|T O P I C R E V I E W
||Posted - 01/30/2013 : 7:14:31 PM
Is it possible to hear insteon RF signals if you're using a UHF radio? What frequency would it be at, 904.000MHz?
|10 L A T E S T R E P L I E S (Newest First)
||Posted - 02/03/2013 : 8:37:33 PM
RCWagner is on the right track in trying to hear Insteon RF activity with a UHF receiver. With a decent 900 Mhz antenna, one of the trouble shooting activities with RF link failures is to try and see how from from a Dual Band switch one can hear that transmission, ot that it exists in the first place. The antenna inside the Insteon switch is short and surrounded by components and the metal electrical box, which would limit range. I used a Rohde & Schwarz FSH3 spectrum analyzer. Until I saw it on the screen, I didn't realize my older RF couplers were on a different frequency than the new Dual Band dimmers. Especially important with the neutral-less RF only dimmers. They need another dual band dimmer or access point within range.
When things are working, I see on the analyzer is a series of transmissions that seem to be the mesh network. The first "longer" transmission is followed by a number of shorter ones. When an RF dimmer isn't responsive, I hear about 4 equally spaced transmissions. My UHF radio receiver is much more sensitive than the wall switch or even spectrum analyzer. This helps troubleshooting the Insteon RF network in the home when a new switch installation seems unresponsive.
||Posted - 02/01/2013 : 08:37:23 AM
I have a RemoteLinc #2440 that I'm using with to turn on/off lights. With my radio on an sitting 3 feet from the RemoteLinc, I hear static, pretty much as if you were listening to a broadcast AM radio tuned between stations. Even if I set the 2440 on top of the radio, i hear the same static. At the same time I have a broadcast radio turned on, listening to static. When I press the one of the keys on the RemoteLinc, the broadcast radio remains unchanged (just static, no change in the s-meter), but the UHF radio bursts out with harsh, loud sounds (S-9 from S-0). It lasts about 1 second in total, then back to white noise. Lights on, lights off, same characteristic. Its quite obviously from the insteon device.
Now if I go to the switch I'm controlling with the RemoteLinc and toggle the lights on/off, I don't hear anything. But that switch is not programmed as a sender, only a receiver, so that's probably not surprising.
As I mentioned earlier, in FM mode I also hear the signal but it comes across as more "musical".
I haven't played with this too much, but I've verified several switch devices will trigger my radio. Only for a short burst right after I toggle a switch. I even have some "missing" devices (lamp modules not in use) programmed for control by a RemoteLinc (or other) and I get the chirp controlling them too, even though they are not present. Definitely not due to the load.
||Posted - 02/01/2013 : 07:16:52 AM
I cannot hear 38kz either
When you say AM mode makes me wonder. Are you switching on any dimmers?
How long do the sounds last? Very brief at turn on/off or any time the load is on?
Any chance you are hearing high freq. emissions created by the dimmers chopping of the A C waveform?
||Posted - 01/31/2013 : 8:30:34 PM
In FM mode I hear nothing. In Wideband FM I hear short bursts that sounds somewhat like an old dot matrix printer.
||Posted - 01/31/2013 : 8:20:53 PM
I have a VHF/UHF Kenwood handheld radio. I put it in AM mode and toggled a few switches around the house. It doesn't sound like 38KHz, because I can't hear anything above about 15-18KHz. It just sounds like intermittent static. There is the "regular" background white noise but when you toggle a device that communicates with another Insteon device, you hear much louder static that starts/stops several times. krccccck krck krccck krck krck
||Posted - 01/31/2013 : 7:10:25 PM
On what radio?
Did it sound like 38,400Hz?
||Posted - 01/31/2013 : 6:33:18 PM
Thanks all. I was able to hear the signal at 915MHz. Of course I can't decode it, but I can tell that devices are sending.
||Posted - 01/31/2013 : 05:49:53 AM
Is it possible to hear insteon RF signals if you're using a UHF radio?
The simple answer is "no".
||Posted - 01/31/2013 : 04:47:53 AM
No 904MHz was the original Insteon RF frequency in th 2442 SignalLinc RF.
It is now 915MHz. For all presently made devices in the USA and Canada. The European ones are on different RF Frequencies.
If you search the FCC Database for the Grantee Code SBP you can see many of the devices and also note some may have a slightly higher or lower frequency listed.
As Stu pointed out. You would have to demodulate it first.
I looked at some of the data one time. By looking at the received data out of an old Access Points Receiver Daughter Card.
Also used a scanner and manually set it to 915MHz. You can hear the short data bursts.
||Posted - 01/30/2013 : 10:52:45 PM
Only if you can sense frequencies beyond the audio spectrum, the limits of which are somewhat above 30,000 Hz. (30 kHz.)
What one actually hears at RF frequencies is the demodulated signal, for example, from amplitude modulation (AM) and frequency modulation (FM) radio waves. A similar technique is use to transmit video. The radio wave is the carrier of the audio or video signal, not the part that's heard or seen.
There are devices, such as an oscilliscope, that will allow you to observe a mathematical representation of the signal visually.