NorthStar 961 Reference Manual page 350

Chapter 14 - Service and Maintenance Functions
Page 14-6
Adjusting satellite elevation
You can prohibit the tracking of satellites that are close to the
horizon and don't provide high accuracy. The tracking of low
satellites during GPS calculations is used primarily for
technical applications, in which all visible satellites must be
tracked, regardless of how low they're situated.
In other cases, however, when high-precision fixes are
necessary, the advanced user can change this option to hide
any low satellites. This option prevents the use of low satellites
as sources of GPS position information, and avoids potential
errors.
You can adjust this option to 0°, 5°, 8°, 10°, or 15°; however,
Northstar recommends that you leave this option at the
factory setting of 10°.
To change the satellite elevation:
1. At the RECEIVER INFORMATION screen, press the
CURSOR PAD to highlight the MIN SAT ELEV field, then
press the EDIT key.
2. Press the CURSOR PAD left or right to select either 0, 5, 8,
10, or 15 degrees.
3. When done, press the ACCEPT key, or CANCEL to leave
the option unchanged.
Viewing the GPS software version
The software version of the GPS receiver is indicated in the
GPS RCVR REV field.
Setting DGPS operation
You can enable or disable the use of differential information.
1. At the RECEIVER INFORMATION screen, press the
CURSOR PAD to highlight the DGPS SYSTEM field, then
press the EDIT key.
961/962 Operations and Reference Manual, Rev. A