
The repeater operates as a conventional analog FM repeater, even if the hardware is capable of Fusion operation.
Automatic Mixed Mode
The repeater detects analog or digital signals and repeats them in the received mode. Analog and digital users normally communicate separately.
How WIRES-X Works
WIRES-X connects compatible nodes and repeaters through the Internet. An operator accesses a local node and then connects that node to a selected WIRES-X room.
WIRES-X Node
A node is a physical Internet-connected station. It may use a Fusion repeater, a dedicated node radio or a compatible personal digital node configuration.
- Has a unique node identification number
- Connects RF users to the Internet
- Can connect to a WIRES-X room
- May be operated by a club or individual
WIRES-X Room
A room is a virtual meeting place. Multiple nodes can connect to the same room, allowing operators in different locations to hear and talk with one another.
- Has a room name and identification number
- May cover a club, region, state or worldwide audience
- Can contain many connected nodes
- May have specific operating rules
Common Room Functions
Search by Room Name
Enter part of a room name and request a matching list from the node.
Most Active Rooms
Display a list of rooms currently showing higher network activity.
Previously Connected
Reconnect to rooms that the node or radio has recently used, depending on the radio and node configuration.
How to Set Up a Radio for Fusion and WIRES-X
The exact menu names vary by radio model, but the following programming sequence applies to most Yaesu Fusion radios.
Enter Your Amateur Radio Callsign
Program your FCC-issued callsign into the radio's digital callsign or My Callsign setting. The radio includes this information in C4FM transmissions.
Example: KO6OFK
Program the Repeater Output Frequency
Enter the frequency you listen to. This is normally listed as the repeater output frequency.
Example: 442.650 MHz
Set the Correct Repeater Offset
Configure the proper shift direction and offset amount. Most amateur 70-centimeter repeaters use a 5 MHz offset, but the correct setting must match the individual repeater.
Example: +5.000 MHz
Select the Operating Mode
Use DN for a digital-only channel or AMS when the repeater supports both analog and digital operation.
Program Analog Tones Only When Required
A digital C4FM transmission normally does not use an analog CTCSS tone. However, some mixed-mode repeaters use a CTCSS tone for analog access.
Set DG-ID
Unless the repeater owner specifies a different value, begin with both transmit and receive DG-ID set to 00.
Save the Channel to Memory
Store the frequency, offset, mode, tone and DG-ID settings in a named memory channel.
Example name: LOCAL FUSION
Test Local Repeater Access First
Before attempting WIRES-X control, make a normal digital transmission and verify that the repeater receives your signal.
Enter WIRES-X Control Mode
Use the radio's X, DX or WIRES-X control function. The radio will transmit a digital request to the node and wait for node information.
Select or Search for a Room
Choose a room from the available list, search by room name or enter a known room identification number when supported.
Allow Time for the Connection
Wait for the node to confirm that the requested room is connected. Do not immediately transmit over the connection announcement.
Disconnect When Appropriate
When local policy permits user-controlled linking, return the node to its normal room or disconnect it when finished.
Accessing WIRES-X on Common Yaesu Radios
Button labels and menu steps may vary with firmware revisions. Refer to the radio's advanced or WIRES-X operating manual for the complete model-specific procedure.
Handheld Operation
Tune to the Fusion node frequency and use the radio's X control to enter WIRES-X mode.
- Confirm the radio is transmitting in DN
- Press or hold the X key as specified by the manual
- Wait for the node information display
- Select a room from the touchscreen menu
Mobile Operation
Tune to the node or repeater and use the radio's DX or WIRES-X function.
- Select the correct operating band
- Confirm the memory channel is set to DN or AMS
- Open the WIRES-X control screen
- Request the desired room
Touchscreen Mobile Operation
Use the touchscreen WIRES-X control function after tuning to a compatible node frequency.
- Verify the active VFO or memory channel
- Enter WIRES-X mode
- Wait for the node response
- Search or select a room
Understanding DG-ID
DG-ID is a digital group identification setting used by System Fusion radios and repeaters. It can limit which digital signals open a radio's digital squelch or access a configured repeater function.
Transmit DG-ID
The transmit DG-ID is included in your outgoing C4FM signal. A repeater or receiving radio may be configured to respond only to selected DG-ID values.
Receive DG-ID
The receive DG-ID can filter incoming C4FM signals. Depending on the radio configuration, only signals matching the selected DG-ID may open the speaker.
WIRES-X, YSF Reflectors and Hotspots
A personal hotspot can carry C4FM audio over the Internet, but a YSF hotspot connection is not automatically the same thing as Yaesu's official WIRES-X network.
| Feature | WIRES-X | YSF Hotspot Network |
|---|---|---|
| Network Type | Official Yaesu network | Community-developed reflector network |
| Connection Destination | WIRES-X rooms and nodes | YSF reflectors or linked gateways |
| Typical Hardware | Yaesu node radio, repeater or approved node setup | Personal hotspot running WPSD or Pi-Star |
| Radio Air Interface | C4FM | C4FM |
| Room Control | WIRES-X commands from compatible radios | Hotspot dashboard, reflector list or radio commands |
| Internet Required | Yes, for linked operation | Yes |
Basic Hotspot Setup
Choose a Simplex Frequency
Select a legal, locally coordinated hotspot frequency that does not interfere with repeaters, satellite allocations, weak-signal activity or other operators.
Configure the Hotspot
Enter your callsign, digital identification information, location, frequency and network settings in WPSD, Pi-Star or the hotspot's management software.
Enable YSF Mode
Enable Yaesu System Fusion or YSF mode and select a startup reflector if desired.
Program the Radio
Create a simplex memory channel using the same hotspot frequency, DN mode, no repeater offset and the required DG-ID.
Use Low Transmit Power
A hotspot is normally only a few feet away. Use the radio's lowest practical power level.
Suggested Radio Settings
| Setting | Recommended Starting Point | Purpose |
|---|---|---|
| Callsign | Enter your issued callsign | Identifies your digital transmissions |
| Digital Voice Mode | DN | Provides voice plus digital data compatibility |
| Mixed-Mode Repeater | AMS when recommended | Receives analog FM or digital C4FM |
| TX DG-ID | 00 | General default unless otherwise specified |
| RX DG-ID | 00 | General default unless otherwise specified |
| GPS | Optional | Allows location data on supported systems |
| Analog CTCSS | Only when published | Required for analog access on certain repeaters |
| Hotspot Power | Lowest practical setting | Prevents unnecessary RF coverage and interference |
Typical WIRES-X Operating Sequence
Listen Before Transmitting
Make sure the local repeater and connected room are not already in use.
Enter WIRES-X Mode
Use the radio's X, DX or WIRES-X control to request node information.
Connect to the Desired Room
Select a permitted room and wait for the node to announce or display the completed connection.
Pause Before Speaking
After pressing push-to-talk, pause briefly before speaking so the repeater and Internet-linked system have time to establish the audio path.
Identify Normally
Use your amateur radio callsign and follow normal FCC identification requirements.
Leave Gaps Between Transmissions
Pause for several seconds between transmissions. This allows other operators to join the conversation and gives linked equipment time to reset.
Return the Node When Finished
Follow the repeater sponsor's policy for disconnecting or returning the node to its normal room.
Common Problems and Corrections
The repeater works in digital voice, but WIRES-X will not connect.
The repeater may not have an active WIRES-X node, may not allow user room changes or may be temporarily disconnected from the Internet. Confirm the node status with the repeater sponsor.
The radio does not display node information.
Confirm that the radio is transmitting in DN, not analog FM. Check the frequency, repeater offset, signal strength, DG-ID and the correct X or DX control procedure.
The repeater receives analog transmissions but not digital.
Verify that the repeater currently supports digital access. Some Fusion-capable repeaters are configured for analog-only operation.
The radio shows AMS but transmits in the wrong mode.
Review the radio's AMS transmit setting. Depending on the model and configuration, the radio may transmit in the last received mode, a fixed selected mode or another configured behavior.
Other digital stations appear on the display, but no audio is heard.
Check the receive DG-ID, digital squelch settings, volume and whether the incoming station is using a compatible voice mode.
The hotspot dashboard shows activity, but the radio does not decode it.
Confirm that the radio and hotspot use exactly the same frequency. Check for frequency offset calibration, incorrect DG-ID, an incompatible mode or excessive RF power overloading the hotspot receiver.
The radio can reach the hotspot only at very close range.
Very short range is normal for many low-power hotspots, but also verify the antenna connection, frequency calibration, hotspot transmit power and radio power level.
Common Beginner Mistakes
- Using analog FM on a digital-only repeater
- Using VW when the network expects DN
- Programming the wrong repeater offset
- Adding an analog tone that is not required
- Changing DG-ID without checking repeater instructions
- Assuming every Fusion repeater has WIRES-X
- Interrupting an active linked conversation
- Failing to pause after pressing push-to-talk
- Using excessive power with a personal hotspot
- Leaving a locally controlled node in an unintended room
Basic Fusion Programming Checklist
- Enter your amateur radio callsign in the radio
- Program the correct repeater output frequency
- Set the proper repeater shift and offset
- Select DN or AMS as required
- Program CTCSS only when specified
- Begin with TX and RX DG-ID set to 00
- Save the settings to a named memory channel
- Test ordinary digital repeater access
- Enter WIRES-X mode only when the node supports it
- Follow the local repeater sponsor's room-control policy
See this page for Suggested Video Links – Yaesu – C4FM Video Links