why can not receive FM radio on bandscope version??

[muhansarang74]

Hello.

I am curious why the bandscope version (without FM broadcast support) cannot receive FM radio. Even when I enter a valid radio frequency(eg. 107.7Mhz, SBS radio in Korea) in the F1 band VFO, I cannot hear the radio (it makes some strange sounds, but they are unintelligible). It would be great to use both features (spectrum function and FM radio reception), but it seems I have to give up one.

Simply thinking, by setting the radio frequency (eg. 107.7Mhz) and the modulation mode to FM, it should be received regardless of Wide/Narrow.."

I am asking because I lack technical background.

P.S.: Of course, the FM radio works perfectly in the FM broadcast version.

[prokrypt]

Flash/storage size limitations. FM broadcast is "extra wide" and needs to initialize/use a separate chip to receive.

[armel]

Hello,

@prokrypt gave you the right answer.

Armel, F4HWN.

[sgc-fireball]

Hi @armel and @prokrypt ,
I can received FM Radio signals but it sounds very interputed.
For example the UV-5R can received with the original software without issues. If I understand it correctly the software could not initialize the correct chip at this moment?
THX for your work and answer!

[armel]

Hello @sgc-fireball,

Which frequency, which antenna? Tell me more.

Armel, F4HWN

[sgc-fireball]

Hi @armel,

default antenna from the Quansheng uv 5r plus.
My location is Duisburg and the fequency is FM 106.70. The Radio channel name is 1Live.

Here a little video for a hopeful better debugging / discussions:
https://photos.app.goo.gl/qdfrudAgu3dFzJVT7

Richard

[armel]

Hello Richard,

It's very simple: you cannot listen to FM broadcast while in VFO mode. The BK4819, the radio chipset used here, does not support Wide FM demodulation.

As you did with Egzumer, you need to switch to Broadcast FM mode by pressing and holding the 0 FM key (or F + 0 FM). In this mode, the BK1080 chipset is used instead. It is specifically designed for Wide FM demodulation, so you'll be able to hear the stations clearly.

Note: FM broadcast is only supported on the Broadcast and Basic editions of my firmware. If you're using the Bandscope or RescueOps edition, it won't work due to memory limitations.

Armel, F4HWN.

[sgc-fireball]

Hi, oh Sry that was my fail.

But why is the FM spectrum limited to 64-76Mhz? Normaly it is limited to 108Mhz.
https://de.wikipedia.org/wiki/Liste_der_UKW-H%C3%B6rfunksender_in_Deutschland

Greets
Richard

[armel]

Hi,

As for the Broadcast FM frequency range, that's because you don't read the documentation.
There are different frequency ranges in different parts of the world.
Press and hold the 1 Band key to select your own.

Armel, F4HWN