Why no built in FM transmitter?

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  1. bbuck002

    bbuck002 Well-Known Member

    not only does the FCC differentiate between devices, they also differentiate between transmission frequencies. I know this from having hand held two way radios and also from back in the day of cb radios. it mainly comes down to money. In order to transmit on certain frequencies you have to pay the FCC for a license. They have spectrum open for public use, however, its the crappy end of the spectrum that is transmitted by line of sight only.
    B/c radio waves comprise a range of freq. they regulate them differently.

  2. bbuck002

    bbuck002 Well-Known Member

    i'm not saying that the manufacturer's couldn't put in fm transmitters if they wanted to. that doesn't mean the FCC wouldn't regulate it, but they already regulate everything else having to do with these devices anyways.
    it could be something as simple as the amount of space it would require in the device to accomodate a FM transmitter. I know these are do almost anything devices, but they are limited to their thickness, battery consumption, and at present already have several radio transmitters in them. one for wifi, one for cell, a gps chip. i'm guessing that somewhere along the line someone in design said, we want all the functionality we can get, but what can we do without to make the devices as slim as people want them.
    i'm just hypothesizing right now, but this seems to be just as logical a reason for no FM transmittor than others.
    as for bluetooth transmission of music, from what i've read on this forum, that sounds to me to be the worst way to transmit the signal. when it comes to music, for me, it's all about how faithfully i can reproduce the sound. and the best way to do that at present is still with a heavy gauge cable. much less compression and decompression of the signal needs to be done, meaning higher fidelity.
  3. colornshape

    colornshape Well-Known Member

    I don't understand your first sentence. Maybe it relies on generational slang with which I am unfamiliar, or contains some key mispellings that make parsing it impossible for me. No matter. My point was that your use of "sir" is almost universally recognized to convey derision or disdain. I really wasn't offended, but I saw no reason to let it pass.

    I think at this point, now that we've covered possible reasoning behind the manufacturer's failure or refusal to include this functionality, it would make more sense to move on.

    Does anybody know if an app could be written to do this? It is no secret that some apps are able to control the phone's ability to transmit radio. Barnacle and Wireless Tether, for example.

    I suppose no developer sees enough demand. I know I could learn to write in Android and make my own app, but that requires a time commitment beyond what I can justify.

    This, after all, is just a relaxed, casual conversation about extending the usefulness of devices that most of us could live without.

    I am grateful for your replies and for your sincere attempt to contribute to the thread. Swords are made by hammering them, and so are sharp minds.

  4. PACAnesFan

    PACAnesFan Well-Known Member

    I don't think so. The X has a FM receiver that uses a headphone cord as an antenna. I don't think the X has a FM transmitter within, even if the software could be written.
  5. colornshape

    colornshape Well-Known Member

    If accurate, that clarifies things a bit. I thought that since these devices all used radio for everything that they could simply use the onboard transmitter for whatever frequency they wanted. If that is actually impossible because of the hardware, then the question is answered.

    Also, my Bluetooth receiver/FM transmitter produces really high quality audio. Sure, it's not as good as using a cable, but I doubt many people could tell the difference.

  6. PACAnesFan

    PACAnesFan Well-Known Member

    I have a pair of Moto S9 Bluetooth headphones. Not bad audio quality. Good for gym workouts so you don't have to deal with wires around you. No way audiophile though.

    I am using my X with a pair of Seinheiser HD555s, due to the low impedance of them. The X seems to drive it fine. I wish the X had a line out jack, so I get get myself a quality headphone amp.
  7. quickaudi

    quickaudi Well-Known Member Contributor

    Well, again, our X comes with wifi, bt, 3g, 1x - all of which are send/receive mediums by nature. (Wouldn't make sense to have a phone that you could only listen to...)

    However, FM reception requires our phone to have an external antenna attached, and knowing the size of electronics required (think of how big the one you use is) and the battery hog that a transmitter can be, our phones just don't package that size very well.
  8. colornshape

    colornshape Well-Known Member

    It would be interesting to compare the power consumption, range, and data density of the X's WiFi Hotspot function to that of a standard Scoche or Belkin FM transmitter. Wonder if that information is available somewhere...

    I've had a couple that would work for many hours on a single AAA battery. Or maybe two.
  9. quickaudi

    quickaudi Well-Known Member Contributor

    If only there were a way to globally connect a bunch of computers to connect information so that I could share the answer with you...


    Simple 30 meters range FM transmitter

    Note: the power consumption isn't bad for 30m, but the sheer size of the transmitter isn't really feasible in a thin phone.
  10. colornshape

    colornshape Well-Known Member

    Yeah. I saw other stuff like that. Those seem to be intended for low cost, DIY projects. I think the mojo way to get a definitive answer is to ask a manufacturer. I had hoped to avoid that, since they're generally unhelpful and slow to respond.
  11. bbuck002

    bbuck002 Well-Known Member

    yeah you will probably just get a form letter response to this kind of question from moto.
  12. quickaudi

    quickaudi Well-Known Member Contributor

    well, why not try posting up on the moto forums?
  13. colornshape

    colornshape Well-Known Member

    Yeah, I'm going to try the developer forum when I get a chance. I'll report back he anyone's interested.
  14. Napalm

    Napalm Well-Known Member

    You mean an FM transmitter/modulator for your car stereo. long answer short, they are used so rarely by people that nobody would pay for the item and carry its weight in the device with all the other martketable features.

    Now yes you can get modulators that standalone, for the people that need them, this is perfect and works wonderfully. They draw quite a bit of power, hence why they typically plug into lighter/power adapters.

    This is why your phone won't have one. BT takes much less power as its a discrete digital signal and much weaker than analog FM for similar coverage distances.

    FM analog has to have the power to push through interference.
  15. colornshape

    colornshape Well-Known Member

    So the phone can transmit in the 2-5 GHz range, but not the 87-108 MHz range? Bummer.
  16. Napalm

    Napalm Well-Known Member

    yes. more or less.

    that 87-108mhz transmitter, can only be 10 watt or less without a license from the FCC. (IIRC). meanwhile, the other transmitters on the DX is 6 milliwatts or less.

    major difference in scale. also your FM antenna needs to be significantly longer (due to frequency and wavelength) than a cell, cell data, or BT antenna.

    BTW, old timey bag and car analog cell phones, were 6 watt transmitters.
  17. colornshape

    colornshape Well-Known Member

    So those small, self contained cigarette lighter units have a coiled antenna or the equivalent?
  18. Napalm

    Napalm Well-Known Member

    yes, usually or the power cord wire is the antenna line. Like the power cord of the Sirus radio unit you can buy at Walmart for $60.

    or te Belkin ipop fm adapter that charges the pod while broadcasting a signal to the radio. the antenna is in te back of the ipod stand.
  19. colornshape

    colornshape Well-Known Member

    Many thanks for jumping in. It was pretty frustrating when I thought the phone was just crippled. The fact that it would actually require a costlier design makes the absence of this feature easier to accept. It is baffling to me that I seem to be the only one who wants this, though. It seems odd that most people rely on three hundred year old technology when there is one hundred year old tech can be used.

    Ah, well. Thanks again, and to the rest of the contributors.

  20. bigbadwulff

    bigbadwulff Well-Known Member

    You are not alone. I would love the FM transmitter. As I said earlier I really dislike having external items that can be lost/misplaced/be in another car/etc.
    To me this is like saying using an ethernet cable is better than having a wireless router for internet use on a laptop.
  21. colornshape

    colornshape Well-Known Member


    I still can't buy a dash mount with an inductive charger, but at least I know I'm not alone here. The world isn't totally senseless, after all.
  22. PSkeptic

    PSkeptic Well-Known Member

    It's pretty easy why you wont find a phone that has an FM transmitter inside of it:

    The FCC has ruled in the past couple of years that any device that transmit on a licensed band (Cell freqs) can not transmit on an unlicensed (Or, actually, "licensed by rule" is the FCC term) band.

    It has nothing to do with required antenna size, since your Part 15 FM-band device must have a terrible antenna in order to comply with specs( 25 uV/m at 3m distance, might be incorrect on the 25, but it's a tiny amount).

    Add to that, if by some chance you WERE able to squeak it by the FCC, your phone now must meet ANOTHER round of testing, to ensure it will not cause "Harmful Interference".

    Now, that being said, I can not for the life of me fathom why it would be so difficult to use a COTS Part 15 FM device attached to your phone, or a car dock solution connected to the FM stereo with one of these:
    Scosche Universal FM Modulator FMMOD02 - Car FM modulator

    You can't beat that, it's damned near direct cable to your stereo, and only an audiophile would notice. But, they'd noticed your compressed audio before that.
  23. colornshape

    colornshape Well-Known Member

    I use a stand alone transmitter. I know it's not exactly what you're talking about. It's an inelegant and inconvenient method. I wound prefer a more sensible solution. It's disappointing that a bizarre, double standard law prevents that.
  24. bigbadwulff

    bigbadwulff Well-Known Member

    Well it's the same "logic" that kept/keeps VW from importing cars that get 50 mpg. Friggen stupid control insanity. The sooner we get the control freaks out of Washington, the better.

    We have 2 of the VWs that were imported before the stupids laws were introduced and will have them until they rot.
  25. colornshape

    colornshape Well-Known Member

    "One of the greatest delusions in the world is the hope that the evils of this world are to be cured by legislation." Thomas Reed

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