[SOLVED] HP 8594E - AMPTD CAL : EMI Bandwidth taking forever

[Synoptic]

[I was using a defective N to BNC adapter which ALSO was a 75 Ohm adapter. Calibration is all good now with the right material used.]

Hi ! a bit of a newbie here. I have a 8594E that cannot CAL it's amplitude.

I read on the forum that the option 130 could be an easy cause to check by removing it. I also read I must jump a connection when the card is removed. Is it the case, if so, what do I jump ?
Thank you.

Once I can run the analyzer without that option card, I'll come back with more detail if the error is still present.

Oh, and I think I destroyed the fan circuit by plugging the audio jack connector into it, which had the effect to short the power pins. <-- Should be an easy fix, right ?

Looking for the schematics that will help me fix the fan.

[Synoptic]

Update : I found that the fan is directly driven from PIN 8 of the PS connector. Digging into this right now.

I still would like to know how to make the analyzer work without the Option 130 board.

Thanks

[Synoptic]

Alright, the 3/8 A fuse is blown in the PS. going to replace that.
Now on the Option 130 thingy...

[MarkL]

The Assembly Level Service Manual has a section on Option 130.  Most notably it says "jumper W1 must be removed when Option 130 is installed in the analyzer".  Presumably you need to put this jumper back if the board is not installed.

More details on how the signal routing works for this board in Chapter 9, pages 378-379.

  https://xdevs.com/doc/HP_Agilent_Keysight/08590-90316.pdf

[Synoptic]

The Assembly Level Service Manual has a section on Option 130.  Most notably it says "jumper W1 must be removed when Option 130 is installed in the analyzer".  Presumably you need to put this jumper back if the board is not installed.

More details on how the signal routing works for this board in Chapter 9, pages 378-379.

  https://xdevs.com/doc/HP_Agilent_Keysight/08590-90316.pdf

Thank you!

I looked for that jumper, didn’t see it!

[Synoptic]

I found where W1 is : On the LOG AMPL board.
Doing the AMPTD CAL now to see.

[Synoptic]

Ok, it's not the option card.
Manual says this :

Code: [Select]

CAL: GAIN FAIL (H)
During the CAL AMPTD routine, the amplitude of the video signal at the
ADC on the A16 processor/video assembly is too low. The error message
appears when the reference-level-calibration DAC, located on the A7
analog interface assembly, has been adjusted to its maximum of 255,
and the amplitude of the video signal remains below tolerance.
Related Assemblies
8590L and 8591E spectrum analyzers only: A3 input attenuator, A4
first converter, A5 second converter, A6 YTO, A7 analog interface, A9
third converter, A11 bandwidth filter, A12 amplitude control, A13
bandwidth filter, A14 log amplifier.
All other 8590 E-Series and L-Series spectrum analyzers: A3 front end,
A7 analog interface, A9 third converter, A11 bandwidth filter, A12
amplitude control, A13 bandwidth filter, A14 log amplifier.
Troubleshooting Hints
The CAL AMPTD routine checks the amplitude of the video signal as it
adjusts the A7 reference-level-calibration DAC. Normally, the
video-signal amplitude should move within tolerance as the A7 DAC
changes the gain of the IF calibration amplifier on the A9 third
converter assembly. Figure 9-1, IF/Control Overall Block Diagram, and
Figure 9-2, Figure 9-3, or Figure 9-4, RF Section Overall Block Diagram
for more information.
Check the signal amplitude along the signal path from the RF input,
through the IF section, to the output of the A14 log amplifier. Refer to
“Isolating an RF, LO, IF, or Video Problem” in Chapter 4 for further
troubleshooting information.

[Synoptic]

Could a corrupted / bad RAM CAL data cause this issue ?

[Synoptic]

I found this video on the tube :

After entering -37Hz, the AMPTD CAL is going passed where it usually tops. However, the CAL is still running and it is going through negative Frequency in the EMI bandwidth cal. It started at 2.9Ghz (mine is a 2.9), and is now at -57Hz. Weird.

[Synoptic]

I found this thread on Keysight's forum about the same issue : EMI Bandwidth taking forever. However, I cannot understand what the solution is by reading the thread :

https://community.keysight.com/forums/s/question/0D52L00005IdwyfSAB/8594e-cal-emi-badwith-runs-for-ever?topicId=0TO2L0000001TtSWAU&topicName=Signal%20Analyzers

[Synoptic]

Found out my N to BNC connector had a fault.
I am now back to the AMPDT : GAIN FAILED ! Which is kinda good news.

I guess now I'll need to open the device and fix whatever is connected to the DAC..