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Important Instructions on Promotion to
HM30 Communication Range and Video Fluency
2021-10-16
In order to have the best communication range and video fluency with HM30 system,
please carefully read the below tips for choosing/mounting antenna and module
configuration.
1. Precautions on using HM30
1) There are four ways to acquire the video stream from HM30 ground unit: USB,
Internal WiFi, USB WiFI, and Ethernet.
2) When the environmental temperature is high or there is direct sunshine, it is
suggested not to use the Internal WiFi for video sharing to reduce internal heat.
3) It is also suggested not to run SIYI FPV and QGroundControl at the same time, not
even running one at backstage, as it still occupies bandwidth thereby lower the
communication range.
4) Only power battery and the SIYI original BEC are allowed to power the XT30
connectors on HM30 ground unit and the air unit directly. HD image transmission
requires high standard to the current level, the instancy of the current response, and
the current ripple, so power supply from the third-party BEC or from FC may interfere
the link stability and the image transmission range.
5) When you use a mobile device to connect with HM30 ground unit’s internal WiFi for
video display, mind that the distance between your mobile device and the ground unit
should be within one meter. If you expect for longer distance to connect the mobile
device, please use the USB WiFi modules selling by SIYI with optional transmitting
power.
6) It will cause video freeze or extra latency when the battery level of your mobile device
is low or its temperature is high, because the decoding speed is lower in such
circumstances.
2. Groud Unit Antenna Choice and Wireless Mode
1) 0 to 10 Kilometers FPV Flight
Two standard omni-directional antennas on HM30 ground unit.
Wireless mode: 5 to 8 km low latency.
Omni antenna signal is the worst on top direction, please fly within 100-meter
distance from home point.
2) 10 to 20 Kilometers GCS Flight
Two standard directional antennas on HM30 ground unit.
Wireless mode: 24 km long range.
Route flight through GCS is suggested as the antenna is directional.
Antenna is directional. Your drone must fly in front of your antenna and should not fly
in the opposite direction or fly top.