HP 70427A User Manual page 559

NOTE
Performance Tests
Test 6 - Phase Noise and Spurs of Downconverter
Measure the reference source output with a power meter and if necessary,
adjust it to +10 dBm ± 0.5 dB. Disconnect the cable at the DUT's input
connector and connect the power meter to the end of the cable.
Adjust the DUT's output power for +10 dBm, ±0.5 dB.
a. Press the
Output
b. Press the
Power
c. 3. Adjust the power with the knob (0.1 dB steps) or the Up/Down
arrow keys (1 db steps).
When entering 0.1 dB steps the actual power may change as much as 0.2 dB.
d. If necessary, make the DUT module active by pressing the
key followed by the
display the module's softkeys.
6. Set the DUT input frequency to 25.8 GHz
a. Press the
Freqs
b. Press the
INPUT FREQ
c. Enter 25.8 with the numeric keypad.
d. Press the softkey.
GHz
7. Run the phase-noise measurement
When the phase-noise measurement program stops to prompt a zero-beat
adjustment, do the following:
a. Make sure the HP 70428A Option K01 is turned ON.
b. Adjust the pot on the HP 70428A Option K01 for a zero beat within
50 kHz. If necessary, switch the NORMAL/REVERSE switch and
turn the pot in the other direction.
c. Press softkey to continue measurement.
Proceed
On the HP 3048A controller press the
14-48 HP 70427A/HP 70428A User's Guide
softkey.
softkey.
softkey. Press the
NEXT INSTR
softkey.
softkey.
and the
SHIFT
Display
key to
MENU
softkey.
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