Arduino Forum

Using Arduino => General Electronics => Topic started by: fasterthanlight on Feb 15, 2013, 11:22 am

Title: 433mhz Receiver
Post by: fasterthanlight on Feb 15, 2013, 11:22 am
Due to conflicting information, there is a good chance i connected one of these up wrong, switching Gnd and 5v. Now i can't seem to get it to work.

Does that mean its fried? And is there a way to test this?

Thanks.

FTL

(http://circuit-zone.com/ediy_blog/56/433MHZ_RF_RECEIVER.jpg)
Title: Re: 433mhz Receiver
Post by: Krodal on Feb 15, 2013, 11:53 am
The only way is to buy an other one to compare them.

Was it powered via the Arduino with the USB bus or did you use an adapter with more current ?
Title: Re: 433mhz Receiver
Post by: fasterthanlight on Feb 15, 2013, 11:58 am
Via the arduino.

Title: Re: 433mhz Receiver
Post by: Riva on Feb 15, 2013, 12:35 pm

Due to conflicting information, there is a good chance i connected one of these up wrong, switching Gnd and 5v. Now i can't seem to get it to work.

Did you ever have it working? Assuming you have a matching transmitter then try the below sketch to see what you get.
Code: [Select]
void setup() {
   pinMode(3,INPUT);        // ISR 1 Pin
   pinMode(7,OUTPUT);       // TX Pin
   pinMode(13,OUTPUT);      // Onboard LED
   attachInterrupt(1,rxISR,CHANGE);
}

void rxISR(){
   digitalWrite(13,digitalRead(3));    // Echo pin state to LED
}

void loop() {
   digitalWrite(7,HIGH);
   delay(100);
   digitalWrite(7,LOW);
   delay(100);
}

EDIT: Adding explanation...
Connect arduino pin 7 to the TX module DATA pin.
Connect arduino pin 3 to the RX module DATA pin.
Connect arduino 5V & GND to VCC & GND respectfully on both modules.
Upload sketch and run it and the arduinos on-board LED (pin 13) should flash on/off as the transmitter is turns on/off.
Title: Re: 433mhz Receiver
Post by: fasterthanlight on Feb 15, 2013, 01:31 pm
Right, got the receiver working. Thanks for the help folks.

Now to figure out the transmitter. I can't believe it cam with no documentation. All these devices are different.

How can i tell what pins are what. Will photo be useful?

FTL
Title: Re: 433mhz Receiver
Post by: Riva on Feb 15, 2013, 01:54 pm

Now to figure out the transmitter. I can't believe it cam with no documentation. All these devices are different.

How can i tell what pins are what. Will photo be useful?

Look on both sides of the board near the pins and hopefully it will have something. If not then send pictures of both sides of the transmitter. The example image I posted has 3x TX module pins that are DATA, VCC & GND as you look in the photo but yours may be different so best to be sure first.
Title: Re: 433mhz Receiver
Post by: fasterthanlight on Feb 15, 2013, 02:35 pm
Hope these are clare enough.

FTL
Title: Re: 433mhz Receiver
Post by: Krodal on Feb 15, 2013, 02:54 pm
I can't find it.
The pins are most of the times : Ground, Data, Vcc, Antenna.
If you look at the board with a magnifier, perhaps you can see which pin is ground and which is the antenna.
Title: Re: 433mhz Receiver
Post by: fasterthanlight on Feb 15, 2013, 03:05 pm
Its difficult to tell what is what. Even with a magnifyng glass... the back is really cluttered.

FTL
Title: Re: 433mhz Receiver
Post by: Krodal on Feb 15, 2013, 03:12 pm
Do you have a flat bed scanner, perhaps that can make a good scan/photo.
Title: Re: 433mhz Receiver
Post by: Learning on Feb 15, 2013, 03:14 pm
Put your camera on manual focus, and back away from the paper it's on. The background paper in the foil side shot is in focus, but with the limited depth of field, the foil side is out of focus. Manually focus that camera if you can, else take multiple shots of both sides, and pick those two that are sharp. Keep it smaller in size, we can blow up a clear shot on this end.
Title: Re: 433mhz Receiver
Post by: Riva on Feb 15, 2013, 03:16 pm
Looks like they forgot to silkscreen  the board  :(
The image of the back (with components on) could be a bit clearer.
Looking at the front (the side with the big metal can) the second pin (from the left) is most likely GND but without a clear picture of the back cannot figure the other pins out.
Wait for other peoples opinions and hopefully grab a better image of the back but my guess is ANT, GND, DATA & VCC or ANT, GND, VCC & DATA
Title: Re: 433mhz Receiver
Post by: fasterthanlight on Feb 15, 2013, 03:35 pm
This is better.

FTL
Title: Re: 433mhz Receiver
Post by: Erni on Feb 15, 2013, 03:51 pm
It Looks like this one

http://detail.china.alibaba.com/offer/1126300215.html

But as you say there are so many different.
Title: Re: 433mhz Receiver
Post by: fasterthanlight on Feb 15, 2013, 04:01 pm

It Looks like this one

http://detail.china.alibaba.com/offer/1126300215.html

But as you say there are so many different.



Close bit no cigar...

FTL
Title: Re: 433mhz Receiver
Post by: fasterthanlight on Feb 15, 2013, 04:09 pm
Two flatbed scans. Hope this helps.

FTL
Title: Re: 433mhz Receiver
Post by: Riva on Feb 16, 2013, 08:42 am
This is still a guess as it's not certain where all the traces go but looking from the back (component side NOT can side) I think it's VCC, DATA, GND & ANT
Title: Re: 433mhz Receiver
Post by: fasterthanlight on Feb 16, 2013, 10:34 am
Thanks alot for the help everyone. Esp Riva, I'll have a go at you suggestion, if it doesn't work i guess a new one WITH the silkscreen is whats needed.

FTL