Symmetricom 5115A, Руководство по эксплуатации и обслуживанию

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5120A/5115A Operations and Maintenance Manual 73
To calibrate the internal reference oscillators:
1. Set the test set's system date and time if necessary, as calibration information is time
stamped.
„
To check current system time see “4.1 The Settings Screen” on page 21, to set system
time see “4.1.1 Setting Date and Time” on page 22 for details.
2. Detach any signal connected to the Reference port.
3. Attach a calibration lab quality 10 MHz signal to the Input port.
4. Press Settings and Options , then Options , and finally Internal Reference to access the
calibration screen.
Note
This screen can be accessed to retrieve current calibration information regardless
of attached signals or collecting state.
5. Start data collection and wait at least 17 minutes for the 1000 second frequency average
used to calculate the internal oscillators' frequencies.
„
While the internal reference screen is active, the 5120A-01 periodically attempts
calibration data calculation. Calculation results or conditions that prevented the
calculation are reported in the Pending Calibration frame. When the Pending
Calibration frame presents the measured frequencies, the test set is ready to store the
oscillator calibration values (proceed to the next step)
6. Press Calibrate to store frequency calibration data.
„
Calibration frequencies are calculated, and stored. The Previous Calibration frame
updates to reflect newly calibrated frequencies and time of calibration.
8.1.1.2 Calibrating 5120A-01 Internal Reference Remotely
To retrieve current internal reference calibration data remotely:
1. Access the Command port. See “7.1 Accessing the PNTS Remotely and Exiting the
Remote Session” on page 58.
2. Issue the calinfo command.
„
The 5120A-01 returns date and time of calibration and the calibrated frequencies of
both internal reference oscillators.
To calibrate the internal reference oscillators remotely:
1. Detach any signal connected to the Reference port.
2. Attach a calibration lab quality 10 MHz signal to the Input port.
3. Access the Command port. See “7.1 Accessing the PNTS Remotely and Exiting the
Remote Session” on page 58.
4. Set the test set's system date and time if necessary, as calibration information is time
stamped.
„
Run the show date command to check, and set date command to set the system time.