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EU 5.8 GHz Channels Sticker
Which analog channels sit inside the EU band, at a glance.

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Two video transmitters together create interference on two more frequencies: one gap below the lower channel and one gap above the higher one. So never pick three channels with equal gaps: pilots on F1 (5740) and F4 (5800) put noise exactly on F7 (5860, because 2 × 5800 − 5740 = 5860), and whoever flies F7 gets broken-up video whenever the other two are in the air. These sets score best on ET’s IMD rating while staying inside the EU 5.8 GHz band: F1 F3 F7 for three pilots, F1 B3 B6 F7 for four.
Four pilots is a tight fit in the EU band (two channels only 31 MHz apart); three is the clean maximum. For analog VTXs at 25 mW.
Stick it on your goggles case or the field box.
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