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The USA is bringing the demise of AM on itself.
The medium frequency band where they transmit AM radio is the most prone to interference from any arcing or switching sources of electricity. AM has no built in protection from that interference and is heard as buzzing or crackling noise from power line insulators, electric train/tram overhead wires and switchmode power supplies which are used in nearly all electronic devices including motor controllers.
The Federal Communications Commission (USA) has exempted transportation from having to comply with electronic pollution regulations. The main culprits are the pantograph arcing in electric trains and trams and the motor control and motors in electric vehicles. In petrol powered vehicles a simple solution is applied which is resistive spark plug leads and a couple of capacitors, which makes reception in vehicles possible. This makes petrol vehicles self policing possible.
Whilst in 2009 the US government at the behest of the telcos made a mandatory change from analog to digital TV, they still use AM which hit the marked in T model Ford time. Electric vehicles are all digital except for the AM/FM radio?
Digital Radio Mondiale has the greatest resistance to interference and can accommodate all AM and FM broadcasts in the USA in the vacated TV channels 2 - 6. In Australia the same opportunity exists for regional areas using the vacant TV channels 0, 1 & 2. For remote areas and Radio Australia we can follow the Radio New Zealand Pacific service which covers a huge area using high frequency (Short Wave) Digital Radio Mondiale in crystal clear sound.
Radio manufacturers appear to be abandoning AM radio receptions. My own survey of retailers, there bedside radios are sold with only FM or DAB and FM. No interference from devices/machines emitting RF from sparks. That's unless you live or work in a high rise building which consists of metal in its structure.
When it comes to cars with an electric drive train, the AM band is being ditched on the premise that its motor's electric field interferes with AM reception.
From my experience of driving a hybrid car, when the electric motors in the car are in operation, I have not noticed any interference while listening to AM especially at 1701kHz whose signal emanates from Mt Druitt, in Sydney's West. Its power is 500W.
I cannot explain why AM is being ditched from electric cars and on tabletop radios. Even hifi amplifiers such as the Sony STRDH790 7.2Ch don't have an AM section https://www.sony.com.au/electronics/av-receivers/str-dh790.
Thank you
Anthony, I don't believe the reasons for ditching things, Belfield, in the land of the Wangal and Darug Peoples of the Eora Nation