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"I suspect the removal of AM radio in EVs is also because the cost to RF shield the car against EM emissions in that frequency range was deemed too high for the audience it would address,.…"

The difficulty in suppressing switching noise/RFI is one of the stated reasons EV manufacturers give for removing AM reception. They say that keeping AM will increase EV costs.

If regulators/spectrum management were to agree to their request then that would imply a relaxation of existing EMI emission standards. With thousands of EVs on the roads the noise floor on the HF band and lower frequencies would become intolerable, the band would become unusable.

A while ago on HN I referred to a now-dated NATO communications tech note on interference that said the noise floor on the HF band had increased about 6dB. I went on to mention that about a decade ago I'd mentioned the NATO stats to an engineer from a HF transmitter manufacturing company at a trade show. He responded by asking me where I'd been in recent years and went on to state the noise floor on HF had since increased to about 17dB above the pre-digital switching era.

As I said that was about a decade ago when EVs were still only lab prototypes. If EV manufacturers are allowed to get away with emitting more EMI then the HF bands will become altogether unusable. And no doubt this is a serious problem.

EV manufacturers like Musk have enormous power and what worries me is that spectrum management authorities around the world will cave in further to pressure and relax EMI standards even more.

That increase in the noise floor from 6dB to 17dB was the result of spectrum management caving in to commercial pressure from the 1980s onwards. This was the era of deregulation and EMI regulations were loosened—EMR/noise testing etc. was not only relaxed but further outsourced.

It seems to me those who've a vested interest in the LF/MF/HF bands and want them preserved/saved from interference need to join forces and make concerted efforts to save them. An unlikely alliance of say the military, amateur radio (IARU), broadcasters and others speaking in unison to governments/ITU is what's needed to save these bands.

BTW, I once held an AR license which I got whilst I was still at school.



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