Figure 12: SPOT's Four Buttons

SPOT has four buttons located on the front of the device:

• HELP - Press and hold the HELP button for 2 seconds to send the pre-configured help alert (shown above in 10). The device will send a help message every 5 minutes for 1 hour, or until the alert is cancelled. To cancel the HELP alert, press and hold the HELP button for 3 seconds.
• ON/OFF - Press the ON/OFF button to turn the device on. Press and hold the button for 3 seconds to turn SPOT off. When the unit is on, the LED above the ON/OFF button will blink once every 3 seconds.
• OK - Use this button to send "I'm okay, just checking-in" type messages to whomever you've setup to receive the OK messages. When pressed, your configured recipients receive a notification containing the message you've configured on SPOT's website and a Google Maps link showing your current position. If you've signed up for the additional "Unlimited SPOTcasting" service, pressing and holding the OK button for at least 5 seconds updates SPOT's website with your position once every 10 minutes for 24 hours. Anyone you've given access to check on you can then login and see where you've been as well as your current location. Pressing the OK button again for 3 seconds turns off SPOTcasting mode. Note that SPOTcasting is automatically disabled if you press either the 911 or HELP buttons.
• 911 - Press and hold the 911 button for at least 2 seconds to send the distress signal to emergency services. The unit will continue sending position information to emergency responders every 5 minutes until the alert is cancelled (or batteries are depleted). The green LED above the 911 button will blink once ever 3 seconds when 911 alerting is active. To cancel the alert, press and hold the 911 button for 3 seconds. The 911 LED will then turn solid red for 5 seconds.

I found SPOT's flashing LEDs confusing at times. For example, there was no way to determine if messages were successfully being sent, or if the unit was receiving GPS signals. An LCD display would have been most welcome, but even a GPS signal LED would have been a big help. I was constantly referring to the manual to lookup what each pattern of flashing lights meant.

Figure 12: Google Map Showing SPOT's Location and Trail

SPOT Satellite Messenger uses its internal antenna to receive GPS signals and transmit L-band over the Globalstar Simplex data network. This provides 2-way communication with the device, even in areas with no cellular coverage.

Globalstar's network is reportedly very reliable and SPOT says they have multiple redundancies built in to the network, including multiple gateways and redundant connections through every link.