just thought how would a “cool” kit look a like, so I get an altoids tin box eat all the thinks inside and put all necassary parts inside. 😉
I got some of those very popular FM radio modules, and was thinking how to use them.
I found some nice instructables about the TEA 5767 most of them use a NOKIA LCD Display and some buttons to change the frequency or auto scan…., I try those first to learn how to use the TEA 5767, but I didn’t like them so much it was to boring for me just copy another work and so I think what else could I build with such an TEA 5767 and an Arduino plus some other parts.
I like LED’s, to be honest I’m addicted to those LED’s. Trust me everything with LED is funny.
I remember those old FM Radios with an “knob” to turn around for adjusting the frequency and showing the frequency on an bar graph like display.
I owned one long time ago there was the indicator for the frequency was a single LED.
So the Idea was born for my own FM radio….
1. it should use the TEA 5767 Modul.
2. it should be controlled by an Arduino or something similar
3. 2 x 74HC595 to controll 16 LED’s
4. one LED for Power
5. a rotary Encoder
5. 3 – 4 normal tactile switches
Step 1: Get your parts
Here is a small overview which parts you need. I think it is called Bill of materials (BOM)
1 x ATMEL Atmega 328P
1 x 28 pin dip socket
2 x 74HC595
2 x 16 pin dip socket
1 x TEA5767 FM Stereo Radio Module
2 x 5 pin header for the TEA5767 board
1 x 2×3 pin header for the ICSP header
1 x 16MHz Crystal
2 x 22pF Cap
2 x 100nF Cap (SMT 805)
4 x Resistor 10 KOhm
17 x Resistor 220Ohm
4 x Tactile Switch
1 x Rotary Switch
16 x LED’s 3mm red color
1 x LED 3mm green color
Step 2: Schematics
I always start with handwritten schematics, I like them more then starting at the computer and to be honest I’m still searching for a software that I like and do the job.
here are the schematic for the modules and how to connect them to the Arduino board or the single processor, I used the names of an Arduino UNO R3 Board. More documentation will follow soon, if someone would help me with doing the schematic it would be great.
1. 16 LED’s with 2 x 74HC595
2. Switch and Rotary Encoder
3. TEA 7567 Modul and PinOut
4. The schematic for the Arduino standard layout can be found at several places. I just used the Crystal and 2 x 22pf caps, and add the Reset circuit to it.
Step 3: Prepare the perfboard
I always buy the same size ( 90mm x 150mm )
The perfboard I used for this project is a double sided with round solder holes.
1. two boards with 18 for the circuit and the “supportboard”
2. a small board with 8 x 5 holes for the TEA modul
Step 4: Prepare the TEA Modul
For testing I solder the TEA Modules on little perfboards and also add some Pinheader for them. So it was more easy to test them. You can find tones of better tutorials to make them. Soon I will wrote more here after I made some got pictures.
Step 5: Wiring and putting all together
That is how I made it, I just want to explain how I done it and show you some pictures the final product was a little bit messy but I like this “flying” wiring. It is like a signature by me.
I added a picture where you can where I place all the parts so it should be easier if you want to build it.
1. Step just solder the LED’s even it would be better to start with the 220 Ohm resistor but hey while soldering I just place the parts and look how it look call it rapid prototyping -> don’t think just solder it
2. After I solder the LED’s and the resistors I started to place the other parts while this stage I didn’t think so much about where the parts have to go to make it more easy to solder I just wanted that it look “cool” for me, only the 74HC595 I have placed upside down so the “outputs” was near to the LED’s. This is the second picture
3. Next step is to solder the output from the 74HC595 to the resistors now you can already see it is getting messy but don’t worry it will be more worst soon.
4. Go ahead with the wiring for +5V and GND don’t forget to put the 100nF caps for decoupling close to the 74HC595 I used some 805 SMT 100nF Caps they are just laying around in my Part bin and fit very well underneath the board. After you finish this you are close to the final and your board should already look very messy “prey” that you don’t make a bigger mistake with the wiring finding any “bug” is not easy at this stage trust me I know what I’m talking about.
5. at least start with wiring the signal levels from the ATMEGA to the other parts on the board.
– 3 Signals to the second 74HC595
– 2 Signals to the TEA 5767 Modul
– 4 Signals from the tactile switches
– 3 Signals from the rotary encoder
– after you attach all connections your board will look “messy” this is the look we want. Hey this is the look I want maybe not you. But when you are still reading at this position and still with me then you like this look.
6. Double Check before you give power to the board first time, don’t let the magic smoke escape from the chips.
You can put all together on a bread port or build it like me on a double side perfboard I try to build it as small as possible.
With those Pictures I just show how I made it, I’m still try to paint a real schematic, but I can’t find a software I can get used to.
Step 6: First time Power it up
Power ON, now it is time for the first test.
For me this was the longest part I have had no idea about the programming my last try with the AVR IDE was long time ago and writting software with C is even longer time ago, but I have to say using the Arduino IDE with the great community is very easy and so after some evenings I could finish my first software and so one my first “alpha” of the FM radio firmware.
First I copy the boot loader to the board just with my USBAsbp programmer.
This is a short story how I designed the software, I started with some tutorials about the 74HC595 and figured out already some problems I have had with the connections just make some mistakes so writing the software was also a hardware troubleshooting for me. And there was a lot of mistakes at the beginning.
1. Make the 74HC595 running so I could control the LED’s attached to it.
2. Make the rotary encoder running and see what it do.
3. Make the TEA modul running and set a fixed frequency.
4. Change the frequency with the 4 tactile switches. (+ and – 0,01 Mhz)
5. After all modules work as they should I just put the them all together.
There are some Pictures that showing a “cool” old style cell phone like antenna to make it here is an instruction in an instruction.
1. Get some silver plated cooper wire I just get about 30cm and wrap it around an screwdriver.
2. Cut out piece long enough and with a large enough diameter from your favorite colored heat shrink tube.
3. prepare something I call a “Buchse” and solder it to your board at the antenna connection from your TEA modul.
4. Finished you plastic coved removable antenna.
Step 7: Get some libraries
I try to keep the software small and easy, so I search for libraries I can use, this was also my first try with the arduino IDE.
Here are the links to get the libraries and the documentation
Wire.h -> http://arduino.cc/en/Reference/Wire
TimerOne.h -> http://playground.arduino.cc/Code/Timer1
ClickEncoder.h -> https://github.com/0xPIT/encoder/tree/arduino
ShiftRegister74HC595.h -> http://shiftregister.simsso.de/
TEA5767Radio.h -> http://playground.arduino.cc/Main/TEA5767Radio
Step 8: The sourcecode
There is still a lot to do with the project every help is welcome, special I have no idea in the moment how to use the 4 tactile switches as station memory switches like in those old style radios.
So just download my first try of software here and enjoy something of my “code”
Step 9: Video
Of course at the end of my totally “cool” oldstyle instruction here is my “proof of concept” video so you can see even with messy wiring it work. Hope I won’t get any problems with any copyright because you can hear sometimes some radio stations….