Products > Test Equipment
HP 8594E Spectrum Analyzer. At last I own a decent Spec An.
MarkL:
--- Quote from: mattltm on July 14, 2024, 09:05:04 pm ---I only have one error left to resolve and that's a "LO UNLVL" warning on the display. The service manual says:
LO UNLVL (U)(H)
Indicates that the analyzer local oscillator distribution amplifier is not
functioning properly. This message may appear on the 8592L, 8593E,
8594E, 8595E, and 8596E with Options 009/010, Option 009, or
Option 010.
Can anyone give me some pointers on how to fix that?
--- End quote ---
Are you getting any output on your TG? Is it within spec?
Is the unit otherwise operating ok (e.g., you're seeing spectra)?
For the error you're seeing, the Service Manual goes on to say:
--- Quote --- Related Assemblies
A10 LO distribution amplifier (LODA) control/tracking generator control.
Troubleshooting Hints
Check the LO sense and gate bias adjustments on A10. Bias voltages are marked on a label on the top of the high frequency RF.
--- End quote ---
Some references: There is LODA troubleshooting steps on page 419, and useful block diagrams on 387, 389, and 445. A description of LODA operation is on 370.
If you need it, the option 010 tracking generator control board layout and schematics (CLIP) is here starting on page 292 (publication #5963-2951):
https://www.keysight.com/us/en/assets/9018-05708/user-manuals/9018-05708.pdf
The cover page of the above document says 8590A series. It's actually for the 8590E series. This CLIP also represents specific serial numbers, but the differences are usually very minor.
mattltm:
--- Quote from: MarkL on July 15, 2024, 05:29:27 pm ---
Are you getting any output on your TG? Is it within spec?
Is the unit otherwise operating ok (e.g., you're seeing spectra)?
--- End quote ---
Thanks for the info MarkL.
I only see the LO UNLVL error if I set the frequency anywhere below 38MHz. Above that, the error disappears. As far as I can tell, it seems to be working fine. I tuned a VHF filter using a Rigol DSA815 and checked it on the 8594E which gave comparable (albeit better resolution) results.
I'll take a look at the LODA troubleshooting steps and see where I end up!
Navigation
[0] Message Index
[*] Previous page
Go to full version