Sensitivity - HP 70427A User Manual

20
Table 5-1
Table 5-2
Tuning Sensitivity
Source Tuning DUT Max

Sensitivity

Drift
.05 ppm/V 2X10
1 ppm/ V 1 ppm
20 ppm/V 20 ppm
The DUT max drift column of the table shows how much the DUT
frequency can drift and be tracked by the HP 70428A Option 002.
If the HP 70428A Option 002 frequency is within ± 10 MHz of the DUT
frequency, the HP 70428A Option 002 can be tuned by stepping the
frequency of the HP 8662/3A. If the HP 8662/3A frequency must be
changed more than 10 MHz in order to get the HP 70428A Option 002's
frequency close enough to the DUT frequency, press the
softkey to re-peak the HP 70428A Option 002's Yig-Tuned-Filter.
Enter the tuning sensitivity as follows:
1. Press the softkey.
Ref Chain
2. Press the
Tune Sens
3. Press the ,
0.05 ppm/V
Step - 6 Change the source's PLL bandwidths if needed
A change in one of the default bandwidths is necessary if the source is being
tuned using the 0.05 ppm/V or 1.0 ppm/V tuning sensitivity and the
HP 3048A system PLL bandwidth is not much less than the HP 70428A
Option 002's default bandwidths. The following table shows reference chain
configuration and default bandwidths for each tuning sensitivity.
HP 70428A Option 002 Reference Chain Parameters
Tune Osc. PLL
Sens Tuned
0.05 10 MHz 100
ppm/V MHz
1.0 100 MHz 600
ppm/V MHz
20 ppm/V 600 MHz none
Phase Noise Measurement With PLL
-9
softkey.
, or softkey.
1.0 ppm/V 20 ppm/V
Default PLL
BW
126 Hz
10 kHz
n/a
HP 70427A/HP 70428A User's Guide 5-5
Tunable Source Operation
RETUNE YTF