Howdy all,
I haven't posted for ages but I felt this information would be handy to some people.
I've been working for a manufacturer of garage door and commercial door openers for awhile now and we have found some interesting issues with wireless devices.
This all stems from people who say they have issues with their garage door not working. Our Field Service Technicians will attend site and check for RF issues on the same 433.92 Mhz frequency as the garage door. More often than not we find its actually the home owner has caused the interference themselves (or a neighbour).
The things we find that are most common to cause issues are:
1) baby monitors. Same frequency with a decent range blocks out the signal from a remote control.
2) remote control ceiling fans. Same frequency and when faulty constantly sends out a signal which will stop all 433.92 transmissions including some cars. This is an evil device as the range can extend a couple of houses. Easiest to identify when people can't lock or unlock their car.
3) Wireless doorbells. Same frequency and will block out a signal from a remote. When the transmitter battery starts to die, the receiver starts transmitting a high powered signal looking for the transmitter.
4) Wireless weather stations: same as above only for a greater range.
Now for the big one.
5) AV senders. These are the devices people buy to send an AV signal from the source unit to another TV wirelessly over the 2.4Ghz or 5.8Ghz range. These devices also send the remote control signals, but on the 433.92 Mhz range. The big problem with these units are the range and the signal strength. We have seen these units block out a 5 house radius. No one can operate their garage door, unlock their car, doorbells stop working, baby monitors stop working.
I've set a few units up (i don't want to name brands in case I defame someone) and we have tested the signal strength. for some of the units, we can't reduce the sensitivity of our meters enough to acurately track the signal under 100m from the source.