Yaesu System Fusion

System Fusion is Yaesu’s implementation of Digital Amateur Radio, utilizing C4FM 4-level FSK Technology to transmit digital voice and data over the Amateur radio bands. In the early 2000’s GMSK emerged in the Amateur radio market as the dominant digital mode, however in 2013 Yaesu introduced “System Fusion” which quickly became a popular format in Amateur radio because of quality, reliability and enhanced performance in a wide range of environments.

Digital Communication modes have gained popularity over the years in the market because of superior performance in environments with interference, noise and other contributing factors that degrade the quality of a standard FM Analog signal. Narrower bandwidth and the need for increased spectrum have led to the development of digital communications technology, which has been widely adopted in the Public safety and private business sectors that use two-way radio technology. Unlike it’s commercial counterpart, System Fusion is an Amateur Friendly Digital Operating mode, straying away from some of the design considerations that make commercial solutions less appealing and more difficult for Amateur Radio Operators, providing a simpler interface and features that meet the demands and needs of the Amateur enthusiast specifically.


GB7CH automatically senses incoming Yaesu fusion traffic and will switch modes after a few seconds and allow incoming RF communications from a suitably configured Fusion radio. Following the QSO, the repeater will keep listening for up to 20 minutes to the Fusion network on the last selected Room unless the user sends a disconnect code. It will then drop the group and revert back to its static DMR talkgroup. If you have finished using the repeater, please disconnect from the room you were using

Some of the advanced YSF features are not available on GB7CH as they are dependant on the repeater being a Yeasu repeater. These features are noted with: ‘Repeater Dependant’.

Below you will find more information on this marvelous new technology, and how it can meet every operators demand and needs for a clear and simple Digital Experience.Check this Yaesu demonstration video out

The Four Operating Modes of System Fusion

V/D (Digital Narrow) – Voice+Digital or “V/D” mode
Voice FR (VW) Mode – Utilizes all available bandwidth for high-fidelity voice operation, providing the most crystal clear of voice communications.

Highspeed Data
Transfer data such as images or text messages at full rate with speeds up to 9600 Bits-per-second

Analog FM Mode (Repeater Dependant)
Maintains backwards compatibility with existing Analog FM Equipment, allowing a wide range of users to experiment with System Fusion Digital.

Analogue operation is available on dedicated YSF repeaters, but not this MMDVM repeater sadly.

Automatic Mode Select – Complete Digital Co-existence (Repeater Dependant)

On compatible repeaters (Not this MMDVM Repeater) This function instantly recognizes whether the received signal is C4FM digital or conventional FM. The communication mode automatically switches to match the received mode. Even if a digital signal is being used, you can switch to FM communication if radio signals are received from a FM station. This function enables stress-free operation by removing the need to manually switch the communication method each time.
AMS function breaks down into the following operating modes that are fully selectable by the radio user:

  • AUTO: The both RX/ TX mode is automatically selected from one of the four operating modes (DN, VW, DW and FM) to match the characteristics of the received signal. This is the current AMS operation.
  • TX MANUAL: The both RX/ TX mode is automatically selected from four operating modes to match the characteristics of the received signal. And if desired to change the TX mode, by pressing the Microphone PTT switch momentarily, the TX mode switch between DN and FM modes.
  • TX FM FIXED: The RX mode is automatically selected from one of the four operating modes, but the TX mode is fixed to FM.
  • TX DN FIXED: The RX mode is automatically selected from one of the four operating modes, but the TX mode is fixed to the ‘DN’ (Digital Voice Narrow) mode.
  • TX VW FIXED: The RX mode is automatically selected from one of the four operating modes, but the TX mode is fixed to the ‘VW’ (Digital Voice Wide) mode.

Enhanced Communication Functions of System Fusion

Yaesu incorporated a suite of features within the System Fusion product line that are designed specifically for Amateur Radio Use. These features allow the operator to transmit High quality digital voice simultaneously along with Digital Data, and a High Rate (Data FR Mode) dedicated Digital Data mode that provides a method of transmitting Images, Text message and Telemetry Data at a high rate of speed.

Group Monitor (GM) (Repeater Dependant)

Digital Group Monitor automatically checks whether users within a communication group are in or out of range, and displays information such as distance and orientation on the screen of the client radio for up to 24 Stations.

Each individual group can share Text and Picture messages between themselves, allowing intelligent control of how content is distributed amongst a large operating group.

Group Monitor is almost an invaluable feature when an operator or group of operators needs to track resources, such as in an emergency communication operation. Resources can easily be tracked and controlled, letting operators know when they are going to fall out of range and may need to return to the coverage area, or providing invaluable telemetry data for locating and tracking individual operators.

Snapshot Function (Picture Messaging)

By simply connecting the optional MH-85A11U Speaker Microphone with Camera, an operator can quickly take advantage of the high speed data functions of any System Fusion C4FM radio and can easily transmit images to other C4FM users.

Image data which sent from a group member is displayed on the full-color screen of the FTM-400DR or Monochromatic display of the FT2DR. This image data also retains a time record and the GPS location data of the snapshot. It is easy to navigate to that pictured location by using back track function. In addition, you can observe on the screen whether the transmitted data was successfully received by the member station. The snapshot image or received data is stored in a high capacity micro SD card, and you can recall and send that image data from the SD card anytime. The pictures and data files may be easily viewed and edited by using a personal computer by simply inserting the SD Card into any SD Card reader.

Smart Navigation Functions/Backtrack Function

The Smart/Real-time navigation function enables location checking at any time. In digital V/D mode, information such as position data is transmitted together with voice signals so the distance and direction to the other stations can be displayed in real-time while communicating with them.
The Backtrack Function enables navigation to a registered location at the touch of a button. When hiking or camping, simply register your starting point or campsite before departure, and the distance and orientation from the current location are displayed on the screen.

Text Messaging

Text messaging could not be simpler, with direct entry via T9 Text input or the On Screen Keyboard (FTM-400), messages can be sent quickly to an individual operator or group of operators (GM Mode).