Comments by "Mikko Rantalainen" (@MikkoRantalainen) on "WHY Could 5G be DANGEROUS to Aircraft?!" video.

TL;DR: It's not known if the airplane manufacturers have too poor selectivity for their radio altimeters. There's 250 MHz buffer between 5G and airplane radio altimeter frequencies but the assumption is that the airplane manufacturers used such a poor implementation that such margin may not be enough. (I would guess there was no other reason but cost saving to not have more accurate radio receiver in the airplane.)
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@ddpeak1 Exactly. 250 MHz safety buffer is like 40 TV channels worth of bandwidth. TV sets were accurate enough over 50 years ago to separate 6 MHz channels. 250 MHz should be plenty safety margin for a radio receiver.
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