Hi there, I'm very new to working with microcontrollers and ICs and so on. Therefore, I don't even know how to search for the proper chips for my needs.
I read through all 6 pages of search results for "fm receiver" in this forum, and I've tried with Google. Everything I find is
either standard FM receiver 76 up to 108 MHz (e. g. TEA5767)
or AM 433 MHz TX and RX modules
Both TEA5767 and the 433 MHz modules would be about $2. I'm looking for something (hopefully similar cheap) to receive FM audio at a frequency of about 170 MHz. Bandwidth should be somewhere between 20 and 400 kHz. I think the sample rate shouldn't be less than 22050 kHz. I'd like to use my Arduino to control the receiver and then feed the audio to my PC soundcard Line-In.
Yes, that's exactly my problem. I just cannot find a chip for that frequency...
Peter_n:
Some scanners have no problem receiving 87 to 180 MHz, for example the Maycom Ar108.
But you can't control it with an Arduino.
That's true, yet not really what I planned to do. Furthermore, every scanner costs a lot more than $2.
Peter_n:
Since you use a computer, did you try SDR ?
Yes, I know about this possibility. Works great! Yet, I'd like to learn something new (the USB dongle works kind of out of the box, where is the fun in that?), so I thought about a smaller version SDR with a small range of frequencies (170 MHz to 175 MHz), which would be exactly what I need. So I looked into FM receivers, found the TEA5767 and concluded that there had to be a receiver for my frequency. Just couldn't find any and came here to seek support.
Peter_n:
I doubt if there are modules for 170MHz for the Arduino.
But that can't be true, right? No, seriously: can this be true? Is there no demand for this kind of chip?
Maybe I can modify the signal to work with an existing chip? Say, somehow tweak 156-188 MHz down to 76-108 MHz, so the chip can use it? :~
Sorry, I can't find it. A small module, not too expensive, digitally controlled, for 172MHz.
My knowledge of RF is not enough to adapt an existing module for that frequency.
I don't think you will find a chip that does that.
However look at ham radio sites, there is a ham band at 145 MHz and the techniques they use to convert chips to operate in that band will apply to your bands.
It should be a matter of using a differant crystal and altering a few capacitor values.
Please, don't apologize! Seems like we hit the same wall. Thank you so much for searching.
Grumpy_Mike:
However look at ham radio sites, there is a ham band at 145 MHz and the techniques they use to convert chips to operate in that band will apply to your bands.
Do you by any chance happen to have a link? Couldn't find anything searching for "arduino convert modify ham radio 145 mhz"...
Couldn't find anything searching for "arduino convert modify ham radio 145 mhz"
That is hardly surprising.
You just want a schematic with a chip you can control, it is unlikely that any one has used an arduino for this, but once you have a design using an arduino specifically is trivial.
The words:-
ham 2M band RX schematic
are more likely to yield results
