Performance veri
fi
cation
Internal frequency
calibration test
Perform the following procedure to set the internal frequency of the base unit
internal oscillator. This adjustment stores the current correction to the oven
oscillator frequency while is it locked to a GPS, GLONASS or reference signal,
to be used when in
Internal
mode. It can be done without any disruption to
operation and is best done in the operating environment of the instrument.
1.
Connect the power cord to the SPG8000.
2.
Check for error messages as the instrument starts.
3.
Connect a GPS or GLONASS signal to the GPS ANT connector.
Figure 24: Setup for internal frequency calibration
4.
Allow the instrument to warm up for at least 20 minutes.
5.
Check that the signal on the SPG8000 under test is locked as follows:
a.
Press the
STATUS
button.
b.
Press the down (
▼
) arrow button until you see
STATUS : REFERENCE :
GPS
.
c.
Check that
Locked >>>>
shows on the display.
6.
Go to the diagnostics page on the SPG8000 under test and check that the
system is in
Fine
mode as follows. If it is not, then allow it to warm up and
stabilize.
a.
Press the
SYSTEM
button.
b.
Use the up (
▲
) arrow button to select
DIAGNOSTICS
.
c.
Press the
ENTER
button.
d.
Check that you can see
SYSTEM : DIAGNOSTICS : TUNE
in the
menu.
e.
Press the right (
►
) arrow to display the
Phase
and
DDS
values.
f.
Check that
Fine
shows to the right of the readings. If it does not, allow
more time for the system to stabilize.
7.
Press the right (
►
) arrow to display the
Tune
values.
86
SPG8000 Speci
fi
cations and Performance Veri
fi
cation