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I am looking for an offline FM radio without antenna.

It was definitely possible on older devices with Android Jelly Bean, but I look for a non-root solution.

I know that FM radio requires a 75 cm antenna, that's why the stock FM radio app is forcing me to plug in earphones. But I need another app which ignores this physical requirement.

I see no reason why it shouldn't work for Android 7. But all the offline UKW/FM radio apps I found in Playstore are lying, these are just online radio apps, not using the built-in fm radio hardware.

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  • Try this or this or others - all are from Izzy's lists
    – beeshyams
    May 9, 2020 at 10:00
  • Related: Radio without the headset, How to play FM Radio app without earphone? and also on Quora, Why don't phones have a built-in FM antenna?. The earphone works as an antenna; so without the antenna, I'm not really sure what the FM Radio app will output the sound. On the other hand, your older devices (if we may know) might be an exception having an in-built FM antenna.
    – Andrew T.
    May 9, 2020 at 10:22
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    @AndrewT.♦ it is working fine without antenna with just jack. but my device is waterproof and i don't want to keep open rubber lib seal all the time
    – alecxs
    May 9, 2020 at 13:07
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    @AndrewT. Sorry for the late reaction. There is some antenna in all the devices, inside the phone. FM radio requires a longer one, because its longer wavelength (smaller frequency, typically about 100 MHz, contrary to the some GHz digital signals). This is too much for an antenna to exist in a typical phone size. This is why some solution for an external antenna is needed. However, actually also a shorter antenna could work, but it might decrease the quality (possibly hugely). Getting the FM signal requires some hardware support, this is built into most devices.
    – peterh
    Dec 25, 2020 at 11:35
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    This is essentially an analogous FM signal -> digital bitstream converter. The question is, how is this hardware configured. Possibly it only can use the earphone receiver, but it is not sure. If not, if it bound on the hw-level also with the builtin antenna, then a low quality FM signal read might be possible. Possibly it would require a driver change/reconfiguration. possibly not. Probably the chances are better if the device itself is big ( -> there is more place for the builtin antenna). Probably the quality of the received signal will be bad, maybe very bad.
    – peterh
    Dec 25, 2020 at 11:37

1 Answer 1

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The Redmi Note 9 radio works without earphones plugged in.

Does not do much else like work as a phone but the radio works.

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  • indeed com.miui.fm works without antenna, thx!
    – alecxs
    Sep 9, 2021 at 20:24

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