Comments on: Jonathan’s WildSnow Beacon Test Notes

By: Jonathan Shefftz

Jonathan Shefftz — Mon, 04 Jan 2010 03:48:40 +0000

I recently ran some add’l RFI tests, with some interesting results, both concerning new devices and new beacons (or rather, combinations I hadn’t previously tested of new devices + old beacons).

First, previously I had found that a CDMA (Verizon) basic phone (i.e., makes phone calls and does nothing else) does not cause interference when on yet not transmitting, and does cause interference when transmitting. However, this time I happened to notice that the phone briefly causes interference when being flipped open, even when not making a call.

Second, previously I had been unable to detect any interference from a Garmin 60Cx GPS unit. This time though I tried the GPS when some old M2 and F1 beacons (which are generally not the subject of my various tests). When held very closely, the GPS caused interference.

Third, a tried a Spot satellite messenger, second generation. When on, but not attempting to send a message, no interference. When transmitting a message, caused interference in some beacons.

Overall, my conclusions from all this are that:
- RFI issues can be very specific to certain beacon + device combinations; and,
- RFI is often not caused by transmission but rather by power issues.

By: Andy_L

Andy_L — Wed, 15 Jul 2009 16:29:40 +0000

Lou & Jonathan,

The interference info is critical stuff! Linked over to you, and I’ll try to remember to bring it up again when winter’s here.

By: Mark

Mark — Wed, 15 Jul 2009 14:43:49 +0000

Testing for interference with things like iPhones, iPods, cell phones, and the like is certainly smart. It is a little frightening to note how some of these devices foul up beacons’ functions.

By: Kevin

Kevin — Wed, 15 Jul 2009 00:13:35 +0000

In your write up I did not see a test of the iphone Avi beacon application that Wildsnow reviewed on April 1st :)

On a serious note I must say the mere thought of having a cell phone on while in the back country is troubling. But when I come down Vail pass and see all of the tracks on one of the more deadly exposures in this country it becomes more believable that folks would leave their phones on knowing they have coverage in this area.