AM Radio Was Saved In Cars Twice: Can We Do It Again?


The AM debate is fiercer than ever, as EVs stand to cut out the band on the grounds that EV operations create too much radio frequency interference for AM to be viable.

David Schutz, of Hoffman Schutz Media Capital, reached out to Radio Ink with a history lesson for broadcasters. Schutz started out in radio as a broadcast engineer and says that this isn’t the first (or even the second) time that automakers have faced AM interference. So how did radio win the first two battles and can we use that lesson today?

Radio Ink: When did the AM band troubles start?

David Schutz: One of the situations that confronted the industry with the introduction of AM radios in the ’20s and ’30s was interference from automobiles’ ignition systems. Automobile manufacturers had to take six volts of direct current and create a high voltage current that can bridge the gap in a spark plug and ignite the fuel mixture in a cylinder.

This created a monumental problem for AM radio. The radio frequency interference from the electrical system would ping the radio. The interference was unbelievable. It would change frequency depending on the speed of the engine. But there was another type of radio service that the automobile manufacturers were very concerned about – a service other than broadcast radio. That was the early introduction of police radios. The ignition systems interfered with the very early police radio systems.

Radio Ink: Ah, so then it becomes a public safety issue, which is an argument we’re all very familiar with today. So how did they fix it?

David Schutz: To quiet down their ignition systems, they came up with two really good solutions. It was the introduction of something called radio-suppressive spark plug wire. It was a specially insulated cable that quieted things down to very acceptable levels. This was driven home to me as a teenager when I was trying to help a friend rebuild an old car. The ignition harness was short so we just thought we’d use the cheapest thing possible which was ordinary spark plug cable – great on a tractor where there’s no radio, but on a car you had this annoying ping without the resistance and the radio shielding.

Radio Ink: Was it purely the fact that police cars needed functional radios that got automakers working on a fix?

David Schutz: The automotive industry realized they could sell a lot of police cars, but they could also add radio as a desirable accessory. Radio was a money-making source, so there was a true incentive for automakers to want to make radio compatible with cars. It also meant that they’re selling a lot of cars and or trucks in rural areas which by their definition are going to have only weaker radio signals. So the suppression has to be very effective.

So AM radio in cars was saved. And then it happened again.

In the 1960s, American automobile and truck manufacturers changed from traditional generators to alternators. That produced a phenomenon on AM radio in cars that became known as alternator noise. Again, it was motor-speed-dependent, but it was different than the ignition sound. It was more of a hiss. I can still remember in the 1960s, aftermarket products being sold to quiet the alternator hiss.

Radio Ink: If people were buying fixes for the problem themselves, how were automakers compelled to fix this the second time?

David Schutz: Again, it was market forces that compelled them. People wanted AM radio. Automakers had a big problem suppressing that noise. It took an additional filtration system clamped on the back of an alternator where the power came out to further suppress the interference. It became standard equipment.

So that’s a second example of the industry modifying its technology to accommodate interference with the AM signal.

Radio Ink: And here we are again.

David Schutz: History never repeats itself, but it’s got a tremendous tendency to rhyme.

Radio Ink: Some EV makers are working on shielding their cars so that AM works just fine. For the rest, do you think it’s just a matter of cost-cutting?

David Schutz: Absolutely, it’s cost-cutting. At this point in time, Tesla is the leader in terms of raw innovation and integration. They have engineered so many critical systems. My guess, and I don’t have any basis for expert opinion, is that AM interference was so low as to be non-existent in their design criteria. It probably just got overlooked.

And right now, what is the economic motivation to fix it? The only motivation is consumer demand and government regulatory demand. The same way you build in physical safety. There are governmental regulations for the physical safety and structural integrity of all automobiles under the Highway Safety Authority.

But broadcasters were asleep at the switch about AM beginning 20 years ago when they did not protest the fact that the automobile manufacturers were taking the AM portion of the radio units in their vehicles and narrow banding them.

Radio Ink: Okay, but not only was AM radio the only game in town for car audio back then, but it was also an optional extra. It was a moneymaker for the auto industry. That’s gone away now. The moneymaker is going to be subscriptions. They want you to pay monthly for your heated seats and have a Google dashboard.

David Schutz: I saw your story about GM giving the boot to Apple CarPlay. The dash is gonna go to the highest bidder. Even Google may get tossed out. That’s why they’re moving away from CarPlay and Android Auto because they don’t want Bluetooth. It all goes through them. I call it the shaver analogy, i.e., you give away free shavers to sell the blades. You sell a computer printer below the manufacturing cost because you’ll make it up on the ink.

Broadcasters have to be careful not to tread on performance royalties, but you know, maybe broadcasters have to consider that to have over-the-air tunability, we have to buy in and make radio an in-car subscription. I don’t think anybody has brought that concept up, everybody’s probably far too scared of it, but maybe that’s the way we have to play the game going forward.

So you think we have to make radio more profitable for automakers?

David Schutz: For decades, we’ve given away free radios. Now the radio capability may have to be paid for, the same way BMW wanted to sell subscriptions for heated seats.


  1. However, exploring new avenues to make radio more profitable for automakers could be a way to secure its place in the evolving landscape of in-car entertainment.

  2. I have no problems listening to the radio on AM in the car! In one of my cars from 1997 and an other one from 2020, did not interfere with the AM dial. Another thing is urbanized infrastructure – has caused strong noise interference for the AM band! This problem is much more serious! We should solve the problem of switching to digital broadcasting as soon as possible!

  3. I’m watching an Atlanta Braves game, watching the faithful do the “Tomahawk Chop”, and I wonder what Cleveland fans are doing now. Mr. Schutz is really right on in his assessment of the issues facing AM radio, but it’s also affecting radio in general. My Braves story has to do with a lot of what the FCC is doing (or not doing) in regards to its own rulings. Some issues are being addressed by the Washington commissioners but others (like the rules they created decades ago as in Parts 15 and 18) are being ignored.Apparently FCC certification is an option rather than a requirement.

    True that narrow band AM receivers did a lot to affect the overall clarity of AM programming. It happened in my 73 Toyota AM/FM receiver, but not in my 74 Toyota AM only receiver. Yes the AM/FM tuner was an extra option but apparently a ploy to sell more AM/FM receivers. This was MUCH MORE than 20 years ago. A 91 Infinity had a narrow/wide band button it making AM stations sound as good as FM. HD radio in my current Toyota is usually of better quality than analog FM. When you can receive it. Adding to the FM band to accommodate today’s AM stations will cause great economic harm to those currently making money on the AM side. I know there aren’t many but “moving” them to a currently unavailable band can only hurt.

    The final question-will AM radio ever have an abundance of worthwhile mainstream programming again? Conventional wisdom says no one listens to radio at night, so there’s a lot of duplication among stations. Red-Eye Radio. Coast-To-Coast AM, reruns of other shows. Did ya ever think that no one’s listening because there’s nothing worthwhile to listen to? I could go on and on (and usually do) but as Mr. Schutz rightfully points out, broadcasters fell asleep at the controls back then.

    Sirius/XM shows up in new cars sometimes with free subscriptions. That’s not a favor that the car makers are doing for Sirius. Same with Apple Car Play and Spotify and dozens of other apps and services. Is broadcast radio working with car manufacturers to make sure AM/FM exist in the dashboard of the future or are they just hoping that there’s a “radio legacy” that will exist forever?

    The mobile entertainment pie is being split more than ever. May the best product(s) win. Let’s hope radio can bring home the best product. They’ve had practice for over a century.

  4. Jay Rudko is correct. As a group made only of Lawyers concerned about what job they get when they leave the Commission, the ever-sleepy FCC needs to wake up and re-purpose TV channels 2-6 (54-72/76-88MHz)to FM broadcast. And they need to enforce FCC part 15 Unintentional Radiators on the auto manufacturers, just as they do anyone else. Their uneven enforcement destroys any credibility the Commission had in the past.

  5. The FCC messed up by allowing the AM band to become so overcrowded. The poor audio quality is due to receiver manufacturers, trying to cope with the mess. I suggest a rwo-fold solution. Many AM stations are being rebroadcast on FM, either by low-power translator, or on an HD subchannel on an FM station. That’s also happening now. I would 1) look into deleting low-band VHF from TV, reassigning to an expanded FM band. Any TV station on that band would be allocated a new hi-band, or UHF, channel, or could team up with another station to share transmitting facilities. 2) Require HD Radio to be included on all new car, portable, and home receivers. All-digital AM, or hybrid analog/digital signals would also be compatible with those receivers. HD Radio is a free service, and does not require a subscription.

  6. In 1959, the FCC directly ordered television manufacturers to incorporate UHF channels in their products or the sets could not be sold in the USA. The WORTHLESS leadership of the FCC should wake up, smell the coffee, and order auto makers and other automobile receivers to incorporate AM reception, retrofit new vehicles without AM radio, and stop the sale of non-AM band automobile receivers in the United States. AM broadcasters are paying FCC regulatory fees and they are NOT getting support from the Commission. Maybe some good lawyer should file suit and get regulatory fees for AM broadcasters thrown out since the Commission abandoned them.

    • Congress ordered the FCC to require that all TV sets sold in the United States include UHF tuners. The legislation was called the All-Channel Receiver Act. It was inspired by the failures of large numbers of UHF stations in the late 1950s and early 1960s. When the FCC opened the UHF band to commercial television in 1952, the market was already saturated with TV sets that could only receive VHF. Crude UHF tuners, poor sensitivity, and free space attenuation on those higher frequencies also hurt UHF, although some markets, such as Scranton/Wilkes-Barre, PA and South Bend, IN had no VHF stations and were “UHF islands”. The UHF stations survived there in the absence of VHF competition. An All-Channel receiver act should be revived for radio, requiring car manufacturers to include both the AM and FM bands and to improve the quality of the AM section to provide greater fidelity. If you have ever listened to the modulation monitor at an AM station, you can hear what AM is capable of. And Congress needs to press the FCC to enforce Parts 15 and 18 of its rules in order to eliminate a lot of the noise and interference from electric vehicle systems, power lines, and other things that trash the AM band.

      As for the two AM stations that have translators (mentioned by Trey Stafford, below), with the AMs being off the air for several weeks: That is a violation of FCC rules. If the parent station goes off the air, the translator must be shut down. If “Uncle Charlie” decides to visit Arkansas, that owner can expect an NOV and maybe some hefty fines.

  7. I am so perplexed by the AM Radio discussion. Obviously, since my career started at nine years old in 1971 at a 250 watt AM station, there is a lot of emotion tied to my thoughts about AM.

    However, I must share a story. A friend and I were driving through my town of Jonesboro, Arkansas a few weeks ago. He’s in TV, I’m in radio, but we are both broadcasters. I said to him as I hit the BAND button in my Explorer “let’s listen to some good ole AM.”

    We scanned. And listened. And scanned. And listened.

    It was. In a word. Embarrassing.

    The number of signals actually on the air is low.

    The ones that are? Oh, my.

    My competitor in town has two AMs with translators. The two AM signals were off the air. And my friend said they had been off the air for several weeks. He has obviously waved the white AM flag in favor of the FM translators.

    I realize in bigger markets, St. Louis KMOX comes kind, there are exceptions. My company has several markets with strong AMs. And my late CEO, like me, was incredibly nostalgic when it came to heritage AMs.

    But my personal listening experience in my own market makes me ask – what are we saving? Are we saving the nostalgia, the emotion, saving on principal? And if we are going to shout to save, maybe we should make sure we are on the air, and sounding as strong as we can.

    Thanks for the discussion.

  8. Sounds like the time has come for AM to bite the bullet and convert to all-digital or analog-digital hybrid. Our KPLS, 1510 Denver, will start with hybrid within 12 months.


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