FPV channel planner
Choose 5.8 GHz video channels for a group of pilots — analogue bands, HDZero, DJI and Walksnail — keeping them apart and away from intermodulation products, with a frequency table and a range estimate for video and ExpressLRS links.
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How to use it
When four or five of us fly together on a mix of analogue, HDZero and DJI, picking channels by habit ends with someone’s picture breaking up. This tool picks one channel per pilot so that the signals are as far apart as they can be and no third-order intermodulation product lands on anyone.
How to use it
Planner
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Add a row per pilot and choose their video system. Analogue pilots can use any band you tick (A, B, E, F, R, L); Analogue, Raceband only limits a pilot to R1–R8. If someone can’t change channel, set it and the plan works round them.
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Press Plan channels. The tool tries every combination when there are few enough, otherwise it hill-climbs from a few hundred random starts. It scores a plan on the gap between neighbouring signals' edges (centre spacing less half of each signal’s width — 20 MHz for DJI and Walksnail at 20 MHz, 27 MHz for HDZero, 40 or 60 MHz for the wide DJI modes, about 20 MHz for analogue, which you can change) and on how close the nearest third-order intermodulation product (2a − b, a + b − c) comes to a channel.
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The spectrum shows each pilot’s channel as a block and every intermodulation product as a red tick; the list underneath says which products fall near whose channel.
The only 5725–5875 MHz box keeps analogue pilots inside the band that is licence-free in much of the world. Which channels and how much power you may use where you fly is for you to check.
Frequencies
The analogue band tables and the channel lists of the digital systems, with sources:
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Analogue A, B, E, F, R and L: Oscar Liang’s 5.8 GHz FPV channels and frequency chart (the same figures as Betaflight’s VTX tables).
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DJI O3: DJI’s O3 Air Unit specifications — 40 MHz: one channel, 5794.5 MHz; 20 or 10 MHz: 5768.5, 5804.5 and 5839.5 MHz.
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DJI O4: dji.com O4 Air Unit specs — 60 or 40 MHz: 5794.5 MHz; 20 or 10 MHz: 5768.5, 5789.5 and 5814.5 MHz (60 MHz only with Goggles 3 or N3).
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DJI FPV / Vista and Walksnail Avatar at 20 MHz (FCC): 5660, 5695, 5735, 5770, 5805, 5878, 5914 and 5839 MHz, from Oscar Liang’s chart and his Avatar set-up guide; in CE mode Avatar offers only CH1–CH3 and CH8.
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HDZero: R1–R8, E1, F1, F2 and F4, plus L1–L8 once low band is unlocked (HDZero VTX user manual v0.7).
There are notes on 1.2/1.3 GHz and 2.4 GHz video too.
Range
A free-space link budget for a video link and an ExpressLRS control link: transmit power, antenna gains, losses and receiver sensitivity give the path loss you can afford, and from that the distance where the signal falls to sensitivity plus your fade margin. For ExpressLRS the sensitivity comes from the packet rate, using the limits in the ExpressLRS documentation’s Signal Health page (for example −108 dBm at 250 Hz on 2.4 GHz, −117 dBm at 100 Hz on 900 MHz). Video receivers rarely publish a sensitivity; −90 dBm is my assumption and you can change it. The tool also gives the first Fresnel zone radius and the height needed above flat ground for 60 % clearance, including the earth’s bulge.
Free space is the best case: low over the ground, through trees or behind your own body you will get much less. For antennas see the antenna calculator, and for terrain and ground reflections the propagation tool.
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