At the push of a button, it sent an e-mail message to friends and co-workers reporting that I was OK and just checking in. The message arrived complete with the latitude and longitude of my position when sent.
And there was more - a Web link to the aerial photographs of Google Maps.
The link opened to a broad aerial photo of the valley, but a viewer could zoom it in to a football field-size chunk of terrain or smaller. In later looking at photos of the finest scale, it was obvious that if Spot hadn't positioned me under the exact tree, it was within a couple feet of it.
Spot - www.findmespot .com - bills itself as the ''The World's First Satellite Messenger.''
Only slightly bigger than a hockey puck and about the same weight, the device is part personal locator beacon and part communicator.
Push the ''911'' button and Spot calls for the cavalry just like any other PLB. But there are other options with this device.
Your personal computer can be used to program E-mail messages into both ''Help'' and ''OK'' buttons on Spot. You can then send these messages to anyone who can connect to the Internet - be it by home computer, wireless laptop or cell phone.
Kirk Garoutte of Susitna Energy Systems here in Anchorage is promoting Spot as a low-cost alternative to the satellite phone for wilderness communication and safety. Spot retails for about $170 with an annual fee of $99.99 to provide tracking services.
Even at package cost of approximately $270, this is a fraction of the $1,300 to $1,400 cost of a satellite phone, not to mention the exorbitant costs of satellite air time.
That's the big upside of Spot.
The downside is that unlike with a satellite phone, there is no ready way to tell whether Spot is actually communi- cating.
When you make a phone call, the person on the other end of the transmission provides a comforting verbal acknowledgment. With Spot, you have to put a lot of faith in technology.
Technology, unfortunately, is prone to both hardware and human glitches.
Garroute was good enough to loan me a Spot to test for a couple of weeks. The first problem I encountered was the human glitch.
Spot was duly programmed with ''help'' and ''OK'' messages.
I took it out into Chugach park, pushed the ''on'' button, saw the red light that indicates the unit is on, and pushed the ''help'' button to send messages to friends and co-workers saying ''Help, Craig can't come to work today.''
A red light went on to indicate the message was being sent.
Nobody, however, got any e-mail.
I thought maybe there had been found a valley deep enough to block satellite communications.
Spot warns on its Web site that Southcentral Alaska is in a zone with only 96 to 99 percent ''probability of successfully sending a single message within 20 minutes.''
I decided to give Spot another try in the big park behind Anchorage.
This time Spot made a connection and sent the e-mails, but provided no indication of the location from which the message had been sent.
Curious about that, I went back and carefully reread the instructions on operating Spot. This time a careful note was made of that warning about sending a message ''within 20 minutes.''
The third time Spot was tested, it was put under the aforementioned Potter Valley tree and left on for 20 minutes.
It immediately became obvious Spot could have some strong, practical implications in Alaska.
If, for instance, you were out snowmachining somewhere in the Susitna Valley and had set up camp where you wanted friends to meet you for the weekend, you could send a message saying ''Meet me here.''
Or, you could simply carry Spot around to be able to inform loved ones that ''We're late, but we're fine.'' They could then go to Google Maps to see exactly where it is that you are stuck.
