Magellan GPS PROMARK X, User Manual

Page: 103 / 188

Differential ProMARK X
7-11
Press the DOWN ARROW or ATR key
to assign attributes at any time during a
defferential session. The attributes will
be put at the head of the file (Attribute
entry is described in Chapter 6.)
FIL:1203S001.STA
TYPE:PSEUDO
MODE:3D
!
ATTRIBUTE:
TREE 03
PRESS ENTER !
AVG PDOP 1.1
2 1 1 0 0
5 5 2 2 9
To view the status screen, press the
RIGHT ARROW . File status includes
the filename, the type of file, and the
mode of operation.
You can also view the receiver status by
pressing the right arrow again. This will
show you which satellites are being
used by the receiver to compute files,
their signal strengths at the receiver,
and whether or not you are locked onto
a satellite. It is recommended that you
check this screen shortly after you ini-
tiate logging to make sure you are get-
ting complete signal information from
the satellites.
After you’ve pressed ENTER to START LOGGING, you will experience a delay
between 10 seconds and 2 minutes before the counter begins. The receiver
will acquire lock on all the specified satellites and then download ephemeris
data. After this, the receiver’s counter will begin. To STOP LOGGING press
ENTER from the STOP LOGGING screen. The screen will prompt you to either
press ENTER to stop or press CLEAR if you wish to continue the session. Upon
pressing ENTER, the receiver will display a message that the session was
stopped as well as how long the session was.
At this point you may want to know how long your pseudorange session
should be collected. As a rule, plan on logging for 3– 5 minutes at a 1 second
data sampling rate to achieve 2 – 5 meter accuracy. If sampling rates are set
to something other than 1 second, you will need to occupy the point for a
longer period of time. It is recommended that occupation time be multiplied
by t for every t second increase in the sampling rate. Again, be sure that both
the control and remote receivers are using the same data sampling rate and
the same satellite sets.