Keysight (Agilent) 8711A Service Note

8711A-05

SUPERSEDES: NONE

Continued

DATE: August 1994

8711A Network Analyzer

Serial Numbers: 0000A00000 / 9999A99999

Change in adjustment procedure for all instruments with firmware
Revision A.02.10

Situation:

Firmware revision A.02.10 for the 8711A has a problem with adjustment #104 (ALC
Correction) that could prevent the user from having any control over the RF power level
when completed. The symptom is maximum RF power is always output regardless of the
power level requested. This level is typically +20 dBm or more. This problem will appear
if Adjustment #104 is performed while any correction constants are stored in EPROM.
Unfortunately, this is generally the case for any previously calibrated 8711A.

1 of 2

AUTHOR:

JV

ENTITY:

5300

© 1994 AGILENT TECHNOLOGIES
PRINTED IN U.S.A.

SERVICE NOTE

ADMINISTRATIVE INFORMATION

INFORMATION ONLY

SERVICE NOTE CLASSIFICATION:

ADDITIONAL INFORMATION:

Page 2 Service Note 8711A-05

Solution/Action:

Fortunately, avoiding this problem is very simple. Before running #104, store any
Correction Constants (CC) to disk. Then insert the firmware disk and cycle power to re­install the firmware; resulting in all CC EPROM data being erased. Insert the CC data
disk you just made and press “Load CC From Disk”. DO NOT press “Install CC Data
from Disk” or “Store CC to EPROM”. You are now ready to continue with adjustment
#104 and all remaining adjustments. When all adjustments have been completed, store
the CC data to disk again. To permanently store them to EPROM, press “Store CC to
EPROM”.

To verify that the results of adjustment #104 are valid, press PRESET, CHAN1,
Detector Options, Narrowband Internal, R. The observed trace should be within about 5
dB of 0 dBm. If it is above +15 dBm, then the test was not done properly; repeat the
procedure beginning with step 1 below.

Rev 2.10 Procedure Summary for Adjustment #104 (ALC Correction)

1. Load firmware

2. Load CC from disc if avilable (see not below)

3. Perform adjustment #104 (and any others if needed)

4. Store CC to disc

5. Store CC to EPROM

Note

If you will be performing ALL adjustments, skip step 2.