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Hello all

I've been running an RFXCOM receiver since February 2009. The idea is primarily to receive from an RFXMeter with 3 x RFXPulse counting flashes on the LEDs on 3 electricity meters. Also hope to receive from an OWL/Electrisave, and 3 x Oregon THR128 temperature sensors, and I also have an RFXSensor but haven't set it up yet.

All worked perfectly for about 6 weeks (xpl-perl running on a Linksys NSLU2 'Slug') producing rrdtool graphs of various things. See http://www.viridis.net/rrd/combined.html for the house electricity use (and solar panel generation, scroll down back to when it was working). Also http://www.viridis.net/rrd/ for graphs of the raw data. I'd be delighted to talk more about the setup, but for now, my problem...

At the end of March 2009, without changing anything, the receiver stopped receiving anything (gaps in the graphs). Sometimes it would start working (again without me doing anything). At other times, I'd switch everything off and turn on just the receiver and one transmitter (usually the RFXMeter). Sometimes this would get things going again - it might work for just a short while, or up to a week, but eventually would stop again.

The receiver would either pick up most of my transmitters, or none of them - it wasn't just some devices which disappeared. I've tried most things I can think of: e.g.<ul><li>Turn off xpl-perl and just use RFReceiver on PC for testing. When things aren't working, RFReceiver shows no messages, but can successfully change settings and request the version number (29). I've done the obvious - set variable length, and enable all RF. Again, sometimes it works fine.</li>
<li>Remove the batteries from all 3 Oregon THR128, to rule out one of them causing a problem.</li>
<li>Just experimenting while writing this. Turned on receiver; connected RFReceiver program. Received RFXMeter and Electrisave (and also briefly put battery in RFXSensor, and received from it OK). But after 3 minutes, no more messages from anything. Turning receiver off then on, and reconnecting RFReceiver didn't help - still nothing.</li>
</ul>So basically, haven't managed to correlate the failures with anything. Any more ideas? Otherwise will have to try returning the receiver - wouldn't be surprised if it's found to be working.

A few weeks ago, Bert suggested returning the receiver for testing, but inevitably it worked for nearly a week just after this.

Editing post the next morning:
<ul><li>Just turned on receiver and connected RFReceiver: worked perfectly (receiving RFXMeter and RFXSensor, the only known transmitters turned on) for around 3 minutes, then nothing. I begin to feel that it's more likely to work, even if only for a short while, if it's been turned off for quite a while (e.g. hours).
</li></ul>

Did you buy any new electronics equipment since the moment you started having problems with reception?

A few weeks ago I noticed my RFX receiver also did not receive anything anymore. I have 10 THGR228N sensors located througout the house, a BWR102 scale and some other stuff (motion sensors, remotes), but no data was being received at all.

Using my hamradio equipment I found a continuous carrier on 433.920 MHz blocking all reception.

The BWR102 turned out to be the culprit. Its transmitter was being keyed continuously, thereby blocking reception. A reset and new batteries solved the problem.

Should you have a receiver capable of receiving between 432 and 435 MHZ, place it near the RFXCOM receiver and scan for any continuous carrier near 433.920 MHz. When found, with the antenna unscrewed, try locating the source where the carrier originates.

Looking at the above, I assume the RX problems are RF related. Should you not find any RF related problems, returning the receiver to RFXCOM might be the best option.

Thanks for the reply, Jfn.

No - I don't remember getting any new equipment which might be transmitting and causing the problem. I did several more experiments, never receiving messages for more than a few minutes, then this morning, I turned on the RFXCOM receiver, and it's working - for 90 minutes so far (see the graphs linked in my original post) - I've just got the RFXMeter and the Electrisave turned on. How long will it work for this time?

I'm hoping to borrow something capable of picking up 433MHz to see whether there is interference when it doesn't work.

At risk of getting off the subject, there is another 433MHz device in my house, and what's more it's from the Netherlands (Leiderdorp Instruments LI-12)! It's not new - I've had it for over a year, displaying the output from the solar PV panels. See http://www.leiderdorpinstruments.nl/Ned ... /LI-12.htm (Dutch) or http://www.leiderdorpinstruments.nl/Int ... index.html (English). The manual (download page) says that transmission is two-way. Two 'channels' are mentioned: 433.92MHz and 434.33MHz, but no description of how to select which is used. There is an 'unused' DIP switch (5) - dutch manual for the measuring unit says that this must be set the same on both units, so perhaps this sets the channel? (thanks Google Translate - I can't read dutch!) The RFXCOM doesn't respond to this device, but next time I'm experimenting, I must try turning off both halves of this device (I've previously turned off the measuring unit, but hadn't realised that the display might transmit as well). Still - it's turned on at the moment, and the RFXCOM is working fine.

Well, the RFXCOM has been working fine for 5 days now, as you can see at http://www.viridis.net/rrd/combined.html and http://www.viridis.net/rrd/. It's worked OK for more than 5 days before, so can't yet say if the problem is solved.

5 days ago, experimenting yet again, with just the RFXMeter (3 x RFXPulse) and the Electrisave/OWL transmitting. I noticed that I was receiving the Electrisave OK (with RFReceiver program), but for the RFXMeter, which I think sends the reading from its 3 installed devices 5 times each, I was often receiving just the first part of the group of 15 messages. So maybe some readings from the first RFXPulse, but nothing from the other two.

As described in this forum /topic.asp?TOPIC_ID=2218, I added a 34.5cm piece of wire in the meter cupboard, as a "passive repeater" - I then received all messages from the RFXMeter. It seemed consistent - if I took the piece of wire away, then it went back to missing many messages.

So will it stay working? I can't really see how this would explain that I sometimes didn't receive from any devices for many days.

Encouraged by this, I put the batteries back in the 3 x Oregon THR128 temperature sensors. So far, they've worked as well as they ever did. Mainly OK, but there seem to be some bands of temperature for some sensors which are never received. e.g. http://www.viridis.net/rrd/outside.1/temp/ never seems to work between 16 and 20C.