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Another wireless device that operates on bands close to 2.4GHz and the device is placed close
to the drone’s 2.4GHz wireless module can interfere the drone’s wireless link. For example,
some drones have both LTE link and point-2-point wireless link. Particularly, the LTE
operating on 2.3GHz band can be a problem. If the antenna of the LTE module is placed close
to the antenna of the 2.4GHz point-2-point wireless module, the receiver of 2.4GHz module can
be saturated by the LTE signal when it is transmitting. Thus, the range/performance of the
2.4GHz module will be significantly degraded.
Interference by HDMI
When HDMI source/cable is close the antenna of 2.4GHz wireless modem, the HDMI
source/video will interfere the 2.4GHz wireless signal (including WiFi).
https://h30434.www3.hp.com/t5/Notebooks-Archive-Read-Only/HDMI-interfering-with-WiFi-
http://www.dslreports.com/forum/r27141612-HDMI-connect-interferes-with-wifi
It is recommended that install the antenna at least 25cm away from the HDMI source/cable. A
good shield HDMI cable can be a resolution too. The following shield HDMI cable uses 360-
degree shield termination, which is recommended practice.
https://interferencetechnology.com/hdmi-cables-emi/
http://www.l-com.com/content/Article.aspx?Type=P&ID=10699
http://www.l-com.com/audio-video-micro-hdmi-to-hdmi-cables
http://www.l-com.com/audio-video-hdmi-female-to-micro-hdmi-male-adapter
RF cable connector/Antenna connector check
Before flight, check if the antennas are connected to the modules. Running module without
antenna connected results in very short range and potentially can damage the module. It is
recommended to check the connection of all RF connectors. Loose connection can degrade the
range significantly.
Antenna placement
