[SOLVED] HP 8594E - AMPTD CAL : EMI Bandwidth taking forever - Page 1
Forum section: electronics / repair

author: Synoptic
author_rank: Contributor
timestamp: January 13, 2022, 07:07:01 pm
content: [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.

author: Synoptic
author_rank: Contributor
timestamp: January 14, 2022, 03:48:51 pm
content: 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

author: Synoptic
author_rank: Contributor
timestamp: January 14, 2022, 04:05:06 pm
content: Alright, the 3/8 A fuse is blown in the PS. going to replace that.Now on the Option 130 thingy...

author: MarkL
author_rank: Unknown
timestamp: January 14, 2022, 05:47:41 pm
content: 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

author: Synoptic
author_rank: Contributor
timestamp: January 14, 2022, 06:30:59 pm
content: Quote from: MarkL on January 14, 2022, 05:47:41 pmThank you!I looked for that jumper, didn’t see it!

author: Synoptic
author_rank: Contributor
timestamp: January 14, 2022, 10:09:31 pm
content: I found where W1 is : On the LOG AMPL board.Doing the AMPTD CAL now to see.

author: Synoptic
author_rank: Contributor
timestamp: January 14, 2022, 10:21:14 pm
content: Ok, it's not the option card.Manual says this :Code:CAL: GAIN FAIL (H)During the CAL AMPTD routine, the amplitude of the video signal at theADC on the A16 processor/video assembly is too low. The error messageappears when the reference-level-calibration DAC, located on the A7analog interface assembly, has been adjusted to its maximum of 255,and the amplitude of the video signal remains below tolerance.Related Assemblies8590L and 8591E spectrum analyzers only: A3 input attenuator, A4first converter, A5 second converter, A6 YTO, A7 analog interface, A9third converter, A11 bandwidth filter, A12 amplitude control, A13bandwidth 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, A12amplitude control, A13 bandwidth filter, A14 log amplifier.Troubleshooting HintsThe CAL AMPTD routine checks the amplitude of the video signal as itadjusts the A7 reference-level-calibration DAC. Normally, thevideo-signal amplitude should move within tolerance as the A7 DACchanges the gain of the IF calibration amplifier on the A9 thirdconverter assembly. Figure 9-1, IF/Control Overall Block Diagram, andFigure 9-2, Figure 9-3, or Figure 9-4, RF Section Overall Block Diagramfor 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 furthertroubleshooting information.

author: Synoptic
author_rank: Contributor
timestamp: January 16, 2022, 02:39:56 pm
content: Could a corrupted / bad RAM CAL data cause this issue ?

author: Synoptic
author_rank: Contributor
timestamp: January 16, 2022, 05:15:01 pm
content: 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.

author: Synoptic
author_rank: Contributor
timestamp: January 16, 2022, 06:11:42 pm
content: 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

author: Synoptic
author_rank: Contributor
timestamp: January 17, 2022, 05:54:54 pm
content: 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..