Can RF Modules be used for Audio Transmission?

Hi All,
Im in doubt about the use of the normal 433MHz RF Modules for Audio Transmission using UART of the microcontroller...
Please let me know if it is possible to do so..

Thanx & Regards.
Sidy

It depends but it is somewhat possible

if the link can support error free 64 Kbps then it is Ok

I suggest the baudrate would be 115200 and the distance should be short to decrease the error as possible

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You can test it your self...

What I will do is, a simple test. ie

PWM the audio signal ---> send it via RF module --> receive it --> use RC demodulator + audio amplifier

But I don't know if it will work or not
PWM is still analog signal..

Now, in case of digital audio transmission, you can have a calculation by considering the maximum baudrate possible on the RF module, number of bits per sample of the audio and the audio sample rate.


Also, I may try to reduce the number of bits/second by using some thing like DPCM etc..

i did it, but the quality is very low.

there are a few things to remember or it will be not possible to do this.

1. these modules are meant to send 0 and 1 for micro controllers, so basically it works as some fast switching device which either transmits 0 or 1.

2. But you will find that in every device which claims to be digital is just a device which goes seemingly switching but to achieve it, there is always an analogue circuitary doing this for it and in every analogue switching its just amplification which when made in such way that it amplifies a very limited section of voltage and seemingly we cannot make out whether it was an amplification.

3. So what i did is i tried to find out this value of voltage on which it works and found that yes, it can be done. I transmitted sngs from my computer output and listened on reciever but the only problem was that the birate rate was very poor obviously because when the voltage fluctuated the in audio input, it would sometimes cross the upper limit and when it went down there was absence of sound.. but yes it can be done.

4. the frequency modulation in this process is very limited and it seems it uses o and 1 as 433mhz and 0 hz(absence of frequency) where as to get a good resolution you need to get 430 - 436 mhz bandwidth limit (this is for example to get an appropriate fidelity). So its not useful in audio transmission but yes you can try for better understanding how digital and analogue devices are so closely bound and what many ways can we understand the properties and how to impart and adjoin the devices.

5. you dont need to convert it to pwm and then do whatsoever was told in previous post, i dont think it would be a good idea. may be you will get a gud quality output then, but these transmitter reciever cannot carry heavy and big data and also micro used will not be able to send and recieve data in that amount and there can be delays and data loss etc. if anyone tries this also please tell me if the results are good. What i said above is just about giving audio signals to the data pin and nothing more.. this would be a completely different thing to do.

you may drop me a mail (deepakjos2000@gmail.com) if have any querries. i rarely come on this site.

there are rf modules that manage fm audio. they are in the same frequency range , but different from data modules.; a sample link is here to understand the specifications at least

https://www.alibaba.com/product-gs/591302406/RF_module_433Mhz_Data_radio_433.html

datasheet says433MHz RF Modules has only 1kbps ,so i think it cant send ..
any other module for this purpose ?
what is the minimum audio bit-rate ?
433mhz module has the bitrate is 422851kb ,is it correct ?
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or how it is related (frequency and bit-rate )