This might be a stretch but here is something I had going on that took me
awhile to figure out
I had one of these driveway sensors that uses an Infrared motion detector
and sends a rf signal to a 'beeper' in my basement room when ever someone
approaches the house. It sorta quit working at some point in time as it
would beep me and no one would be at the front door.
Around the same time all of my remote temperature sensors quit working. I
put new batteries in the wireless temperature sensors but that did not
change things. I finally tuned around the UHF band and here was this signal
that was really strong and hard to tune in. After a bit of T-Hunting, I
determined it was the driveway sensor. I pulled the battery and then
noticed my temperature sensors were back on the air. As I recall, the
driveway sensor was not on the same frequency the temperature sensors were
but when it failed, it put out such a signal that it was suddenly very broad
and apparently that was enough to do in the remote temp sensor receivers.
It turns out the unit had a hard failure and anytime batteries were put in
it, it was transmitting.
Some similar transmitter could have gone wacky at your place, or possible
just a low battery is causing it to somehow really smear it's spectrum.
That coupled with the inherently broad band receivers they use in all of
these little receivers could be your problem.
First thing to do would be to see if you have some remote transmitter that
is not working right, either not working at all, or seems intermittent. If
so, change the batteries and see what happens. It's a little hard to
diagnose your problem since it is so intermittent, but this is something
that could typically be found around your house and you don't think much
Again, just a data point. Your mileage may vary!!
RFI mailing list