Anritsu 373XXA - Manual (Page 93)

6-7
A8 ADJUSTMENT
(37397A) The adjustments are important to the operation of the VNA above 56
GHz. Improperly adjusted A8 Potentiometers may cause lock failures.
Perform these adjustments as follows:
q The A8 PCB is replaced.
q 44733 Buffer Amp is replaced.
Calibration
Procedure
Perform the following steps:
Equipment Required
None
NOTE
Allow the 373XXA to warm-up at least 30 minutes prior to
performing calibration, and perform the ALC calibration
(paragraph 6-3) before doing this calibration.
Procedure
Step 1. Connect a V Throughline (3670V50-2 with FF Adapter) be-
tween Ports 1 and 2.
Step 2. Set the 373XXA to sweep from 50 to 65 GHz.
Step 3. Set RF power to 0 dB (default value).
Step 4. Using Diagnostics menu, view Non-Ratio parameters.
Step 5. View Channel 1 (Ref A) only, and activate Autoscale.
Step 6. Adjust the “RA” potentiometer on top of A8 for the flattest
trace display. A small discontinuity at 56 GHz is normal.
Step 7. Perform Step 6 for each of the four Non-Ratio channels.
Post Calibration
Actions
After the calibration process is completed, perform the following ac-
tions, as appropriate:
If calibration passes:
Save the calibration data to (hard) disk, as follows:
Step 1. Press the Option Menu key (Enhancement key group) to dis-
play the OPTIONS menu.
Step 2. Select DIAGNOSTICS from menu.Then select in se-
quence: H/W CALIBRATIONS |DISK OPERATIONS
|SAVE TO HARD DISK|HW_CAL.SLT.
ADJUSTMENTS A8 ADJUSTMENT (37397A)
373XXA MM 6-13