Saturday, June 17, 2023

AM (MW) Band And Electric Vehicles: Should We Worry?

Concern has been raised in the US over the exclusion of the AM radio band in new electric vehicle's (EV) entertainment systems. The radio industry say drivers could be deprived of a crucial source of news in emergencies. Some have even stated it's a deliberate attempt to silence conservative radio. Carmakers say that EVs generate more electromagnetic interference than internal combustion engine (ICE) cars, disrupting AM signal reception.

Around 20 % of the US radio-listening public listen to AM radio weekly, so one can't but wonder how well the platform would perform in emergencies - especially since most young people have little or no knowledge about AM - let alone have access  to an AM radio.

Be that as it may. I am curious to find out if the carmakers are right. Do electric motors and inverters  emit electromagnetic interference to the extent that AM reception is impossible? And will charging an EV at your home wreck havoc on your domestic AM radio?

I've had my EV parked outside the KONG HQ (and charging) the last few years during our DX-peditions, and no RFI has been noted. But our beverage antennas are far away from the car, and we have top quality coax feedlines. My FM antennas though are only 4-5 metres away and are not affected.

So, what needs to be done is to take the car, a receiver and an antenna to a location totally devoid of any RFI within many kilometres and see what happens - at standstill and at driving. This summer I will do that. There may be updates coming along before the full report. If you have any ideas concerning this test, please use the comments section below.


KONG HQ: Adding range to the 77-kWh battery (VW ID.5 GTX)

3 comments:

RADIO-TIMETRAVELLER said...

Hi Bjarne,

I would add, be sure while driving to test under acceleration as well as cruising.

Bill WE7W near Rochester, NY

Walt said...

Bjarne, I would imagine that it's very much dependent on the vehicle, as one hears how noisy some are, and quiet others are.

Bjarne Mjelde said...

Bill: Yes, and during deceleration when energy is sent back to the battery.

Walt: True. This test surely qualifies as "anecdotal evidence". Car makers have the additional challenge to fit an AM circut and antenna into the entertainment system. And the same test should be performed with an ICE car for comparison. Still, I'm curious, and there's only one way to find out...