finnbo11
Posts: 3
Joined: Mon Jun 11, 2018 6:19 pm

Radio Receiver

Mon Jun 11, 2018 7:06 pm

Hi forums!
I'm a complete beginner at raspberry pi and I'm very very slowly working towards creating a pipboy from fallout. I want to start with trying to get a radio working on its own. I've looked at a few tutorials but I can't get what I want. I want to use a tea5767 chip as it has an inbuilt amplifier. Cutting to the chase I want to be able to change the frequency with a potentiometer but then it also display the frequency in a window. Please can someone help!?!?!

User avatar
Z80 Refugee
Posts: 162
Joined: Sun Feb 09, 2014 1:53 pm

Re: Radio Receiver

Tue Jun 12, 2018 8:15 am

finnbo11 wrote:
Mon Jun 11, 2018 7:06 pm
I want to use a tea5767 chip as it has an inbuilt amplifier.
I've had a quick squint and the examples seem to be for Arduino. Be aware that the Arduino used 5V but the RPi used 3.3V (even if 5V is available from the GPIO and USB etc). You will need to make sure the electrical interface is OK (or adapted) for communicating between the RPi and the TEA5767 module, but otherwise anything you can do with an Arduino should be possible with an RPi. I say "should be", because the Arduino is just a microcontroller, so it runs your code and that's all, but the RPi usually runs a full-blown operating system so there is all sorts of stuff going on all the time and you have to be careful if you have critical timings.

That said, serial communications are handled with hardware so it shouldn't be a problem.
finnbo11 wrote:
Mon Jun 11, 2018 7:06 pm
Cutting to the chase I want to be able to change the frequency with a potentiometer
That won't be so easy. There are no analogue inputs on the RPi, so you will either need an external circuit to do it (HAT) or think of something else. A rotary encoder may be the way to go, so that the shaft rotation is fed into the RPi as a series of pulses which you read in a program to control frequency. All you need to do then is send the frequency to the radio module and display it on the screen.

finnbo11
Posts: 3
Joined: Mon Jun 11, 2018 6:19 pm

Re: Radio Receiver

Tue Jun 12, 2018 10:41 am

I've done a bit of work with Arduino. Is there anyway I could feed data to the RPi. Or alternatively is there another similar chip I could use?

User avatar
Z80 Refugee
Posts: 162
Joined: Sun Feb 09, 2014 1:53 pm

Re: Radio Receiver

Wed Jun 13, 2018 9:40 am

finnbo11 wrote:
Tue Jun 12, 2018 10:41 am
I've done a bit of work with Arduino. Is there anyway I could feed data to the RPi.
Plenty. A standard serial data link seems favourite.
finnbo11 wrote:
Tue Jun 12, 2018 10:41 am
Or alternatively is there another similar chip I could use?
For what?

finnbo11
Posts: 3
Joined: Mon Jun 11, 2018 6:19 pm

Re: Radio Receiver

Wed Jun 13, 2018 10:08 am

finnbo11 wrote:
Tue Jun 12, 2018 10:41 am
Or alternatively is there another similar chip I could use?
For what?
[/quote]

I mean a similar radio chip that is fully compatible with RPi

LTolledo
Posts: 64
Joined: Sat Mar 17, 2018 7:29 am

Re: Radio Receiver

Wed Jun 13, 2018 10:15 am

finnbo11 wrote: Or alternatively is there another similar chip I could use?
maybe you're referring to bi-directional level shifter?

https://www.sparkfun.com/products/12009

pksato
Posts: 282
Joined: Fri Aug 03, 2012 5:25 pm
Location: Brazil

Re: Radio Receiver

Wed Jun 13, 2018 11:49 am

Hi finnbo11,
You need to be more clear about you needs.
I don,t know other FM module that use other chip.
SiLab have a series of broadcast radio chips, but, I don't know if have a cheap modules using it.
I find one: https://www.sparkfun.com/products/12938

tea5767 can power from 3V to 5V, can be connected on 3v3 from RPi. Not need voltage shifter.
You need to write lots of code to put this module to work, and display frequency on main screen or small LCD display.
tea5767 is a digital tuner, need to send a command do change frequency, potentiometer is not a better choice for this task.
You can use a rotatory encoder to change change frequency, or two push buttons.

I found this article about using tea5767 fm module.
https://www.linuxcircle.com/2015/08/17/ ... rt-1-of-3/

Oh, have a kernel module to tea5767, you can use any /dev/radioX compatible software to tune you favorite FM station. Software like fmtools, vlc, etc.

User avatar
Z80 Refugee
Posts: 162
Joined: Sun Feb 09, 2014 1:53 pm

Re: Radio Receiver

Wed Jun 13, 2018 12:20 pm

finnbo11 wrote:
Wed Jun 13, 2018 10:08 am
I mean a similar radio chip that is fully compatible with RPi
There's nothing "incompatible" about the TEA5767 - I just told you to make sure it would be OK running at 3.3V instead of the Arduino 5V, and the post above says it is. The rest is learning how to code the RPi to run it.

The only real problem left is that you want to use a potentiometer to input the frequency setting to the RPi code. From this, I assume you mean you would like a traditional tuning dial, using a potentiometer to measure the position of the dial.

This isn't a great idea for several reasons: first, with no analogue input on the RPi you would need some kind of circuit to take the voltage output from the pot and convert it to digital form to feed into the RPi. Second, the pot itself will produce a "noisy" output and may not be repeatable over time, which doesn't matter too much when an audio volume varies slightly but will matter a great deal if you expect your radio to remain tuned.

I guess you don't know what a rotary encoder is. Basically, it's a device in a similar package to a potentiometer, but it contains switch contacts which make and break when you turn the shaft. These switch signals can be fed directly into the RPi's digital inputs, and counted to know what angle the shaft is at. The typical ones are motion sensitive rather than position sensitive (you can't tell where it started from, but you know how much it was turned and in which direction). There are absolute position encoders, but they are more expensive.

There is a current topic about rotary encoders here: viewtopic.php?p=1325495#p1325495

Return to “Beginners”

Who is online

Users browsing this forum: Convert, ghans, jmellars, klricks, SmartySmart702, The Traveler and 66 guests