DIVIMATH HDZero Race V3 User manual

1
HDZero Video Transmitters
Whoop Whoop Lite Race V1 Race V2
Race V3 Freestyle V1 Freestyle V2
What is HDZero?
PUSH YOUR SKILLS TO THE LIMIT
HDZero offers industry-leading low latency, giving you more time to react and the best possible chance of hitting
that next gap. With its smooth, consistent FPV video feed, you’ll experience the same locked-in feeling you get
with analog video–but with the clarity of HD.
MAKE IT AN EVENT
HDZero supports the standard 5.8ghz video channels, meaning you can have up to 8 simultaneous pilots flying
either full-quality HDZero or analog video. When you’re ready to take a break and spectate, you can tune in to any
channel and view the pilot’s feed with no loss of quality, giving you the same feeling of being in the air yourself.
UPGRADE YOUR FLEET
From 1S whoops to long-range wings, HDZero offers a variety of VTX and camera options to suit every build. You
may even be able to use the gear you already have–the HDZero receiver will work with any FPV goggle with an
HDMI input. HDZero can grow with your needs and fit perfectly into your preferred FPV craft.
RAPIDLY EVOLVING SYSTEM
HDZero is rapidly evolving. Please always use the latest firmware that is located at www.hd-zero.com/document.

2
Contents
What is HDZero? 1
HDZero VTXes 3
Powering the VTX: BEC or VBAT 4
Mounting Considerations 5
HDZero Whoop Video Transmitter (EOL) 6
HDZero Whoop Lite Video Transmitter 7
HDZero Race V1 Video Transmitter (EOL) 8
HDZero Race V2 Video Transmitter (EOL) 9
HDZero Race V3 Video Transmitter 10
HDZero Freestyle V1 Video Transmitter(EOL) 11
HDZero Freestyle V2 Video Transmitter 13
HDZero VTX Installation Guide 14
HDZero Firmware Update Guide 15
VTX update Guide 16
VRX update Guide 16
Steps to update HDZero VRX 16
Steps to update Shark Byte VRX 16
Steps to flush VRX in case of not booting up 16
Setup and Getting Started 18
OSD Setup 18
1. Prerequisition 18
2. Update firmware VTX and VRX 18
3. Solder/Connect VTX UART to an available UART on your FC board 18
4. Flight controller Configuration (Use Betaflight as example) 18
5. Restart/Connect Flight controller Configuration (Use Betaflight as example) 18
Stick Movement 20
Using VTX Menu (Applicable to all VTXes) 21
Unlock RF Power Limit 23
Unlock Low Band 23
Using SmartAudio (Not recommend) 23
Help and Troubleshooting 24
FAQ 24
Trouble Shooting 24

1
HDZero VTXes
VTX Name
Whoop
(EOL)
Whoop Lite
Race V1
(EOL)
Race V2
(EOL)
Race V3
Freestyle V1
(EOL)
Freestyle V2
Dimension
(mm x mm)
32x32
32x32
27x45
34x34
28x32
40x40
29x30
Mounting Pattern
25.5x25.5
25.5x25.5
20x20
20x20
20x20
30x30
20x20
M2
M2 (Soft)
M4(Soft)
M4(Soft)
M4(Soft)
M3(Soft)
M2
Weight
5.3grams
4.5grams
7grams
6grams
5.5grams
28grams
22.3grams
Power Input
7V-17V (2S-4S)
1S-3S
7V-17V (2S-4S)
7V-17V (2S-4S)
4V-12V (2S-3S)
2S-6S (2rd batch or
later)
7-25V
Power
Consumption
5~6W
5~6W
5~6W
5~6W
5~6W
6~15W
6~15W
RF Power Output
25mW,200m
W
25mW,200m
W
25mW,200m
W
25mW,200m
W
25mW,200m
W
25mW,200mW
(500mW,
1W if with HAM
license
25mW,200mW
(500mW,
1W if with HAM
license
Secured U.FL
No
Yes
Yes
Yes
Yes
Yes
Yes
Antenna Included
Not included
Not included
Not included
Not included
Not included
Polarized(RHCP)
Polarized(RHCP)
Tramp/SmartAudi
o
No
SmartAudio
SmartAudio
SmartAudio
Tramp
SmartAudio
SmartAudio
Application
Whoop
TinyWhoop
Race
Race
Race
Freestyle
Freestyle

2
Caution: UFL Connectors Are Fragile
All HDZero VTXes use an U.FL connector for its smaller footprint and lighter weight. However, it is not a
mechanically strong connector. Treat it as if it’s made of glass. Here are notes for installing and
uninstalling an antenna:
▪Never run a cable from the UFL connector straight off the side of a board. Instead, run the antenna
cable towards the middle of the board, and secure it in one of the following ways:
oHot glue or E6000 glue
▪Avoid using glue on top of the hot components on the board.
▪Preferably, apply glue to the side of the board where the cable leaves the top of the
board.
oKapton tape to secure it to the surface of the VTX
oZip tie it to a nearby standoff
▪Unless you need maximum RF performance or minimum weight, consider a UFL->SMA pigtail for
larger builds. This allows you to thoroughly secure the SMA connector to your aircraft to prevent
movement of the antenna cable.
▪When removing the antenna, go very slowly and pull gently on the antenna so that one side of the
UFL slides off first. There are tools designed to remove/insert UFL connectors from their sockets,
which can help avoid damage to the UFL connector or socket.
Please visit the following link for more information:
https://www.facebook.com/groups/hdzero/permalink/448657693828864/
Powering the VTX: BEC or VBAT
Using a battery eliminator circuit (BEC) is highly recommended to avoid voltage spikes, which can
damage the VTX. Although you can power the VTX directly from the battery (VBAT), a BEC will provide
more consistent power and will help absorb any voltage spikes, protecting your VTX from over-voltage
conditions.
It is important to select a BEC that provides voltage that is within the range of what the VTX accepts, and
that is capable of supplying enough current to power the VTX. Whether you are using a BEC that is built
into your flight controller or a standalone BEC, be sure to check its voltage and current ratings and
compare them to the required voltage and current for your VTX.
All the FCs that include an integrated BEC for DJI VTXes should also work for HDZero VTXes.
To summarize:
▪All HDZero VTXes, except Freestyle V1 Batch 2 VTX or later and Freestyle V2, do not support 6S
VBAT.
▪Check your FC specs to see if you can run your VTX from the FC’s BEC;
▪If not, you could run the VTX from a suitable standalone BEC;
▪If not, solder a capacitor between the +V and Ground on the VTX. Running on VBAT is always the last
choice due to the challenging voltage environment in an aircraft.

3
Mounting Considerations
It is very important to keep some distance between the VTX and ESC/FC boards for the following
reasons:
-The RF portion of VTX is vulnerable to electronic noise caused by ESC/motors;
-The RF signal can be bounced back from surfaces of boards or carbon fiber plates, and fed back
to the power amplifier in the VTX. This will deteriorate the RF signal integrity and could damage
the amplifier.
To avoid these concerns, follow this guidance for mounting the VTX:
▪If the VTX is mounted on the top of the stack, please keep 5mm distance from the top carbon fiber
plates.
▪Avoid mounting the VTX in the middle of the stack.
▪If the VTX is mounted on the bottom of the stack, the VTX needs to be upside down (U.FL socket
faces down) and needs to have a minimum of 5mm distance from the bottom carbon fiber plates.

4
HDZero Whoop Video Transmitter (EOL)
The HDZero Whoop VTX is a digital HD 720p 60fps video transmitter capable of delivering up to 200mW on 5.8GHz.
The power input range is 7V –17V.
Due to the small clearance of mounting holes, make sure the mounting nuts or gummies will not overlap into
the small components around the holes.
This VTX is designed for low-speed whoop application. Compared to the other HDZero VTXes, it is more vulnerable
to be damaged by crash due to: (1) the UFL connector is easily peeled off due to no antenna retention, and (2) it is
not easy for soft mounting. Though the VTX can be mounted on a racing and other high-speed aircraft, it is highly
recommended to consider
HDZero Race (V1 or V2) for
such application.
This VTX does not support
Smart Audio or Tramp
Notes:
1. Read first: General Consideration for VTX Installation
2. Soft mount
3. Pay extra attention not to damage the small components when trying to remove the serrate corner
1
2
3
4
5
6
7
8
GND
7-17V
RX
TX

5
HDZero Whoop Lite Video Transmitter
The HDZero Whoop lite VTX is a digital HD 720p 60fps video transmitter capable of delivering up to 200mW on
5.8GHz.
The power input range is 2.8V –13V.
-This VTX does not have reverse polarity protection circuit, it will be permanently damaged if voltage
input is reversely connected. This is number one failure cause.
-When it is powered by a 5V pad of FC/BEC, make sure that 5V has 1.5A current output.
-When it is powered by an 1S battery directly, note that a rapid throttle up may cause voltage drop below
to 2.8V instantly, and that will cause video drop.
-There is no need for an external capacitor when it connects with FC/BEC or 1S battery. However, it is
strongly suggested to put on a capacitor when powered by a 3S battery.
This VTX has protection cases mounted on both sides. These metal cases are grounded, and to provide protection
from crash. They can be removed for any light weight build for which every gram matters.
This VTX includes M3/M2 gummies for soft mounting, and zip ties for antenna retention. Though the VTX can be
mounted on a racing and other high-speed aircraft, it is highly recommended to consider HDZero Race (V1 or V2)
for such application.
Solder pads:
G
Ground
V
2.8V -13V
RX
FC.TX
TX
FC.RX
SA
FC.SA (TX), Optional
Notes:
1. Read first: General Consideration for VTX Installation
2. This VTX does not support using a keypad to tune channel and RF output power level. It is
designed to work with a flight controller.
1
MIPI Connector
2
Status LEDs
3
Power/UART/SA solder pads
4
u.FL Connector
5
Protection Case
6
Protection case clipper
2
3
4
6
5
1

6
HDZero Race V1 Video Transmitter (EOL)
The HDZero Race VTX is a digital HD 720p 60fps video transmitter capable of delivering up to 200mW on 5.8GHz.
The power input range is 7V –17V.
1
Power/UART Connector
2
FW Update Connector
3
MIPI Connector
4
u.FL Antenna Connector
5
u.FL Antenna Retention Holes
6
Power on LED (red)
7
Status LED (blue)
8
Mounting Holes (20x20 M4)
9
Zip Ties (4x)
10
u.FL Antenna Retention
Screws(4x)/Nut(4x)/Plate
11
Rubber Grommet (M4 to M3 4x)
12
Power/UART harness (20cm) and a
PH2.0 connector (6P)
Power/UAR
T Connector
Cable Color
Connected with
Ground
Black
Ground
Power
7-17V
Power
T1
Green
FC.RX
R1
Yellow
FC.TX
T2
White
DO NOT CONNECT
R2/SA
Gray
FC.SA (TX)
Connection between Race V1 VTX and FC
There are 3 methods to connect the VTX and flight controller:
-Plug the included harness, cut the cables to
-appropriate length, and solder them on FC
-Use solder pads on the back of the connector
-For FCs having BEC and UART connector, install harness to the included PH2.0 connector (Shown
above), and connect the harness with FC without any soldering.
Warning: Check that pinout matches the FC pinout before installing to be safe if plugging directly.
Mounting an u.FL antenna or pigtail
There are 2 methods to mount antenna on VTX:
-Use included retention screws, nuts and plate;
-Use included zip-ties.

7
HDZero Race V2 Video Transmitter (EOL)
The HDZero Race VTX is a digital HD 720p 60fps video transmitter capable of delivering up to 200mW on 5.8GHz. It
works with the Shark Byte RX5.1 goggle module to transmit video, and with a remote controller to wirelessly
control the parameters for the transmitter and camera.
The power input range is 7V –17V.
1
Power In (G=Ground, V=7-17V)
2
T1/R1 UART Connection to FC
3
T2, Reserved,
R2/SA, SA Pin
4
u.FL Antenna Connector
5
u.FL Antenna Retention Holes
6
MIPI connector
7
MIPI connector retention Holes
8
Firmware Update Connector
9
Power on LED (red)
10
Status LED (blue)
11
u.FL Antenna Retention
Screws/Nut/Plate
12
Rubber Grommet (M4 to M3),
1mm O-Ring
13
Zip ties
14
Connecting wire
15
20x20 M4 mounting holes
Mounting a u.FL antenna or pigtail
There are 2 methods to mount the antenna on VTX:
-Use included retention screws, nuts and plate;
-Use included zip-ties.
Connecting MIPI cable
Use the included zip-tie to secure MIPI cable and
protect MIPI connector.
Notes:
-Read first: General Consideration for VTX Installation
-Make sure to use a wider top plate to fully cover this VTX for protection.
1
2
3
4 5
67
8
910
11
12
14
13
4x 4x 1x
8x 8x
4x
1x
15

8
HDZero Race V3 Video Transmitter
Designed for FPV racing, the HDZero Race V3 VTX is our 3rd generation digital video transmitter. With a voltage
range starting at 4V, it can be powered by the 5V 1.5A regulator of most FC’s or up to 12V for FC’s that include a
HD VTX plug. It is small (28x32x5mm) and light (5.5 grams). With a width of only 28mm, the VTX is now a similar
width to many FC's, which improves durability and reduces weight. The antenna is securely attached with a metal
bar and screws. No soldering needed –just plug the wire harness into a compatible HD-ready FC.
The HDZero Race V3 VTX is designed with durability in mind, rather than weight. It is made with a 1.6mm thick
PCB, in comparison to the 1.0mm PCB used in the Whoop lite VTX. Moreover, it uses more large package size
components for stability consideration. For the smaller components, an additional glue coating is applied to
increase crash protection.
The HDZero Race V3 VTX offers high-quality video in 540p90, 720p60 and 1080p30 resolutions with 25/200mW
switchable power on 5.8GHz.
Connection
The right figure shows the typical connection with
FC supports MSP VTX protocol.
The Race R3 supports direct connect with Ghost
RX via its SA/Tramp port (TBD)
1
VTX-R3 board
2
SmartAudio/Tramp (Optional)
3
Wire harness to connect with FC
Red = BEC 4-12V
Black = GND
White = VTX UART TX (Connect to FC.RX)
Yellow= VTX UART RX (Connect to FC.TX)
4
Rubber Grommet (M4 to M3),
5
Metal bar and screws for securing antenna
12
3
4 5

9
HDZero Freestyle V1 Video Transmitter(EOL)
The HDZero Freestyle V1 VTX offers unprecedented range and performance for the HDZero 5.8GHz
digital FPV system. With its high maximum output power and robust construction, this VTX is perfect for
freestyle and long-range builds.
With a tested maximum range of more than 18 miles, the Freestyle V1 VTX will transmit a digital FPV
feed as far as you’re willing to fly. Not interested in long range? You’ll also see better performance in
urban environments and around obstacles, with none of the color noise or multipath interference issues
of analog video.
1
Secured MIPI Connector
2
Keypad Connector
3
M3 Mounting Hole
4
Secured U.FL Connector
5
FW Update Connector
6
Power/UART Connector
7*
BEC Power in (2S-6S)
8*
BEC Power Out Pad
9
RHCP Antenna
10
Power/UART Harness
*: BEC is included for first Batch only.
*: The 1st batch supports 4S MAX.
Power/UART
Connector
Cable
Color
Connected with
Ground
Black
Ground
Power
Red
Power*
RX
Green
FC.TX
TX
Yellow
FC.RX
SA
Blue
FC.SA (TX), Optional
10
105
150
910
40
42
40
3.4
1
2
3
4
5
6
30.5
20
14
7
8

10
The 1st batch of Freestyle V1 VTX, supports 2S-4S, A BEC supporting 2S-6S is included.
The 2nd batch and later, supports 2S-6S, and the BEC is not included.
Important Notes:
●Do not directly power this VTX with a 5S/6S battery for the 1st batch.
oUse 2S-4S VBAT, or included BEC, or FC with built-in BEC
oThe Freestyle VTX consumes up to 15W. If it is connected with FC that has a built-in BEC output,
make sure the BEC can provide enough current. For example, if the BEC provides 10V, it needs a
minimum of 1.5A current output.
●Removing the heat sink is not recommended because it is part of the design.
●Rotate the antenna as shown above before detaching it to reduce the risk of peeling off the UFL
connector.

11
HDZero Freestyle V2 Video Transmitter
The HDZero Freestyle V2 VTX is our 2nd generation 5.8GHz digital video transmitter which can be fitted
into most 3-5-inch HD drones. All sockets are well protected by the CNC case that provides durability, RF
shielding and improved signal integrity. A wire harness is included for solderless connection for power
and MSP UART port. The antenna and MIPI cable are secured by the included retention bar and screws.
1
Secured MIPI Connector
2
M2 Mounting Hole
3
Secured U.FL Connector
4
Keypad Connector
5
FW Update Connector
6
Power(7-25V)/UART Connector
7
Power/UART Harness
Power/UART
Connector
Cable
Color
Connected with
Ground
Black
Ground
Power
Red
Power
RX
Yellow
FC.TX
TX
White
FC.RX
SA
Blue
FC.SA (TX), Optional
1
2
5
6
7
6
3
4

12
HDZero VTX Installation Guide
Notes:
-VTX can be powered by VBAT or BEC. Check each VTX’s power requirement above;
-Use of capacitor is mandatory for HDZERO VTX;
-One UART is needed for OSD, Camera, VTX menu, MSP VTX;
-Never apply power on VTX without antenna installed and secured;
-Use RHCP antennas to match with SharkByte VRX RHCP patch antennas;
-Some VTXes do not have an SA pin, and they don’t support SmartAudio.

13
HDZero Firmware Update Guide
The firmware can be downloaded from www.hd-zero.com/document
Each revision contains firmware for all the VTX and VRX. The revision number is formatted as
revddmmyyyy.zip where “ddmmyyyy” denotes its release date.
Products
Firmware
HDZero Goggle
HDZEROGOGGLE_Revddmmyyyy.zip
HDZero VRX
HDZeroVRX_4SMA_Revddmmyyyy.zip
Sharkbyte VRX
SharkByteVRX_2SMA_Revddmmyyyy.zip
ScoutHD
ScoutHD_Revddmmyyyy.zip
Frsky SkyVisionHD
FrskySkyVisionHD_Revddmmyyyy.zip
Emax Transporter
EmaxTransporter_Revddmmyyyy.zip
HDZero Freestyle V1 VTX
FreestyleV1VTX.Revddmmyyyy.zip
HDZero Freestyle V2 VTX
FreestyleV2VTX.Revddmmyyyy.zip
HDZero Whoop VTX
WhoopVTX.Revddmmyyyy.zip
HDZero Whoop Lite VTX
WhoopLiteVTX.Revddmmyyyy.zip
HDZero Race V1 VTX
RaceV1VTX.Revddmmyyyy.zip
HDZero Race V2 VTX
RaceV2VTX.Revddmmyyyy.zip
HDZero Race V3 VTX
RaceV3VTX.Revddmmyyyy.zip
Foxeer VTX
FoxeerVTX.Revddmmyyyy.zip

14
VTX update Guide
All the zip files for each VTX contains HDZERO_TX.bin.
Steps to update VTX firmware:
(1) Format SD card (Choose FAT32 and Allocation Unit size to
4096 bytes);
(2) Power off VRX if it is on;
(3) Unzip content of corresponding VTX zip file onto SD-card, and
insert SD to the VRX module;
(4) Connect cable with module and VTX as shown right;
(5) Power on VRX module;
(6) If “Wait to Connect VTX…” or “Check cable …”, make sure (4) is
secured;
(7) If “Firmware update failed”, Repeat steps from (1);
(8) If “Firmware update successful”, VTX is updated;
(9) The HDZERO_TX.bin file is removed from the SD card automatically.
Note: Putting an empty file named as “DONOTREMOVE.txt” file on SD card root directory will prevent
HDZERO_TX.bin from being removed. It is useful when updating multiple VTXes.
VRX update Guide
Steps to update HDZero VRX
(1) Disconnect the cable connecting VRX and VTX, if it is connected;
(2) Unzip content of HDZeroVRX_4SMA_Revddmmyyyy.zip onto SD-card, insert SD into the module
(3) Power on VRX, and waiting for “Success”.
Steps to update Shark Byte VRX
(1) Disconnect the cable connecting VRX and VTX, if it is connected;
(2) Unzip content of SharkByteVRX_2SMA_Revddmmyyyy.zip onto SD-card, insert SD into the
module
(3) Power on VRX, and waiting for “Success”.
The firmware will be automatically deleted from the SD card after updating.
Note: Do not power off VRX while updating firmware until “Update Completed”. Otherwise VRX will not
be able to boot up next time.
Steps to flush VRX in case of not booting up
(1) Power off VRX;
(2) Unzip content of the file below onto SD-card, insert SD to the module;
a. - HDZeroVRX_4SMA_Revddmmyyyy.zip for HDZero VRX, or
b. - SharkByteVRX_2SMA_Revddmmyyyy.zip for Shark Byte VRX

15
(3) Move the switch to Bottom position with tweezers (not included);
(4) Power on goggle module, the red LED will be lit;
(5) Wait for red LED to turn off, on, and then off again (it may take over 10 min to complete);
(6) Power off, and move the switch to TOP position with tweezers;
(7) Repower goggle module, it should now boot up normally.

16
Setup and Getting Started with HDZero
OSD Setup
1. Prerequisitions
oBetaflight >= 4.4.0
oInav >= 4.1
oFlightOne >= 10.1.1.5576 | 10.1 Alpha 29
2. Update firmware VTX and VRX
-Download the latest firmware: www.hd-zero.com/document
-Firmware package (Rev_ddmmyyyy.zip) contains the firmware for all the VTX and VRX
3. Solder/Connect VTX UART to an available UART on your FC board
see installation diagram above
4. Flight controller Configuration (Use Betaflight as example)
-Connect the FC board to computer with an USB cable
-Start Betaflight configurator
-Go to Port TAB
-Activate VTX (MSP + Displayport) on UART number that is used to connect the VTX
-Save and Reboot
Note: A soft serial UART is not supported for VTX (MSP + Displayport).
As an example: UART5 on picture below is used for VTX (MSP + Displayport).
5. Restart/Connect Flight controller Configuration (Use Betaflight as example)
-Go to configuration tab

17
-Activate OSD function
-SAVE
-Go to OSD tab, and configure the items you want to show on your screen
-SAVE

18
Stick Movement
VTX Menu
Enter VTX Menu
Move Up
Move Down
Move Left
Move Right | Enter
Betaflight Menu
Enter Betaflight Menu
Move Up
Move Down
Move Left
Move Right | Enter
HDZero Camera Menu
Enter HDZero
Camera Menu
Move Up
Move Down
Move Left
Built-in Camera Menu
Enter Buit-in
Camera Menu
Move Up
Move Down
Move Left
Move Right | Enter
Move Right
Enter
Exit Camera Menu
Shotcuts
(OPT_A)
Shotcuts
(OPT_B)
Switch to 0mW
Exit 0mW
Switch to 0mW
Exit 0mW
Move
Move and Hold for 3 seconds