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Have you hit Google with "oregon scientific rain gauge protocol" - there seems to be some information, though whether it applies to yours I don't know. The JeeLabs link looks useful.

Hello,

I tried myself to listen to Oregon THN132 and THGR1222NX on the 3 channels and the EmonCMS doesn't received anything.
 

Even on the RAW data received on /var/log/rfm12piphp.log on a raspberry.

I think maybe it's because of the JeeLIB's method rf12_recvDone in the RF12.cpp file, it seems to wait for a NodeID which is maybe not the protocol of Oregon.

I think it might be possible to hack something to get the Emon to be able to understand Oregon devices, because of this URL : http://jeelabs.net/pub/docs/jeelib/classOregonDecoder.html#ad5b0e557b920c845654683b63b6e815d

After few experiments, and listening to raw data from rf12_recvDone() i was not able to receive any packet from any Oregon device.

Is there any lack of hardware, which prevent the RF12 from an EmonGLCD of listening another 433Mhz message from Oregon Scientific devices ?

oregon stations (and others) use a different method for transmitting data albeit using the same frequencies... See here: http://jeelabs.net/projects/cafe/wiki/Receiving_OOKASK_with_a_modified_R...

In short ... The rfm12b should in theory be able to be reprogrammed to listen for ook messages, but range will be abysmal, and you'll probably be unable to receive both kind of transmissions (emontx-fsk and oregon-ook) using one unit without losing a lot of them

You'll be much better off connecting an rfm01 module to a raspberry (can be done in parallel to the rfm12pi module) and use that to receive the sensors data using the appropriate software

Thank you for this explanation, i'm new to RF, then i read this paper :

http://cirronetinc.com/products/apnotes/ookvsfsk.pdf

And the conclusion at the end of the document is :

CONCLUSION
The following points have been made in this paper:
1. OOK transmitters are simpler than FSK;
2. OOK transmitter current is 50% lower than FSK;
3. SAW based OOK transmitters are more robust when exposed to extreme temperatures, vibration and shock;
4. FSK transmission requires 1.5 times the bandwidth compared to OOK;
5. OOK receivers are simpler than FSK;
6. OOK receiver sensitivity is equal to or better than FSK;
7. Properly implemented, OOK receiver performance in the presence of co-channel interference is generally better than FSK;
8. Properly implemented, OOK receiver performance with amplitude flutter is equal to or better than FSK.

I wonder why openenergy monitor chose FSK ?

Well, because it is the protocol the rfm series of transceivers was designed for, and because of the possibility of transmitting a lot of data (compared to ook anyway) in a shorter period of time ... I think both protocols suit a different need ...

OK, Thank you.

I'm pretty happy to be sure that Oregon's devices cannot annoy my electric monitoring.

Do you think it can be a good idea to unsolder the RFM12 chip, and solder a RFM01 ( like http://uk.farnell.com/quasar/rfm01-433-s1/rf-mod-receiver-fsk-433mhz-smd/dp/1878272 ) instead on a daughter RFM12Pi V2 board ?

The processor, and the daughter format of this board is very convenient for raspberry...

Hi, according to info posted on this page:

http://www.susa.net/wordpress/2012/08/raspberry-pi-reading-wh1081-weathe...

the pinout of the two modules is the same, but the SPI registers and control functions are different so I 'think' you would need to adapt the rfm12b firmware to ralk with the rfm01 instead

I am using an RFM01 module in parallel with the rfm12b, I followed the wiring described in the pinout attached, and had only to break out 3.3v and ground from the rfm12b module, all the other pins are unused from the RFM12b. The downside of connecting the rfm01 directly is that you have to find a software that will operate it to receive data from oregon sensors (the software described in the link is for WH1080 weather stations)

Yes i already saw this page... i think it's the only one on the internet useful :-D

But if you are using both RFM12 and RFM01, you have two different serial tty available ? ttyAMA0 and ttyAMA1 ?

I will try this, having both on the same raspberry is saving some more watts :-)

Thank you.

I think it is more correct to say two devices,  the rfm12b module talks over serial with the standard rfm12pi daemon receiving fsk transmissions data from two emontx modules, and the  rfm01 module is connected directly using the spi ports, receiving ook data from sensors from a wh1080 station (temp,humidity,wind,rain) .... No problem whatsoever handling both and a local copy of emoncms