HP ESA-L1500A, User'S And Calibration Manual

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18 Chapter 1
Preparing for Use and Printing
Turning on the Analyzer for the First Time
Turning on the Analyzer for the First Time
When you turn on the spectrum analyzer, you will see the message
“
Doing Initial Alignment
” on the display. This tells you that the
instrument is performing a portion of its automatic alignment.
To make sure your spectrum analyzer meets specifications, allow a 5
minute warm-up before making calibrated measurements.
NOTE
It is normal to hear clicking when the Auto Alignment function is on.
During the interval between sweeps portions of the spectrum analyzer’s
circuitry are realigned. Some of the circuitry is controlled by relays. It is
the rapid switching of these relays between sweeps which causes the
clicking sound. Under normal operation, these relays will last over 50
years.
To eliminate the clicking sound, turn off the automatic alignment. (See
the
Alignments
key description in Chapter 4.) The Align Now All
function should, however, be performed periodically. For more
information on how often to perform Align Now All when the Auto
Alignment function is off, refer to Chapter 7, “Specifications.”
If you wish to use an external 10 MHz source as the reference
frequency, connect an external reference source to the
10 MHz REF IN
connector on the rear panel. The signal level should be greater than –15
dBm.
Perform the following steps:
1. Before using your spectrum analyzer, make sure it meets operating
temperature conditions.
2. Plug the power cord into the spectrum analyzer.
3. Press I (the On key).
After a few seconds, the screen will display the firmware revision
date in the YYYYMMDD format. For example, Rev 19970522
indicates revision May 22, 1997.
NOTE
Record the firmware date and keep it for reference. If you should ever
need to call Hewlett- Packard for service or with any questions
regarding your spectrum analyzer, it will be helpful to have the
firmware date readily available.
If your spectrum analyzer is equipped with Option A4H (HP-IB and
Parallel interface), the interface address (
HP-IB ADRS: XX
) also
appears on the screen.
If your spectrum analyzer is equipped with Option 1AX (RS-232 and
Parallel interface), the baud rate (
RS232: XXXX
) is displayed.