HP ESG Series, Руководство пользователя

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2-4
Using Functions
Setting Frequency and Power Levels
To Set the RF Output Power Level
1. Press Preset to return the signal generator to the factory-defined instrument state.
2. Observe the amplitude area of the display (in the upper middle of the display). It should
display
−
135 dBm. This is the normal preset RF output power level.
3. The signal generator is set to output an RF signal, however the RF On/Off key must be
set to On before the RF signal is available at the RF OUTPUT connector. Press
RF On/Off . Notice that the display annunciator changes from
RF OFF
to
RF ON
. The
RF signal is now being output at a
−
135 dBm level at the RF OUTPUT connector.
4. Change the power level to
−
20 dBm. Press Amplitude . The current power level is now
displayed in the active entry area of the display. Using the numeric keypad and the
key, enter
−
20 and then press the dBm softkey. The new
−
20 dBm RF output
power is now displayed in the amplitude area of the display and also in the active entry
area.
5. Amplitude is still the active function until you press another front panel function key.
You can also change the amplitude using the up and down arrow keys and the front
panel knob. Practice changing the amplitude using these methods also.
To Set an Amplitude Reference and an Amplitude Offset
The following procedure sets the RF output power as an amplitude reference to
which all other amplitude parameters are relative. The amplitude initially shown
on the display will be 0 dB (the power output by the hardware minus the reference
power). Although the display changes, the output power does not change. Any
subsequent power changes are shown as incremental or decremental to 0 dB.
1. Press
Preset
to return the signal generator to the factory-defined instrument state.
2. Set the RF output power to
−
20 dBm.
3. Turn on amplitude reference mode and set the current output power (
−
20 dBm) as the
reference value. Press
Ampl
,
More (1 of 2)
,
Ampl Ref Set
. The amplitude displayed is
0 dB (the power output by the hardware,
−
20 dBm, minus the reference value,
−
20 dBm.) Notice that the
REF
indicator is turned on and the
Ampl Ref
softkey has
toggled to
On
.
4. Set the
RF On/Off
key to
On
. Notice that the display annunciator has changed from
RF OFF
to
RF ON
. The power at the RF OUTPUT connector is
−
20 dBm.
5. Use the up arrow key to increase the output power by 10 dB. The amplitude display
changes to show 10 dB (the power output by the hardware,
−
20 dBm + 10 dBm, minus
the reference power,
−
20 dBm) and the output power changes to
−
10 dBm.