DIVIMATH HDZero User manual

1
HDZero Video Transmitters
Whoop Whoop Lite Race V1 Race V2 Freestyle
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.

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Contents
What is HDZero? 1
HDZero VTXes 3
HDZero Whoop Video Transmitter 4
HDZero Whoop Lite Video Transmitter 5
HDZero Race V1 Video Transmitter 6
HDZero Race V2 Video Transmitter 7
HDZero Freestyle Video Transmitter 8
HDZero VTX Installation Guide 10
HDZero Firmware Update Guide 11
VTX update Guide 12
VRX update Guide 12
Steps to update HDZero VRX 12
Steps to update Shark Byte VRX 12
Steps to flush VRX in case of not booting up 12
Setup and Getting Started 14
OSD Setup 14
1. Prerequisition 14
2. Update firmware VTX and VRX 14
3. Solder/Connect VTX UART to an available UART on your FC board 14
4. Flight controller Configuration (Use Betaflight as example) 14
5. Restart/Connect Flight controller Configuration (Use Betaflight as example) 15
Stick Movement 16
Using VTX Menu (Applicable to all HDZero VTXes) 17
Using SmartAudio (Not applicable to HDZero Whoop VTX) 18
Help and Troubleshooting 20
FAQ 20
Trouble Shooting 20

3
HDZero VTXes
Whoop
Whoop Lite
Race V1
Race V2
Freestyle
Dimension
32x32
32x32
27x45
34x34
40x40
Mounting Pattern
25.5x25.5
M2
25.5x25.5
M2 (Soft)
20x20
M4 (Soft)
20x20
M4 (Soft)
30x30
M3 (Soft)
Weight
5.3grams
4.5grams
7 grams
6 grams
28grams
Power Input
2S-6S
1S-3S
2S-6S
2S-6S
2S-6S
Power Consumption
5~6W
5-6W
5~6W
5~6W
6~15W
RF Power Output
25mW,200mW
25mW,200mW
25mW,200mW
25mW,200mW
25mW,200mW (500mW, 1W
if with HAM license)
Secured U.FL
No
Yes
Yes
Yes
Yes
Antenna Included
Not included
Not included
Not included
Not included
Polarized (RHCP)
Smart Audio
No
Yes
Yes
Yes
Yes
MSP Display Port
Yes
Yes
Yes
Yes
Yes
Application
Whoop
Tiny Whoop
Race
Race
Freestyle

4
HDZero Whoop Video Transmitter
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 –26V (2S –6S). Though the Whoop VTX has an integrated surge protection circuit, a
large capacitor (450+uF) parallel with battery leads is mandatory to smooth the power supply of the whole quad.
It is highly recommended to use a BEC (8-12V) to power this VTX. The maximum 1A current will be drawn from
BEC.
This VTX is designed for low-speed whoop application. It is vulnerable to be damaged by crash due to: (1) the UFL
connector is easily peeled off due to no antenna retention, and (2) it doesn’t support soft mounting. Though the
VTX can be mounted on a racing and other high-speed quad, it is highly recommended to consider HDZero Race
(V1 or V2) for such cases.
This VTX does not support
Smart Audio.

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 (1S-3S).
-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 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 tiny whoop quad which cares about every added gram.
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 quad, it is highly recommended to consider HDZero Race (V1 or V2) for
such cases.
Solder pads:
1
MIPI Connector
2
Status LEDs
3
Power/UART/SA solder pads
4
u.FL Connector
5
Protection Case
6
Protection case clipper
G
Ground
V
2.8V -13V
RX
FC.TX
TX
FC.RX
SA
FC.SA (TX), Optional
2
3
4
6
5
1

6
HDZero Race V1 Video Transmitter
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 –26V (2S –6S). Though the Race VTX has an integrated surge protection circuit, a
large capacitor (450+uF) parallel with battery leads is mandatory to smooth the power supply of the whole quad.
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
7-26V (2S-6S)
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.

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HDZero Race V2 Video Transmitter
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 –26V (2S –6S). Though the Race VTX has an integrated surge protection circuit, a
large capacitor (450+uF) parallel with battery leads is mandatory to smooth the power supply of the whole quad.
1
Power In (G=Ground, V=7-26V)
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:
-SA Pin is needed to connect with FC only when you decide to let FC fully controls VTX’s freq and
outputting power. Read Using SmartAudio section to setup VTX table, and etc. Note that VTX Menu
is not available for this case.
-If SA pin is not connected, VTX will use its own logic to control freq and outputting power. It has VTX
Menu to setup these parameters.
1
2
3
4 5
67
8
910
11
12
14
13
4x 4x 1x
8x 8x
4x
1x
15

8
HDZero Freestyle Video Transmitter
The HDZero Freestyle 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 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 Mouting 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

9
The 1st batch of Freestyle 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.
HDZero Freestyle VTX is compliant with FCC 47 CFR 97.215(c). It is limited to 25mW/200mW out of the
box, but it is capable of up to 1W if you have the required HAM radio license to use this power output.
Download the special firmware from www.hd-zero.com/document to enable higher RF output modes.
Here are the steps:
1. Download firmware Unlock_FreestyleVTX.zip.
2. Unzip it to the root directory of SD Card.
3. Use the VRX to flash this firmware to the VTX.
4. Power on the VTX, BLUE LED will flash 3 times after it is done. This step unlocks VTX.
5. Power the VTX off.
6. Unzip normal VTX firmware to the root directory of SD Card.
7. Use the VRX to flash this firmware to the VTX.
8. The higher RF output options will now be available.
Please note once the VTX is unlocked, there is no need to unlock it again when there is newer firmware
available.

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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;
-Never apply power on VTX without antenna installed and secured;
-Use RHCP antennas to match with SharkByte VRX RHCP patch antennas;
-Whoop VTX does not have SA pin, and it does not support SmartAudio.

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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. And revision number is formatted as
revddmmyyyy.zip where “ddmmyyyy” denotes its release date.
Products
Firmware
HDZero VRX
HDZeroVRX_4SMA_Revddmmyyyy.zip
HDZero Freestyle VTX
FreestyleVTX.Revddmmyyyy.zip
HDZero Whoop VTX
Whoop_TX5S.1 Revddmmyyyy.zip
HDZero Whoop Lite VTX
WhoopLite_Race.Revddmmyyyy.zip
HDZero Race V1 VTX
WhoopLite_Race.Revddmmyyyy.zip
HDZero Race V2 VTX
WhoopLite_Race.Revddmmyyyy.zip
Shark Byte TX5S.1
Whoop_TX5S.1 Revddmmyyyy.zip
Shark Byte TX5M.1
TX5M.1.Revddmmyyyy.zip
Shark Byte TX5R.1
WhoopLite_Race.Revddmmyyyy.zip
Shark Byte RX.1
SharkByteVRX_2SMA_Revddmmyyyy.zip
Shark Byte ScoutHD
ScoutHD.Revddmmyyyy.zip

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VTX update Guide
All the zip file 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) HDZERO_TX.bin is removed from 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 to 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 to the module
(3) Power on VRX, and waiting for “Success”.
The firmware will be automatically deleted from 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
(3) Move the switch to Bottom position with tweezers (not included);

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(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.

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Setup and Getting Started
OSD Setup
1. Prerequisition
oBetaflight >= 4.2.8
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 MSP protocol with 115200 baud-rate on UART number that is used to connect the
VTX
-If you have connected the SA pad to your FC, to use SmartAudio functionalities, activate the
Smartaudio protocol on the UART number you used to connect the SA pad.
-Save and Reboot
Note
-A soft serial UART is not supported for MSP protocol.
-Not all UART ports of FC support SmartAudio, check the FC user manual first.
As an example: UART5 on picture below is used for MSP, and UART3 is used for Smartaudio

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5. Restart/Connect Flight controller Configuration (Use Betaflight as example)
-Go to configuration tab
-Activate OSD function
-Activate Telemetry function
-SAVE
-Go to OSD tab, and configure the items you want to show on your screen
-SAVE
-Go to CLI tab to enable MSP Display Port
set osd_displayport_device = MSP
set displayport_msp_serial = YOUR_UART_PORT_NUMBER - 1
save
In our example, we used UART5 for MSP Connection (UART5 - 1 = 4) , we will enter this :
set osd_displayport_device = MSP
set displayport_msp_serial = 4
save

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Stick Movement
Enter VTX menu Move Up Move Down
Enter HDZero
Camera menu
Move Up Move Down
Move Up Move Down
Enter Camera
(Built-in) menu Move Left Move Right Enter Exit Camera menu
Move Left Move Right | Enter
Move Left Move Right | Enter
Switch to 0mW Exit 0mW
For HDZero Cameras
For Non-HDZero
Cameras
VTX Menu
Shortcuts
Move and Hold for 3 seconds
Move
Enter BetaFlight menu Move Up Move Down Move Left Move Right | Enter
BetaFlight Menu

17
Using VTX Menu (Applicable to all HDZero VTXes)
VTX menu will be available when
- The VTX does not support SmartAudio, or
- VTX.SA pin is not physically connected with FC, or
- VTX.SA pin is connected but the related UART port of FC is disabled.
All HDZero VTXs have the following settings for its RF power level management. These settings can be
changed using the VTX menu.
POWER: The desired RF power level is selectable
between 25mW, 200mW (and 500mW or MAX for
certain VTXes). The actual RF power level depends
on the following settings and FC status.
PIT_MODE: The three modes of this setting are:
-P1MW: The output RF power will be 0.1mW (in
order to not interfere with other pilots) in this
mode. If the quad is armed, RF output power
will be automatically set to the POWER within
seconds.
-0MW: There will be zero RF output in this mode. If quad is armed, RF output power will be
automatically set to POWER within seconds.
-OFF: The output RF power will be set to POWER setting.
(Note that after first arm, the vtx will not enter pitmode again until vbat power is reset)
LP_MODE:
-ON: If PIT_MODE is OFF and the quad is disarmed, the RF power level will be forced to 25mW
regardless of POWER setting. The output RF power will be set to POWER setting when quad is
armed.
-OFF: The output RF power will be set to POWER setting.
OFFSET_25MW: It is to fine tune the RF output power to be exactly 25mW. The range is [-10:10], and
step size is about 0.3dB per step.
Notes:
-HDZero VTX will still become hot even on P1mW mode. It is better to keep VTX on PIT 0mW mode
when it will be idle for a while. Though the receiver will not have live video on this mode, it will
come back as soon as the quad is armed.
-Use sticks shortcut to enter 0mW, and to exit 0mW mode.

18
Using SmartAudio (Not applicable to HDZero Whoop VTX)
HDZero Race VTX can be controlled by FC using the TBS SmartAudio V2.1. In this case, the VTX will
output RF power and channel commanded by FC directly. To avoid conflict, the VTX menu is not
available if SmartAudio is enabled.
Notes:
-HDZero Race VTX outputs 0.1mW when SmartAudio PIT mode is ON.
-HDZero Race VTX does not support SmartAudio out range PIT mode.
-When HDZero Race VTX boots up, it will automatically detect the existence of a valid SmartAudio
link with FC within 10 seconds. If the link exists, FC will fully control race VTX’s RF output power and
working frequency.
VTX table needs to be set as below. Please note that HDZero Race VTX supports all 8 channels (R1 ~ R8)
on R band, and 2 channels (F2 and F4) on F band.
The above setting can also be done with the following CLI commands:
vtxtable bands 6
vtxtable channels 8
vtxtable band 1 BOSCAM_A A FACTORY 0 0 0 0 0 0 0 0
vtxtable band 2 BOSCAM_B B FACTORY 0 0 0 0 0 0 0 0
vtxtable band 3 BOSCAM_E E FACTORY 0 0 0 0 0 0 0 0
vtxtable band 4 FATSHARK F FACTORY 0 5760 0 5800 0 0 0 0
vtxtable band 5 RACEBAND R FACTORY 5658 5695 5732 5769 5806 5843 5880 5917
vtxtable band 6 IMD6 I FACTORY 0 0 0 0 0 0 0 0
vtxtable powerlevels 3
vtxtable powervalues 14 23 0
vtxtable powerlabels 25 200 0
save

19
With SmartAudio, the user can change channel number and power level even when quad is in the air.
Example 1: Map a 3-phase button (aux channel 3) to 3 different RF power levels (25mW, 200mW, and
0mW).
VTX <index> <aux_channel> <vtx_band> <vtx_channel> <vtx_power> <start_range> <end_range>
vtx 0 2 0 0 1 900 1300
vtx 1 2 0 0 2 1300 1700
vtx 2 2 0 0 3 1700 2100
（aux ch -1）
0 means no change
vtx 0 2 0 0 1 900 1300
vtx 1 2 0 0 2 1300 1700
vtx 2 2 0 0 3 1700 2100
save
Example 2:Map a 3-phase button (aux channel 4) to Channel R1, R2 and F2.
VTX <index> <aux_channel> <vtx_band> <vtx_channel> <vtx_power> <start_range> <end_range>
vtx 3 3 5 1 0 900 1300
vtx 4 3 5 2 0 1300 1700
vtx 5 3 4 2 0 1700 2100
0=no change
vtx 3 3 5 1 0 900 1300
vtx 4 3 5 2 0 1300 1700
vtx 5 3 4 2 0 1700 2100
save
3 different RF power levels are specified on the above table. #1 and #2 specify 25 mW and 200mW RF
power respectively, and #3 is to turn off RF output completely.
HDZero Race VTX will become very hot if it is on the bench without airflow, even if it is on 25mW or
PIT mode. It is recommended to put VTX on 0mW while quad is waiting on the line.
When #3 is selected from SmartAudio menu by mistake, the receiver will lose video feed since VTX is not
transmitting. Use stick command to exit 0mW mode.

20
Help and Troubleshooting
FAQ
1
Facebook Group and
Discord Server?
www.facebook.com/groups/HDZero
https://discord.gg/JPesSHpmCU
2
Does VRX have low
voltage alarm?
VRX does not have low voltage alarm. We recommend using an in-line battery
alarm (not included) between the battery and DC cable
3
How does VRX power
cable work?
DC cable has integrated DC regulator which converts from 3S-6S to fixed 7.8V
output. (Manual says 3S-4S)
It is very important to unplug DC cable from battery after flight. Otherwise,
DC cable will suck up battery power and cause permanent damage to battery.
Trouble Shooting
1
Video feed is working
but no OSD
(a) VTX/VRX Firmware mismatch: Update both VTX and VRX from the
same firmware release.
(b) Wire connection: TX and RX of FC board should be connected with
RX and TX pads of VTX respectively.
(c) Betaflight setting: Instruction on Page 10/11 on Shark Byte User
Manuel 08042021.pdf
- Betaflight 4.2.8 or above
- CLI commands
set osd_displayport_device = MSP
set displayport_msp_serial = n-1//n= serial port number minus 1
save
get displayport_msp_serial //to verify the value previously set
(d) Try another UART port of FC ( avoid to use soft-serial and SA ports)
2
No Blue LED on VTX
From Firmware Rev30092021, Blue LED works as the following way:
(1) Flashing at 1Hz periodically if *no* camera is found after VTX is
powered up
(2) Flashing 8 times if MSP connection is established with FC after VTX
is powered up
(3) Remains OFF for HDZero Micro Camera(Beta), ON for all other
cameras.
If a Non beta HDZero Micro camera is attached, and get NO blue LED,
please
(a) Check if MIPI cable is secured on both end of camera and VTX, and
check if cable itself is fine
(b) Carefully check VTX MIPI connector if there is any bent pin
(c) If it is Foxeer Digisight Camera, make sure it is NOT on analog mode
- Digisight goes to analog when pressing left for 3 sec
- Use stick commands blindly or disconnect mipi and use external
joystick.