Nothing kills an FPV session faster than video breakup or a failsafe. Signal interference is the invisible enemy every pilot faces.
Three Types of Video Interference
1. Multipath: Signal bounces off buildings and trees. The receiver gets direct + reflected copies at different times, causing ghosting and lines. Fix: circular polarized antennas (RHCP/LHCP) reject reflected signals.
2. Co-Channel: Multiple pilots on overlapping frequencies. Use an RF spectrum analyzer to scan the band and assign clean channels before a group session. Raceband spacing is 37MHz.
3. EMI: Your own drone generates electrical noise. Fix: add a 1000uF 35V low-ESR capacitor across ESC power pads, install an LC filter on VTX power, keep VTX antenna 5cm+ from motor wires.
Control Link
ExpressLRS at 2.4GHz with LoRa delivers rock-solid links at 250Hz with sub-4ms latency. Mount RX dipole in 90-degree V away from carbon. Use dynamic power: 25mW default, boost to 250mW+ only when needed.
Pre-Flight Check
Use a WiFi analyzer app at new spots. Avoid cell towers and high-voltage lines. For GPS Rescue: wait for 8+ satellites with HDOP under 1.0 before takeoff.
Good antennas, clean power, and ELRS give you the best chance of a rock-solid link anywhere.
