The devices can be fussy at times. One of the things that they do NOT like is to bee in close proximity to a GPS device -- as your friend if this was the case. There is something about the competing signals in the close environment that causes the SPOT to cancel out. I have known a few people who could not figure out why their SPOT would be so troublesome, and when I mentioned the GPS issue (does not happen all of the time, BUT, I would consider it counter productive to place the device in a compromising situation) It works fine if one person carries the SPOT and another carries the GPS. I am not sure how far apart the devices should bee, but I err to the side of safe on this one. When I hike alone, I don't carry a GPS because I am very familiar with the terrain AND I have a map, too.
B
