Drawback - With 2.4 Ghz, there are just 3 independant channels. So with many drones & its remote control devices in a room, plus extra Smartphones and notebooks connected to another WiFi hotspot, there will be much WiFi interferences which disable effective communications between the remote control devices and the drones. Experts told me that if you start more than 10 drones in a room or area, the WiFi communications is dramatically disturbed

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