Meet the RFXCOM RFXtrx433E


RFXCOM RFXtrx433EHere’s the newest addition to my ever-growing list of hardware that make my HA system to what it is: the RFXCOM RFXtrx433E USB 433.92MHz Transceiver. The grey enclosure measures 82 x 58 x 22 mm which is really small, compared to the other RFXCOM transmitters and receivers I bought back in 2007. But size doesn’t matter at all in this case – the list of supported actors and sensors seams to have exploded in the last 7 years! The same goes for the number of Home Automation Systems that support the RFXCOM products. And if the Home Automation system you use is not listed, there’s an Open Source SDK to make your own plugin/driver for RFXCOM.

RFXCOM RFXtrx433EThe RFXCOM has a USB-B connector and 2 LEDs: the left (red) one is lit while the RFXtrx is booting while the other (yellow) one will light up when the RFXtrx has received an RF transmission it could decode.

Along with the hardware comes a range of documentation and software to test, configure and use the RFXCOM products; RFXMngr is probably the most important one for most – look here for a complete list of all the available downloads.

So let’s connect this small yet very powerful transceiver to one of my SBCs and see how it works.

Since I’m into Node.JS since a year or so, the first thing I did after unpacking the transceiver was searching for a NodeJS module for it and I found this one, made by Kevin McDermott. Well, life just can’t get easier than this; install the module and a script of <100 lines of code will suffice to receive all your sensors!

RFXCOM TH sampleHere you see the information from a received RF packet, transmitted by one of my Oregon Scientific Temperature/Humidity sensors – all stored in a convenient JSON object and ready for further processing. What more can you wish for? It just doesn’t get better than this 🙂


Well… there is a special reason why this new RFXtrx433E is very interesting in my case; that’s because this RFXtrx433E supports the Somfy RTS protocol. That would mean I can combine an old RFXLAN receiver, an old RFXLAN transmitter and my expensive Somfy RTS485 transmitter in a single product! That would be really nice.

But for that, the reliability of the Somfy RTS protocol is crucial, so I focused on that during my first hours working with the RFXtrx433E. Today I ‘paired’ our 12 Somfy roller shutters with the RFXtrx433E so that I could use it to control those roller shutters with it. I sent a ‘PROG’ command to the Somfy RTS485 transmitter, followed by a RFXCOM RFY ‘program’ command after the roller shutter responded to the ‘PROG’ command by 2 small movements.

      case 'up':
      case 'down':
      case 'stop':
      case 'program':
        console.log('Command unknown: '+command);

After that I tested whether the roller shutters obeyed the ‘up’ and ‘down’ commands sent by the RFXtrx433E and 2 hours later I was done programming all 12 roller shutters. Now I can use my new RFXtrx433E as a remote for all of ’em – what’s left to do is ’embed’ the RFXtrx433E in my HA system and see what happens during the next couple of weeks.

Exciting, although I think I already know what the result will be – cause RFXCOM products have never let me down before!

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19 Responses to Meet the RFXCOM RFXtrx433E

  1. jules says:

    Hi I just saw this article – I am running an Openremote HA system on a Windows XP machine. I have node.js already running which interfaces to Sonos nicely.
    The only issue I see is that my HA server is quite a long way from my somfy rts shutters. What sort of range have you managed? Alternatively do you think I could put the RTx on a raspberry pi which is in range then somehow connect to that?

    • Jules,
      The range of the RFXtrx433E is very good. Actually, the location of my RFXtrx is the worst possible in my case, all the way to the back of the house, ground floor. And it *never* misses, even with roller shutters at the other (front) end of the house at the 1st floor (with lots of concrete & brick walls in between, at least 16 meter distance). And even if that wouldn’t suffice in your case you could always use a nearby RPi for better positioning of the RFXtrx – mine is connected to a Cubietruck USB port, so there’s no real difference with using a RPi 😉

      • Martin says:

        I have a RFXtrx433 connected to a Raspberry Pi to control LightWaveRF devices around the home. I use node.js running the NodeRed framework. My set up hangs on a wall so swapped the RFXtrx433 antenna to one with a 90 angle (cheap on ebay). Reception is much better than the original antenna pointing horizontally. It might be worth experimenting with alternative antennas.

  2. jules says:

    Thanks Robert sounds pretty similar set up to mine with concrete walls so will give it a try. Certainly much cheaper solution to others I’ve found.

    Have you got any Velux IO-homecontrol windows/blinds? That is my final challenge…

    • No, I don’t have any Velux IO-homecontrol windows/blinds so can’t help you with that.

    • Geert says:

      Hi jules,

      Same challenge here. I have ordered the Velux IO-homecontrol windows and will have them installed in the next couple of months. As far as I understand, it could be a hard time to get them controlled via your own HA due to the closed system design of IO-homecontrol. Let me know if you find anything 😉

  3. Victor says:

    I also bought the RFXCOM RFXtrx433E and attached it to my Synology NAS with Domticz on it. I programmed the Somfy RTS and all the blinds are working correct BUT I also have shutters with Somfy RTS but they dont work correct. You change the postition of the shutters (to let more sunlight in for example) and the controls (in Domoticz) are wrong. If you click the blinds up icon it tries to close the shutter (let less sunlight in). If I press the STOP button from within Domoticz the shutters go down but there is nu button to go down.

    Do you also have those shutters or only the blinds? Maybe I have to look at the RFXmngr to see what is send or do you have any advice?

    • Hi Victor,

      I only have roller shutters (rolluiken), no blinds. All 12 roller shutters are working just fine, they’re behaving like they should 😉
      0x00 = stop, 0x01 = up, 0x03 = down.

  4. Chris says:

    I believe my last comment got lost, so here it is again:

    Great project! Any chance you can share the code for the node.js somfy controller. I’m having a hard time getting the node-rfxcom to work.

    • Hi Chris,

      I’m in the process of contacting the person that made the nodeJS module to which I added Somfy support but no luck so far.
      If this takes to long I’ll put my code on Github; just remind me to do so in let’s say 2 weeks 😉

  5. Branislav says:

    Hi Robert,
    I would like to see the code as well as I have no luck with the integration of my Somfy blinds with rfxtrx433e using the node-rfxcom. Could you please post your code to Github, or elsewhere, so we can see what you have done? It would save us a lot of time and we would really appreciate that!

    Great job btw! I ordered this device based on your blog, and it has been perfect so far (e.g. integration with weather sensors was very easy :-).

    Thanks a lot and keep blogging please 🙂


    • Hi Branislav,
      Thanks and I know it has been quiet for a while, but posts will keep on coming whenever I have some time 🙂
      I’ve had contact with the person that made the original NodeJS module for the RFXtrx and which I extended with Somfy (RFY) support. As soon as I have the time I’ll do a push request to get my code in there – I’ll let you know (by a comment on this post) when that has happened. Time … 🙁

  6. Lukasz Piech says:

    Hi do you know if this RFXtrx433E works with shutter remotes like this one? and do you have some documentation how to use RFX in Fibaro HC2? I was thinking about using something in HC2 to control shutters but retain the original remote as well

    • Hi Lukasz,
      I don’t know those shutter remotes so I can’t answer your question about those. If you own a RFXCOM receiver, why not ask
      The combination of HC2 and RFXtrx433E isn’t one I’ve ever seen – maybe you got the impression that I’m using the RFXtrx433E with the HC2 because I’ve posted about both, but I don’t. I have the HC2 for other purposes then my own HA system. So I can’t help you on that either…

  7. Ben says:

    Interesting article. What I am wondering about: would it be possible to ‘capture’ an RF command (from cheap 433mhz home domotics kits), and rebroadcast it whenever you want? If not; anyone knows this would be possible with another device?

  8. Martijn says:

    Hello Robert,

    Really nice post. I’m trying to get the RFXtrx433E to work with nodejs. Till now no luck. Would be much appreciated if you can publish your code.

    Best regards,

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