No AM Radio on 3 (Like the X)

[wdolson]

I'm sure I'll be dating myself, but I do remember the am to FM converter when cars only had AM. I wonder if they will make an FM to AM converter. for the 3.

Found on ebay:

View attachment 253710

The market will probably be small because so many stations are streamed these days.

I wonder why the Model X doesn't have AM. The Model S does, or at least it's in my 2016.

Some EVs don't have AM radios to cover up an electrical noise problem. Pulse Width Modulation motors create tons of electrical noise and a lot of it is in the AM band. If you want to find a PWM motor running somewhere, get an AM radio and walk around with it, as you get closer to the motor the noise will increase. You can also find noise induced onto other circuits from PWM motors with an AM radio.

The BMW disabled the AM band in the i3 because of the noise from the motors drowned out the band entirely. Someone has a video on YouTube where they re-enabled the AM radio on an i3 (the radio unit is the same as on some other BMW cars) and you can see why BMW disabled it. The aluminum body of the Model S acts like a good enough Faraday Cage to screen out most of the EM noise from the motors. Or they did something else to filter out the noise? I can hear a slight whine on AM when accelerating, but not much.

Maybe something about the X and 3 lets too much noise in? It's odd the X would have AM disabled and the S wouldn't.

 

[ahagge]

Much as I dislike the exclusion of AM, I suspect it's another "cost cutting" move on Tesla's part. An FM tuner is built into many LTE modems, so the capability likely came "for free". Not so with AM radio (or HD Radio, which is the other technology that I'd love to see implemented).

Sigh.

 

[ProphetM]

The market will probably be small because so many stations are streamed these days.

I wonder why the Model X doesn't have AM. The Model S does, or at least it's in my 2016.

Some EVs don't have AM radios to cover up an electrical noise problem. Pulse Width Modulation motors create tons of electrical noise and a lot of it is in the AM band. If you want to find a PWM motor running somewhere, get an AM radio and walk around with it, as you get closer to the motor the noise will increase. You can also find noise induced onto other circuits from PWM motors with an AM radio.

The BMW disabled the AM band in the i3 because of the noise from the motors drowned out the band entirely. Someone has a video on YouTube where they re-enabled the AM radio on an i3 (the radio unit is the same as on some other BMW cars) and you can see why BMW disabled it. The aluminum body of the Model S acts like a good enough Faraday Cage to screen out most of the EM noise from the motors. Or they did something else to filter out the noise? I can hear a slight whine on AM when accelerating, but not much.

Maybe something about the X and 3 lets too much noise in? It's odd the X would have AM disabled and the S wouldn't.

Perhaps with the huge cutouts for the rear doors, the Model X does not act as a cage as effectively as the S. And if it's the aluminum that is doing that, then maybe that's your answer for why AM is missing on the 3 - much less aluminum.

 

[wdolson]

Much as I dislike the exclusion of AM, I suspect it's another "cost cutting" move on Tesla's part. An FM tuner is built into many LTE modems, so the capability likely came "for free". Not so with AM radio (or HD Radio, which is the other technology that I'd love to see implemented).

Sigh.

The Model S and, as far as I know, the Model X has HD.

Perhaps with the huge cutouts for the rear doors, the Model X does not act as a cage as effectively as the S. And if it's the aluminum that is doing that, then maybe that's your answer for why AM is missing on the 3 - much less aluminum.

It's tough to say for sure. The Model X has more glass and less aluminum on top, that might contribute. The Model S only comes with a glass roof now, but mine has the solid roof, which would shield better. Steel is not as good at absorbing EM noise, but it would absorb some.

Car glass can be made to filter EM, my Buick had it which made using the garage door opener through the front windshield tough, though the side windows were not shielded and holding the opener up to the driver's side window worked. Sometimes I would open the window and hold the opener up from up the street. This was the norm when I stopped to pick up the mail from the neighborhood kiosk which is about 4 houses up the street.

The front window was treated with stuff to only allow visible light through. It cut off in the infrared and ultraviolet spectrums to protect the dash from UV and cut down on solar heating in the summer. It worked pretty well on the UV, the car was 24 when I sold it and the interior looked almost new except for carpet wear.

 

[EVNow]

Not that a $3.85 (shipped) radio from e-bay can't solve ....

Since it is likely coming from China, buy early so that it will come before your 3 comes.

Mini Portable Pocket AM/FM Telescopic Antenna Battery Powered Radio Receiver | eBay

 

[EchoDelta]

The market will probably be small because so many stations are streamed these days.

I wonder why the Model X doesn't have AM. The Model S does, or at least it's in my 2016.

Some EVs don't have AM radios to cover up an electrical noise problem. Pulse Width Modulation motors create tons of electrical noise and a lot of it is in the AM band. If you want to find a PWM motor running somewhere, get an AM radio and walk around with it, as you get closer to the motor the noise will increase. You can also find noise induced onto other circuits from PWM motors with an AM radio.

Do you have other examples of this? I asked around for non-Tesla experiences in our family, the MB Bclass (with Tesla batt+motor),a Leaf and even a rare Plug in Prius all have working AM.

Regardless. It won’t have AM.
Moving on...
Is there a decent digital AM tuner that can forward the audio on via bluetooh or act as a USB audio source, and powered via usb or 12v? To keep in the glovebox for those road situations. I think it may be an interesting trinket like a revival of the am-fm bridge posted before.

 

[wdolson]

Do you have other examples of this? I asked around for non-Tesla experiences in our family, the MB Bclass (with Tesla batt+motor),a Leaf and even a rare Plug in Prius all have working AM.

Regardless. It won’t have AM.
Moving on...
Is there a decent digital AM tuner that can forward the audio on via bluetooh or act as a USB audio source, and powered via usb or 12v? To keep in the glovebox for those road situations. I think it may be an interesting trinket like a revival of the am-fm bridge posted before.

The Model X, 3, and BMW i3 are the only ones I've heard of. Different cars have different types of motors. I haven't done extensive research into the drive electronics for all cars, but I believe PWM is only used with AC motors like Tesla uses. I believe the Leaf uses a permanent magnet motor and may not use PWM. I never studied PWM motors in much depth, and I can think of how a DC motor could be driven with PWM, but I don't think there would be any advantage to doing that.

If the AM radio has been eliminated because of noise, an aftermarket AM radio won't work when driving, though it would work when stationary.

 

[JoeCoolMan24]

As someone that lives in a country where we tend to wait a few years before the newest technology arrives, will AM still be missed? I mean who actually still use AM radio stations, I certainly don't.

Oh I don't know....most of the other people who replied to this thread? Or did you not even read anyone else's posts first?

 

[johnnyS]

I use AM radio to listen to sports broadcasts and news on a regular basis. I would think twice before getting a car without AM

 

[FlyingKiwi]

The Model X, 3, and BMW i3 are the only ones I've heard of. Different cars have different types of motors. I haven't done extensive research into the drive electronics for all cars, but I believe PWM is only used with AC motors like Tesla uses. I believe the Leaf uses a permanent magnet motor and may not use PWM. I never studied PWM motors in much depth, and I can think of how a DC motor could be driven with PWM, but I don't think there would be any advantage to doing that.

If the AM radio has been eliminated because of noise, an aftermarket AM radio won't work when driving, though it would work when stationary.

I think you'll find all common inverters use PWM, it's how they control the current to the motor, regardless of whether is AC, DC, induction or permanent magnet.

 

[wdolson]

I think you'll find all common inverters use PWM, it's how they control the current to the motor, regardless of whether is AC, DC, induction or permanent magnet.

An inverter converts DC to AC. You don't need it for a DC motor. DC motors are usually controlled by adjusting the voltage. PWM isn't used for all AC motors either, though it is pretty much the most efficient way to control an AC motor.

 

[FlyingKiwi]

And PWM is how you control the voltage/current to a brushed DC permanent magnet motor, or at least it is in wheelchair and scooter controllers. You are right DC motor controllers aren't inverters, but they are essentially the same technology.

 

[C_A_Braun]

Adding https://www.amazon.com/dp/B01FX9WTY...t=&hvlocphy=9030773&hvtargid=pla-348533494966 to my Christmas wishlist.

 

[xav-]

No AM radio really???

I am going to cancel my reservation

Is there a CD player at least???

 

[S3XY]

No AM radio really???

I am going to cancel my reservation

Is there a CD player at least???

Don't worry you can still use the cassette player

 

[Candleflame]

When was the last time I used AM radio... hmm... I think it was pre-war, not sure which one though. Maybe WW2?

i think it still has a niche in america and africa as the range is often better and audio quality also a bit better with poor reception.

 

[BioSehnsucht]

Putting aside things like talk radio that worst case scenario you can live without, AM is used extensively for emergency road condition / weather / etc notifications in North America.
Travelers' information station - Wikipedia

FM is common in the rest of the world, but in NA it's mostly FM.

 

[wdolson]

Don't worry you can still use the cassette player

What no 8 track?!

 

[hill]

AM is dying. And with a reason. Quality can not get better. It's worse than FM. And FM is also not awesome.
Why keep old things alive if we have much better things to use. Even FM is phased out slowly. Norway was #1.

From somewhat of a radio geek's prospective, there are two things with AM. first - AM radio stations transmit anywhere from 535kHz to 1605kHz. The FCC has them spaced at least 10kHz apart. AM only differs from FM by the way the transmits. Keeping it baby simple, FM modulates a particular frequency (waves per second) whereas AM's 'amplitude' represents the HEIGHTS of the wave ... so it gets stronger when the wave is taller ... but the amplitude wave can be set to more than the space the FCC provides for your AM radio.
What this means is, you COULD send a digitized HD signal signal on 640AM ... you just wouldn't hear it with your regular AM radio. In fact, that's how many FM HD radios can transmit 2 or more signals on the same part of their FM slot ... because it's digital. All that mumbo jumbo said ... don't write off AM just yet - because it too has tons of digital potential.
BTW, my favorite Kenwood Amateur radio receives great on AM. One fellow in our radio group came across an overturned motorhome out it the most forsaken regions of the Cali desert (no cell service) some 10+ years ago, and he was able to summon emergency help transmitting AM around 1,820kHz for the critically injured. His 100 watt signal traveled all the way back to a station in Oklahoma, and that person phoned it in.
We also have a satelite phone for emergencies - because sometimes AM signals travel well, and sometimes they don't

.

 

[johnnyS]

On my drive to today from Monterey to LA I listened to the Dodgers baseball game once I was in the area to pick up the signal.