Not Receiving Anything at all

315MHz and 433MHz wireless connections are very commonly used by consumer electronics including weather stations, home automation remote controls, power consumption meters, car alarms, and also many DIY projects.
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epinc
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Not Receiving Anything at all

Post by epinc » Fri Sep 20, 2013 6:29 pm

Just got several of these Receiver shields at 433MHZ. I also ordered various 433MHZ transmitting devices including a weather station, pool temp monitor, keychain, and garage door transmitter. All of them indicate they are at 433MHZ

But no matter what arduino script I try, I do not get any outptut at all from the device.

I am watching pin 8. I've tried the sample code from Practical Arduino, I've also tried a simple script that fires a pin interrupt when pin 8 changes and nothing happens (script I found on another post here in the forum). I've also tried the Virtual Wire library as well.

When I used the pin interrupt script nothing happens with the receiver, but if I put a jumper wire into the pin socket and move it in and out quickly I can see some output so I know the code is working.

I have 3 of these boards. The chance that all 3 are bad are slim, leaving me to believe I must be doing something really really silly that is causing me not to receive any data.

I've been working wtih Arduino for quite some time, and have interfaced Arduino with both Wifiy and Bluetooth chips, so I do have a bit of experience with it, but this board is driving me crazy as even with 4 different 433MHZ devices transmitting right next to it I am not seeing anything going onto pin 8

angusgr
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Re: Not Receiving Anything at all

Post by angusgr » Sun Sep 22, 2013 11:55 pm

Hi epinc,

That's very odd indeed! Sorry to hear nothing is talking.

Only one possibilty I can think of, which is a bit remote as well, is that all four of the devices you have are transmitting 433MHz FSK (Frequency Shift Keying) rather than ASK (Amplitude Shift Keying) aka OOK (On-Off Keying) which is the modulation scheme that the receiver shield supports.

This seems unlikely though, especially for things like cheap 433MHz remote controls which are usually ASK. Also I'd expect FSK might also cause some garbage output to be seen from an ASK receiver.

Can you give any more details about the 433Mhz transmitters you have? Chip names would be particularly useful if you can get at the internals of any of them!

(And just to be sure, the RXB6 receiver modules on the shields you have are definitely marked 433MHz, we haven't accidentally sent you 315MHz ones?)

Regards,


Angus

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jonoxer
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Re: Not Receiving Anything at all

Post by jonoxer » Mon Sep 23, 2013 1:09 am

The VirtualWire library is a great way to test these receivers, but you also need a matching transmitter. VirtualWire implements its own comms protocol, so you can't just run the VW receiver and see data coming from random devices. You need a VW transmitter at the other end as well.

I've used VW many times with a pair of Arduinos, one with the 433MHz receiver shield and the other using a 433MHz ASK transmitter module like this one connected to another Arduino:

http://www.jaycar.com.au/productView.asp?ID=ZW3100
--
Jon

epinc
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Re: Not Receiving Anything at all

Post by epinc » Mon Sep 23, 2013 3:17 pm

Hi!. Thanks so much for the reply! My fear is that there is something very simple that I am missing that is causing this issue but I've had a few other people try and we are all having no luck with this so far.

The 4 devices we have so far are:

a) A remote we manufacture ourselves operating at 433.9 MHz. The tech document for it says that is uses "pulse width modulation, On/Off keying"

b) A La Crosse Technology WS-9029U Wireless Weather Station

c) A SVP Professional Wireless Pool Thermometer Series operating at 433 MHZ

d) An ALEKO Remote Control for Gate Opener Remote Transmitter 433MHz

We really want to get this working with the remote we currently manufacture for our customers. I bought the other 3 devices from amazon just to have some extra transmitters to rule out an incompatibility with our transmitter.

The boards are marked as "433MHZ". I've ordered in a few 315MHZ transmitter though to make sure that isn't an error.

I bought the boards from epic tinker since they could ship faster. I have also just ordered several boards directly from your site to see if perhaps they work better.
angusgr wrote:Hi epinc,

That's very odd indeed! Sorry to hear nothing is talking.

Only one possibilty I can think of, which is a bit remote as well, is that all four of the devices you have are transmitting 433MHz FSK (Frequency Shift Keying) rather than ASK (Amplitude Shift Keying) aka OOK (On-Off Keying) which is the modulation scheme that the receiver shield supports.

This seems unlikely though, especially for things like cheap 433MHz remote controls which are usually ASK. Also I'd expect FSK might also cause some garbage output to be seen from an ASK receiver.

Can you give any more details about the 433Mhz transmitters you have? Chip names would be particularly useful if you can get at the internals of any of them!

(And just to be sure, the RXB6 receiver modules on the shields you have are definitely marked 433MHz, we haven't accidentally sent you 315MHz ones?)

Regards,


Angus

angusgr
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Re: Not Receiving Anything at all

Post by angusgr » Mon Sep 23, 2013 10:30 pm

Hi epinc,

Very unusual. It sounds like you have some good avenues to follow up, please let us know how you get on with these (or if there's anything else we can tell you about the receivers.)

- Angus

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