Why does the Chinese radio pick up the TV, but the radio in the phone does not?

Question

Mobile devices

(Almost) any Chinese FM radio has a range of 88-108 MHz and at a frequency of ~ 103 MHz (in the range of 102-108) begins to speak with the voice of channel 1. In general, you can listen to TV on it. The FM radio in the smartphone (regular, not internet radio) has a range of 88-108, but does not find channel 1. A conventional radio has a retractable antenna, in a smartphone it has a 2-meter wire from the headphones.
What could be the reason and is there a solution?

Answer 1

Although the question is formulated extremely chaotically, I will try to answer.
Firstly, at a frequency in the region of 103 MHz, there are no carrier frequencies for the sound of any TV channel.
The frequency plan of the audio channels looks like this:

1 -56.25
2 - 65.75
3 - 83.75
4 - 91.75
5 - 99.75
6 - 117.75
7 - 125.75

etc. (Keep in mind that these are not names, but serial numbers of channels.)
So it is the receiver in the smartphone that behaves correctly, and Chinese FM receivers suffer from the effect of "mirror frequencies". If you do not go into the details of the theory of operation of radio receivers, then the point is that when converting a radio signal, it shifts in frequency several times. And this mechanism can cause a similar effect - when you tune to a certain frequency, you seem to receive some kind of signal on it, which, in fact, is transmitted on a different frequency. This is caused by poor mirror frequency rejection, a very common problem with Chinese receivers.
Thus, if you want to receive the sound channel of a TV channel, you just need to tune in to its real frequency, and not catch the DSLRs.
Related links:
TV channel frequencies
Reception of mirror channels as a design flaw ...