Adjustment Procedures; Adjust Master Clock Using A Frequency Signal Generator - Tektronix SPG8000A Service Manual

Adjustment procedures

Adjust master clock using a frequency signal generator

SPG8000A Master Sync / Clock Reference Generator Service Manual
This section provides procedures for the adjustments that can be performed by
trained service technicians.
CAUTION.
All Adjustment procedures are to be performed only by trained service
technicians.
NOTE.
Master clock. There are three methods for adjusting the frequency of the
master clock. You can use a frequency signal generator, if Option GPS is installed
you can lock the master clock to a GPS or GLONASS signal, or if Option PTP is
enabled, you can lock the master clock to a PTP signal. Procedures for all three
methods are included in this section.
If your SPG8000A generator has Option GPS installed you can adjust the clock
while the instrument is in operation, which avoids any system downtime or any
warm-up period.
If your instrument does not have Option GPS installed, you must remove the
instrument from service in order to adjust the master clock using a frequency
generator.
Earlier versions of the GPS module can receive only GPS signals. Later versions
of the GPS module can receive both GPS and GLONASS signals. (See page 8,
How to determine which GPS receiver is installed in your instrument.)
Use this procedure to adjust the frequency of the master clock if you do not have
Option GPS installed in the instrument under test. This will require a reference
SPG8000A with Option GPS installed (or equivalent test equipment).
Warm-up period. Allow a 20 minute warm-up time in a +20 °C to +30 °C
environment before making this adjustment. The reference SPG8000A unit
must be hooked to an external antenna, GPS or GLONASS signal during the
warm-up period.
Adjustments done before the operating temperature has stabilized may cause
errors in performance. In addition, the signal generators require appropriate
warm-up time to meet the frequency accuracy.
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