Foxtech D04 User manual

D04
Multi-link Signal Relay

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Contents
Disclaimer.....................................................................................................................3
Product Introduction....................................................................................................5
Packing List................................................................................................................... 6
Product instructions.....................................................................................................7
Radio Power On and Off.............................................................................................. 9
Status Indicator Instructions......................................................................................10
Ground Unit Indicator.................................................................................10
Receiver Indicator....................................................................................... 11
Ground Unit and PC Communication........................................................................ 12
Wireless network selection and setup...................................................................... 13
WIFI Wireless Network Connection............................................................13
BLE Wireless Network Connection............................................................. 15
Datalink Link Communication Test.............................................................................20
Radio Parameter Configuration................................................................................. 21
Ground Unit Battery Charging................................................................................... 26
Radio Alarm................................................................................................................27
Failsafe Setting........................................................................................................... 28
WiFI Module Parameter Setting................................................................................ 29
BLE Module Parameter Setting...................................................................34
BLE and WIFI Modules are Restored to Factory Settings........................... 36
Check the Radio System Firmware Version............................................................... 37
Firmware Upgrade Steps............................................................................................38
Ground unit Firmware upgrade..................................................................38
Receiver firmware upgrade........................................................................ 41
FAQ............................................................................................................................. 43

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Disclaimer
Thank you for purchasing the D04 Dual Link Radio (hereafter referred to as "D04").
Please use D04 according to local radio regulations. Please read this statement
carefully before using it. Once used, it is deemed to be an endorsement and
acceptance of the entire contents of this statement. Please strictly follow the
instructions to install and use the product. FOXTECH Co., Ltd. will not assume any
legal responsibility for any result or loss caused by improper use, installation,
assembly and modification of the user.
Product Note:
1. D04 is used as the ground end (hereinafter referred to as "ground end") in
conjunction with the sky end R20 (hereinafter referred to as "sky end" or "airborne
end").
2. Built-in 12V battery on the ground (18s battery for 3s), external power input
DC7.4 - 12V (lithium battery 2s - 3s), please supply power to the radio in strict
accordance with the specifications.
3. Be sure to install the antenna before powering up to avoid damage to the circuit.
4. Ensure that the antenna is obstructed during the use of the antenna, without
bending, and as far as possible away from the large metal structural parts, to avoid
communication obstruction due to the above reasons.
5. Do not disassemble or modify it without permission. If you encounter problems
that cannot be solved during installation or use, please contact Huazhiyi or your
agent.
6. Pay attention to keep the proper distance between the electronic devices during
installation to minimize electromagnetic interference between devices.
7. Make sure all connections are securely fastened and all parts are working
properly before use.
8. Please check the surrounding environment before use to ensure that there is no
interference from other 840MHZ-930MHZ equipment, otherwise the radio data
transmission may be seriously affected.

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9. For better service customers, we have been optimizing the product upgrade. The
matching software and firmware of the product will be updated and updated from
time to time. There may be incompatibility between different firmware versions on
the ground and onboard. So please pay attention to check the software firmware
version when using. Please also pay attention to our website to get the latest
software firmware and technical support.
10. The software, firmware, drivers, port conversion tools, etc. involved in this
manual will be updated from time to time on our website. Please visit our website
to download it yourself or contact customer service.

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Product Introduction
The D04 is a multi-link signal relay system that can simultaneously transmit up to
two independent S-BUS data and one serial port data. By using D04 signal relay
The remote control signal can be enhanced and transmitted to the air unit together
with the TTL signal.So D04 Multi-link Signal Relay solves the problem of short
transmission distance of the remote controller and datalink. D04 features small size,
good integration and high sensitivity. The ground unit is integrated with wireless
network module (WIFI or BLE can be selected according to requirements), so users
can connect to RB20W ground unit by wireless network or USB data cable.
The wireless network can reach a stable coverage of 30~50M without interference.
D04 signal relay works in 840MHZ~915HZ frequency band and the maximum
communication distance is up to 30KM.

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Packing List
Main Module
Accessories
Cahrger×1
USB cable×1
Power cable×1
Parameter setting
For ground unit
For parameter
setting
For air unit
（DC:7.4-12V)
For air unit
Ground Unit ×1
Air Unit x 1

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Product instructions
D04 can simultaneously transmit up to two independent S-BUS data and one serial
port data. There are two ways to access the serial port data on the ground. One is
to input directly through the USB data line, and the other is to transmit through the
WIFI or BLE wireless network. When D04 detects the USB data cable insertion, it
uses USB to transmit the serial port data preferentially. When it is detected that the
USB data cable is not inserted, D04 automatically switches to your preset wireless
module (WIFI or BLE) to transmit the serial port data. If your remote control or
receiver does not support S-BUS, you will need to purchase a separate PWM to
S-BUS module.
Ground Unit
1Power indicator and button PWR
24 power indicator 25% ，50%， 75%， 100%
3Config indicator
2 S-BUS signal input，or config type
4Charge port
Support only DC 12.6V input
5Antenna interface

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SMA
6SET button
For parameter setting
7USB port Type-C
For parameter setting or data transmission, not batter charge port
8Data transmission module signal indicator
Indicator RS1 RS2 RS3 is the signal strength indicator. The number of lights indicates the strength of the
signal quality of the high-frequency data transmission module. It can also be used to indicate the type of
wireless network configuration in the configuration mode.
9wireless network connection status indicator nLink
The indicator light indicates that the wireless network is connected or transmitting data, and the indicator is off
indicating that the wireless network is not connected or is not transmitting data.
10 Working status indicator of wireless network nReady
When the indicator is on, the wireless module is working properly and can connect and transfer data.
Ground unit connection
diagram

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Radio Power On and Off
1. After pressing the power button PWR, the power indicator lights up and the four
battery indicator lights start to flash simultaneously.
2. During the period when the battery indicator flashes (about 5S), release the
power button and press and hold the power button again. At this time, the four
battery indicators will light up in the way of the water lamp until the buzzer sounds
long. Indicates that the boot action is complete.
3. The shutdown operation is the same as the startup operation. The flow direction
indication is different from the startup only when the button is pressed for a long
time.

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Status Indicator Instructions
Ground Unit Indicator
Indicator
status
implication
RS1,RS2,RS3 Configuration
mode
RS1 flash，RS2 和 RS3 go out
current wireless mode is WIFI
RS 1and RS2 flash， RS3 go out
current wireless mode is BLE
RS1,RS2,RS3 status before
turned on
RS1 is on，RS2and RS3 go out
current wireless mode is WIFI
RS 1and RS2 are on， RS3 goes out
current wireless mode is BLE
RS1,RS2,RS3working status
RS1,RS2,RS3 are on
High frequency module signal is strong
RS 1and RS2 is on，RS3 go out
High frequency module signal is general
RS1 is on，RS2and RS3 goes out
High frequency module signal is weak
Config
Always being on
In high frequency module config. mode
Go out
SBUS1 and SBUS2 no signal input
One flash a time
SBUS1 has signal input
Two flashes a time
SBUS2 has signal input
Quich flashing
SBUS1 and SBUS2 has signal input
PWR power indicator
flash
Firmware upgrade status in configuration mode
flash， with short continuous sound of
buzzer
Low voltage alarm
Always being on
Radio is powered on，in normal working status
Go out
Radio is powered off
4 power capacity indicator
25% flash， other 3 go out
LOW BATTERY less than 25%
25% flash，other 3 go out
Power during 25%～50%
25% and 50% is on ，other 2go out
Power during 50%～75%
25%、50% and 75% on，100% goes out
during 75%～100%
25%、50%、75%和 100% all are on
Fully charged 100%
All 4 flash， with short continuous
sound of buzzer
High temperature protection status