HP 8901B Operation And Calibration Manual page 118

5-2
RF Frequency and Fiequency Error
RF Frequency
and Frequency
Error
If
you
need
to
know:
Refer
to:
A
way to accurately characterize the
frequency response of an RF device
.
Output Flatness (5-2)
A
way to quickly measure
multi channel transmitters
. .
.
. .
.
. . . .
A
way to measure frequency accuracy
in parts-per-million PPM)
.
.
.
.
. . . . .
Multi channel Testing (5-3)
Frequency Error (PPM) (5-3)
A
way to measure signals above
1300 MHz using an external
LO mixer
. . . . . . . . . . . .
.
.
.
. . . . .
.
.
.
. . . . .
Frequency Offset Mode (5-4)
Output Flatness
The following procedure demonstrates a way to use the HP 8901B
to characterize the frequency response of RF devices. This technique
enables you to accurately characterize output flatness from
100 kHz to 2.6 GHz at levels between -20 and +30 dBm.
RF signal source. Adjust the source to the frequency at which you wish to
establish the reference level.
2.
Select the RF Frequency measurement and press the green
AUTOMATIC
OPERATION
key on the
HP
8901B.
3.
When the
HP
8901B displays the frequency of the input signal,
select RF Power on the
HP
8901B. The previous frequency
measurement enables the instrument to automatically select the
correct calibration factor for its power measurement. (Use the
LOG/LIN key
if
you wish to toggle between Watts and dBm units.)
reference level.
Frequency measurement on the
HP
8901B.
1 . Connect the
HP
8901B and Sensor Module to the output of your
4.
Press the
RATIO
key. This establishes the current measurement level as the
5.
Change the frequency of the signal source, and re-select the RF
6 . When the
HP
8901B displays the input frequency, select RF Power.
7. Press the Blue Shift key and then the
PREVIOUS RATIO (RATIO)
key
to reference this measurement to the reference level previously set in
step
4.
frequency range of your device.
8. Repeat steps 5 , 6 and 7 to check output flatness across the output