RF link 434 problems


few days ago I received these two RF link modules from Tinkersoup: http://www.tinkersoup.de/product_info.php?products_id=49 http://www.tinkersoup.de/product_info.php?products_id=35

Sparkfun has links to these items as well, together with links to documents on how to set them up.

Nice little items, but when set up on two different arduino's (diecimilla168 & duemillanove328) all my receiver receives is random numbers between 0 and 255! >:(

Problem is that I don't know which setup is at fault: the transmitter or the receiver...I guess I better build a field effect meter first... :)

Did any of you guys got these RF link modules to work? If so: how? On which pins? Code?

BTW: the code and setup I use is the one described in this document: http://www.sparkfun.com/datasheets/RF/KLP_Walkthrough.pdf.

Last note: I don't use antenna's; the two arduino's are connected to the same computer and seperated bij 20 cm...I didn't think I would need an antenna :)

What baud rate have you got set?
The maximum for these devices is 2400.
Do you get reliable results if you lower the baud rate, say to 300?
Do you still receive rubbish if the transmitter is not switched on?

Try the VirtualWire library. I have a pair of those from SparkFun and it took me about 10 minutes to get them wired and communicating.

+1 for VirtualWire suggestion from me. (And I’ve actually used it finally, must get around to uploading the pictures of the mini-shields i made. :slight_smile: )


Tnx guys, will try all your suggestions when I come around to it...probably somewhere today or tomorrow...

Will keep you posted...

One question though (well actually two):

Do you guys connect the two data pins of the receiver? And do you think I should use antenna's, even though both arduino's are so close to each other?

Not to hijack this thread, but I am very interested in the RF link connections. I'm hoping to hook a transmitter up to my PC via either a Serial->MAX232->TTL->RF -->> RF->Arduino setup or a USB->TTL->RF setup. Basically I want the Arduino to be able to be far from the computer but still be able to receive RSS feeds, time of day, etc.

Anyway, has anyone tried that, or does everyone just make Arduino to Arduino connections? If so, what did you use on the computer to send data to the Arduino? Right now I can and do use Processing (I run with a USB cable for now) , but I want something I can minimize to tray or have running in background.


Well...I tried most everything and can't get it to work :( Different (lower) baudrates, antenna's, VirtualWire library.... no luck!

I build myself a simpel field strength meter and do no see any difference wether the transmitter is powered on or off...maybe a broken transmitter after all :(

As for Repthe603: I think you better start a topic of your own...

Right, I'll do that. But for you, I have to ask...can you open the serial monitor in the Arduino IDE on BOTH arduinos while the RF is set up? Assuming you are using USB boards, you should be able to, and that will let you see what is being sent AND received. Otherwise, you may have gotten the shaft and have broken components.


yes I can, but of course I can only see what is being fed to the transmitter module that way...I can't check whether it actually transmits... :-[