Power tab, Urban canyons, Power tab -8 – Hand Held Products 7900 User Manual
Page 166: Urban canyons -8, Check the
11 - 8
Power Tab
You can verify if the GPS module is receiving power from the I/O connector on the Power tab.
If 5V Power=ON, the 8th pin on the terminal’s
(see page 11-2) is powering out and the GPS module is receiving.
Enable 5V Out
This button is active only if the GPS module is not currently powered.
Tapping it activates the power out from the I/O connector.
Disable 5V Out
This button is active only if the GPS module is currently powered.
Tapping it deactivates the power out from the I/O connector.
Urban Canyons
GPS signals can be obstructed by objects on the ground, from buildings to trees. This is called the urban canyon problem
because it occurs primarily in cities where there are more objects on the ground. GPS performance in an urban canyon
environment is dependent upon the ability of the GPS module to "see" enough satellites in the satellite constellation.