Interference Wars

The electric vehicle finds itself in the middle of the big debate over the future of AM radio. Could the AM dial get pushed off to the side?

By Ernie Smith

Today in Tedium: As you may or may not know, I have no deep love for Sen. Ted Cruz (R-TX), the Republican senator who once forced a government shutdown days before I was about to go on a honeymoon to a national park, earning him “enemy for life” status in my book. (Apologies if you’ve heard this one before; I bring this anecdote up often.) Politically, we don’t see eye to eye on much. But it has been interesting of late to see this guy going so full-throated on … checks notes … AM radio! Cruz cosponsored a bipartisan bill earlier this year to require vehicles, particularly electric vehicles, to continue to offer AM radios at no additional charge to customers. And that bill would have passed the Senate this week, but Sen. Rand Paul (R-KY), a man who hates mandates even when they support the talk radio icons that brought him to prominence, scuttled a unanimous consent vote and attempted to attach it to an endeavor that would end a popular tax credit for EVs. (Libertarians!) So, why is AM radio suddenly at risk? Today’s Tedium explains. — Ernie @ Tedium


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Car Radio

(Mpho Mojapelo/Unsplash)

Why is AM radio suddenly at risk?

The average car has numerous variables that must be considered during the construction and manufacturing process. What works well in one sense might mess up something else—and AM radio, surprisingly enough, is one of those things that can cause problems of electrical interference in vehicles.

Now, to be clear, radio interference is a problem with lots of vehicles, internal combustion engines included. As Popular Mechanics noted in a 2006 story about a man competing against radio interference when trying to listen to a baseball game in his car:

There are three classes of RF noise—constant, intermittent and engine-speed following. Our hapless father’s problem was in the latter category—his noise varied up and down in pitch and volume as his engine sped up and slowed down. This type of noise is caused by something that varies its speed with the engine. Likely culprits include the ignition, the alternator or even a fuel injector. Constant-speed noises are usually caused by an electric motor--most likely the electric fuel pump found in the tank of most modern vehicles, which runs at a constant speed anytime the engine is running. An electric fan motor will also run at a constant speed--until you change the fan setting or turn it off. Intermittent noises are easier to associate with a source, such as an electric seat adjuster or a power-window motor. In other words, even though the noise comes from a radio speaker, it may be caused by any manner of device anywhere on your vehicle.

The problem is, electrical vehicles create new challenges for radio interference, in part because they use switching power supplies. In some designs, this power supply can directly compete with the very frequencies used by AM radios.

(As explained in Managing Electric Vehicle Power, a 2020 book published by the standards body SAE International, this can be very noticeable in general use:

One area where automotive designers are concerned about creating interference is in the AM radio band. Most automobiles have an AM radio that has a very sensitive, high-gain amplifier tunable from 500 kHz to 1.5 MHz. If a component emits a signal within this band, it will probably be audible on the AM radio. Many switching power supplies use switching frequencies within this AM band, which leads to issues in automotive applications. As a result, most automotive switch-mode supplies should use switching frequencies that are above this band, sometimes even 2 MHz or higher. If there is insufficient filtering at either the input or the output of a switching power supply, some of this switching noise may find its way into other subsystems that may be sensitive to the root or subharmonic frequencies.

If you make cars or other types of electric vehicles and learn that a feature like AM radio interferes with your design, it might trigger a bit of cost-benefit math. It’s pretty obvious math, at one level: AM radio is only used by a minority of users anyway, and redesigning your vehicle could create additional costs that would then be passed down to the consumer.

Of course, companies like BMW and Tesla were likely to give up the feature, rather than do a bunch of extra work for a seemingly unnecessary feature. BMW dropped it on its electric vehicles way back in 2014!

The problem is, though, that AM is necessary, as it’s used for numerous things, not the least of which is emergency broadcasting.

As this story started getting attention earlier this year, the National Association of Broadcasters launched a campaign based on one simple idea: When other types of broadcasting aren’t available, AM radio is often the medium of last resort.

“With its unique ability to reach a wide geographic area, AM radio offers many Americans struggling with poor, or non-existent, cellular and broadband coverage a chance to stay connected,” the association wrote on its campaign’s page. “Despite this, some auto manufacturers have begun discontinuing AM radio from the dashboard. Instead, they would shift the cost to car buyers, who would need to use cellular data to stream AM stations.”

NAB’s campaign has been successful with the people it needs to reach. Despite Rand Paul’s dramatic gesture, the AM Radio for Every Vehicle Act has more than 200 cosponsors between the House and Senate. But Paul’s move has created uncertainty, and that uncertainty favors manufacturers who want to drop AM radio like a bad habit—emergency broadcasts be damned.

“Although the auto industry’s investments in electric vehicles are critical to addressing the climate crisis and reducing greenhouse gas emissions, automakers need not sacrifice the benefits of radio in the process.”

— Sen. Ed Markey (D-MA), a sponsor of the AM Radio for Every Vehicle Act, in a press release from last fall asking major auto manufacturers why they were attempting to remove AM radio from their vehicles. In March, Markey released answers from automakers, eight of whom had told him that they had gotten rid of it in at least some models. Many responses were telling, most technical in nature. But in at least one case (Ford), the reason was, essentially, “it’s too old.” Which doesn’t feel like the answer Markey wanted to hear—as highlighted by the fact that Ford reversed the removal, which it was also planning to bring to its gas-powered vehicles, after pressure from legislators.

Tesla Console

Tesla was relatively early to the no-AM movement. (Jonas Leupe/Unsplash)

Eight excuses automakers gave a senator for wanting to remove AM radio

  1. “We believe electrification amplifies the attributes our customers love, such as performance, capability, and convenience. Further, we believe disruptive technology allows us to enrich the customer experience. In all aspects of the vehicle, we continually look for cost-effective, innovative solutions to unlock new capabilities.” — Christopher A Smith, the Chief Government Affairs Officer, Ford.
  2. “The resulting electromagnetic interference impacts the strength of the AM broadcast signal, causing severe disruption to AM radio transmission that makes the signal reception unstable and unusable. Despite these challenges, Tesla understands how important it is for Tesla owners to have access to preferred media, including AM radio, during daily commutes.” — Rohan Patel, Senior Director, Public Policy & Business Development, Tesla
  3. “Publicly available research has well established that the electromagnetism of EVs intersects the same spectrum as AM radio waves, interfering with the AM signal and diminishing audio quality. As your letter indicates, digital radio offers a simple alternative to deliver high quality AM content to EV drivers.” — James Chen, Vice President, Public Policy, Rivian Automotive
  4. “At this point, there are no plans to introduce AM radio in the future. There are no plans to delete FM radio in future Polestar cars.” — Gregor Hembrough, Head of Polestar Automotive USA
  5. “Our decision to not support AM radio was primarily linked to our electrification strategy. If Volvo Cars had continued to provide AM radio, our BEVs and PHEVs likely would have experienced EMC disturbances and this could result in poor performance.” — Anders Gustafsson, Senior VP Americas and President and CEO, Volvo Cars
  6. “The challenge of AM radio interference and static already exists in ICE vehicles, but the problem is significantly exacerbated in EVs. Our engineers have investigated hardware and software methods to reduce the interference, but the performance did not meet our requirements. Additional countermeasures (e.g., via metallic cages/shielding, additional filter) of the motor, battery and other electromagnetic producing equipment could further reduce the interference, but has a substantial impact on EVs’ range and performance due to the added weight.” — Anna Schneider, SVP Industry & Government Relations, Volkswagen
  7. “BMW made the decision to not include analog AM radio broadcasting in its EV and PHEV models beginning with the BMW I3 in 2014 primarily for two reasons: 1) electromagnetic interference creates poor analog AM radio reception quality and 2) technological innovation has afforded consumers many additional options to receive the same or similar information.” — Adam McNeill, Vice President of Engineering, US, BMW
  8. “In North America, many AM broadcasters have made their content available via compatible smartphone apps, which can be used via Apple CarPlay and Android Auto in the MX-30.” — Daniel V. Ryan, Vice President of Governmental and Public Affairs, Mazda

I Phone Headphones

The iPhone’s headphone jack, another example of a century-old technology that didn’t need to be killed. (freestocks/Unsplash)

Why are modern technology companies obsessed with killing established technologies that just work?

In many ways, one can see the direct parallels between AM radio and the demise of the headphone jack in smartphones. In both cases, it feels like a situation where a long-established technology was essentially getting uprooted because it started to get in innovation’s way.

With the iPhone, the headphone jack was a single-purpose port in a multifunctional world, one that got in the way of Apple’s desire to waterproof the phone and upgrade its cameras, and discouraged the uptake of wireless devices.

Greg Joswiak, the company’s current senior vice president of worldwide marketing, was blunt in his comments to BuzzFeed News.

“The audio connector is more than 100 years old,” Joswiak says. “It had its last big innovation about 50 years ago. You know what that was? They made it smaller. It hasn’t been touched since then. It’s a dinosaur. It’s time to move on.”

(This feels like Ford’s approach to the AM Radio problem. No legislators to stop them, however, in Apple’s case.)

There was also the factor of interference. As Apple told the outlet, the headphone jack became a problem because one component interfered with another, and when they tried to move it, the headphone jack got in the way. If it wasn’t there, the phone could do more.

Interference is, in many ways, the problem that AM radio is running into in its primary home, the vehicle. The big problem with AM radio, in the eyes of automakers, is simple: Because it wasn’t built with the automobile in mind, auto manufacturers have to work around it—which is holding back a new generation of innovation.

The cost-benefit analysis was done, and they figured out that to properly add AM radio, this uncommon use case would add thousands of dollars to the cost of this already costly vehicle. (On the other hand, a bunch of other manufacturers have pulled off AM radios in EVs without a lot of complaining, so—I’m sorry for saying this—your mileage may vary.)

The fact is, AM radio is often not the best technology for the job, but it works well, and can be used by many people for many reasons. While you wouldn’t want to listen to an album on it, it can carry voices and real-time information easily, and it has broad reach in areas where cell phone signals do not have a shot at getting through.

When I traveled through mountains on my follow-up trip to a national park to make up for the one Ted Cruz took away from me in 2013, my cell phone signal would go out. But you know what didn’t as we got high up those mountains? The radio.

But most people aren’t driving up mountains—all this extra work to support AM radio gets in the way, just like the headphone jack once did.


The maximum level of wattage that American AM radio stations are allowed to use under FCC regulations. These stations, during the day, have feeds that can reach about 100 miles away from the antenna’s location. However, at night, due to an effect called skywave propagation, the transmissions of these stations can reach many hundreds of miles further, making them particularly useful for reaching into areas other types of broadcast signals cannot, particularly rural areas. (Shortwave radio, which uses different radio frequencies, can travel even further thanks to the same effect.)

WHAS Radio Tower

A radio tower for WHAS-AM, Kentucky’s largest AM radio station. (Doc Searls/Flickr)

If AM radio receives this body blow, do broadcasters stop investing in it? Just look at what’s happening on cable

During the pandemic, you probably remember the meme around MTV airing hours of reality show reruns per day, instead of anything that people would actually want to watch.

But the thing you might have missed is that this is happening to most cable networks these days. TBS and USA, for example, have seen their originally programming slate essentially murdered in favor of streaming services. The reason is that entertainment companies have made a bet that because their target audiences have chosen to move to streaming, they are no longer putting their money into original programming for cable television, and that has caused advertisers to leave. (I don’t love linking to the NYT, but they have a great piece on this very topic.)

This transition has not been lost on cable providers—the recent carriage fees conflict between Charter and Disney was essentially built around this schism. It’s a debate about value, essentially—if the networks we carry just spit out Big Bang Theory reruns that they can get for $10 a month on streaming, what, honestly, are they getting from us?

AM radio already went through a transition like this in the 1980s, when most music broadcasts moved to FM. (It led to the rise of conservative talk radio—which, honestly, is what this whole conflict is about for Ted Cruz.) But knowing that most new vehicles wouldn’t have AM radio would be much more existential—it could essentially lead commercial programmers to change how they think about investing in this vital service. Is radio at risk of looking like a rerun wasteland, too?

After all, the technology of AM radio is much harder to manage than a podcast. With podcasts, all you have to do is put an MP3 file on an RSS feed. With radio, you have to manage an antenna—and if you run a radio station, you have to manage your own antenna.

Knowing that high-value consumers have chosen a vehicle that essentially shuns your medium changes what gets made and who uses it. Broadcasters, who have literal millions of dollars invested in antennas, have a lot to lose if AM radio gets left on the cutting room floor, another piece of debris pushed to the side because of innovation.

No wonder broadcasters are fighting back.

Rand Paul’s POV on the AM radio debate is interesting, and deserves a moment of analysis, because it is essentially a clever playing-both-sides kind of argument here.

Paul, as a libertarian, is a man who has never seen a subsidy that brought him joy. And in many ways, his attempt to remove the electric vehicle subsidy while blocking the requirement on AM radio essentially gets EV automakers what they want—a way to build cheaper EVs, which after many false starts, they’re finally ready to invest in at scale—at the cost of something they don’t. You want to make cheaper EVs without AM radio? Great, but the government won’t subsidize it.

As he told RFD-TV in November:

Some of the new electric cars, what they’re saying is, is that the battery is so strong that it disrupts the am signal. So there’s an extra cost if you want to have AM radio in electric cars. And what I’ve said is if this is a problem for AM radio, maybe we shouldn’t be subsidizing these cars. You get people $7,500 per car to buy them, and it’s really the only reason people are buying electric cars, and it’s still a small percentage. It’s about 1 to 2% of the public has an electric car, and so it probably wouldn’t grow if we got rid of the subsidies, and then we wouldn’t have the AM radio problem.

Paul seems to have made some interesting bets here: One, that his base hates electric vehicles (though he’s been seen in the past in one driven by his most ideologically aligned House counterpart) and will support efforts to damage their popularity, and two, that the auto industry is so excited about electric vehicles that they will willingly give up this subsidy that he hates (but that consumers love) to ensure that they can make cheap ones.

Long story short, Rand Paul is no fool. (If you want to see Ted Cruz and Rand Paul fight on the Senate floor, we got you covered.)

I think what’s going to happen here is that Paul’s stance will likely be a minority stance (as libertarian stances often are in the modern political environment), but it could pick up enough steam, particularly among auto-industry folks, that it wins the day. On the surface, it feels reflexive, but it’s deeply clever, and is a smart bit of gamesmanship that might actually pick up some steam if it’s debated. It gives automakers the win they want by motivating them to build cheaper vehicles.

If you ask me, though, I’d like to see AM radio live on another day. However, handheld AM radios are cheap and accessible, plus you can plug them into your car. (There’s a long legacy of consumers doing stuff like this.) But if it represents the difference between us getting sub-$20,000 electric vehicles and those vehicles staying out of reach for normal consumers, that conversation becomes more interesting.

Would the removal of AM radio from the next generation of vehicles be enough to murder a bedrock part of broadcasting? That’s the other variable at play, and the one element that Paul’s gamesmanship fails to consider.

If that’s the price—the loss or permanent damaging of a bedrock communications system used the world over—Ed Markey and Ted Cruz deserve to win this battle. As much as I hate giving Ted Cruz a win.


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Ernie Smith

Your time was just wasted by Ernie Smith

Ernie Smith is the editor of Tedium, and an active internet snarker. Between his many internet side projects, he finds time to hang out with his wife Cat, who's funnier than he is.

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