HP 8596E Spectrum Analyzer Frequency & Amplitude Self Calibration After Dead Battery
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- Опубліковано 8 вер 2024
- Error condition displayed on screen while trying to do AMPL Cal is: RES BW AMPL FAIL
A simple, step-by-step, procedure that Might help you resolve the error you get from a dead battery on some HP spectrum analyzers.
Brother, I’ve had an 8593 on my bench for a year with the same problem. This fixed it! Thank you so much for taking the time to record this and post it.
You just made my effort worth while. I really appreciate you letting me know. Really confuses me that this information can not be found in that massive HP manual. It should be the first page of testing and calibration.
CAL FREQ -37hz is, in fact, the unlock code as you suspected. Those manuals are fantastic. I'm 35 and they started phasing out component level manuals for board level repairs when I started to get into the jive of things. If you don't know the principle of operations, I can see how it can be frustrating though. Sit down with a coffee on a rainy weekend and start with the text of the PoO, then go to the block diag, and finally the schematics. In general, the service manuals (not to be confused with the owners manual) will even have full flow diagrams, directing you from "If error code, try.."
Oh and RF coil is to tune the oscillator. Like, consider the YIG as though it's the "coarse" knob, and RF as though it were the "fine" knob. (This analogy also holds true for NMR machines)
👍🏻 ❤️ THANK YOU!!
Someone visiting my shop accidentally deleted the onboard calibration details stored in my SA. (8951c)
Now the SA is displaying frequencies off by 40-70 MHz..
I will be trying this first thing in the AM.
Note the procedure detailed here will NOT restore all of the analyzer calibration information that will be lost if the battery fails. The analyzer also has frequency response flatness correction constants, timebase correction constant (units without the ovenized master oscillator only), step gain correction constants, and correction constants for the tracking generator if present. There is a procedure in the service manual to write down these correction constants so that they can be restored if the battery fails. See page 199 in the service manual. If your analyzer has not had a battery failure so the correction constants noted here are still valid you should do this soon to prevent loss of this information. The errors if the frequency response correction information is lost can be as big as 11.5dB in my 22GHz 8593E. One further note: in addition to performing the CAL FREQ and CAL AMPTD noted in the video see page 209 in the service manual.
I will take another look at this. Thank you. Finding anyone with good advice on a piece of equipment like this is very rare. I do still use it occasionally but as I remember back, I think I remember the amplitude calibration being off - I think a bit low... I am writing without examining it yet but at least the darn thing started working again if only in a relative amplitude mode. I think the frequency calibration is OK. I did not write down any constants before the battery failure so if they are lost then that is the end of that. I will check out the pages you noted. Thanks again.
Used to have the 8591e I think it was with built in tracking generator, nice thou it was I finally bought the Siglent 2021x analyzer & I don't regret it, it's superb, more versatile in many ways to the old hp & a hell of a lot lighter! Useful when I want to take it in the garden to do antenna measurement
This thing is heavy and as I mentioned is much more inclined to be used at higher frequencies than HF but it is a beautiful instrument and the accuracy, as it relates to all my other RF equipment is right-on. Nowadays with the SDR equipment, we don't need the old Collins R-390 or huge 1980's vintage SA equipment like this HP but it seems necessary for me to try to keep it running as long as I can. The day I can'f fix it will be the day it moves one step closer to the recycle bin.
Thank you for taking the time to put these very usfull videos for people to learn about amplifiers and other instruments. I have gained a great deal of knoledge. Thanks to you and uncle doug and blueglow electronics I'm building my own audio tube amps .and also have fixed amps for local bands thanks again
George, your comments are very encouraging and spur many of us that post videos onward to continue to share our experiences with the world as useful or flawed as they may be. Discovering all the ups-and-downs, all the what-works-and doesn't- work is what the technical community is all about. Discovering this in the vacuum of a lab, all alone, and not sharing it is worthless and a sad ending. Theory and the regurgitation of academics is far too common in books and UA-cam. The details of academics is important and is what makes the marvel of technology work for us today but knowing the difference between voltage and current is essential. It is a labor-of-love to try to effectively document experiences and capture that essence to post to everyone. I feel even if I contribute the least significant detail, all the effort was worth it. Please stay safe and enjoy, and go forward with your passion.
Thanks for this I have that exact unit on my bench. Extremely useful to know, thanks.
That set of magic push buttons to allow it to self calibrate are almost hidden in the manual. I think that should be a procedure of the first paragraph in the calibration section.
I am really disappointed it took me so long to solve this issue and is why I posted this video. If you ever need it, I hope it helps save your SA - it is a magnificent instrument and I will be using it this week on a project with my son.
thanks so much for this video.the reason they don't tell you this is so you have to take it to a tec for a cost.
It kind of seems so - but where would a person send a vintage device like this without having to pay $$$$ and still get just another geek like us to look at it? Factory replacement and alignment surely went away many years ago. I guess we are just supposed to come up with another $80,000 for a new one. I hope the video helped you.
Hope you are well.
I love HP instruments and have several on my bench. I really pondered going for an older HP spectrum analyzer vs the Siglent line. The money is close enough that cost isn’t the criteria. I just can’t justify going with a used HP that uses older analog technology and where parts may become impossible to source, vs a brand new digital SA. I can’t pass up the new unit. It also has capabilities that HP does not offer.
Bill,
I understand what you are saying. When this thing seriously goes on-the-blink, its days will be over... if I can't fix it, I doubt I can pay someone else to do it for me short of someone with a few laying around for spare parts and would I really trust that for true calibration? And the price they would want? I don't think so. What cost $80K thirty years ago, may be able to be bought today for $4K or about the price of these vintage instruments. That has been my comment several times concerning the HP 3580A audio spectrum analyzer - 40 years old - buy a PC based, external USB sound card FFT software program. Some are even free off the Internet and they work very fast at low frequencies whereas the 3580A takes 10 minutes to trace one 20 Hz plot. On the other hand, maybe as a younger fellow I just had a love afire with these magnificent instruments and I am Very pleased that I finally found the magic-touch buried deep in the books to have it cal again. Even at the end it has been pointed out by a very observant viewer that it got an error: "Cal: 00 DAC Failed" I can't find what that means and I can verify that vertical and horizontal are perfect so I will just have to let it go.
Thank you for posting this video! I had the same problem with a dead battery on a 8591a and this got it through the cal!! SUB:)
I am very pleased to know it helped you.
Thank you! thoroughly enjoyed this useful videos. I have an interesting topic request for a future video, which I hope you could consider covering.
In many evaluation situations in both RF and AF world, we need to find/evaluate a test equipment say a amplifier or buffer and need to define its 2nd harmonic content both magnitude (absolute or relative to fundamental) as well as 2nd harmonic Phase angle (with respect to fundamental frequency).
I wanted to ask you… can you do a video on that topic?? Finding amplitude and angle of a second order harmonic? I know finding the amplitude is easy with a spectrum analyzer (Nyquist, FFT plot). BUT how can we find & isolate phase angle of 2nd harmonic with respect to fundamental frequency in output of an amplifier??? I appreciate if you can do a video suggesting/demonstrating a working solution. It may be fun just to investigate for heck of it… All the best.
I never thought of the phase of the second harmonic in relationship with the fundamental. I will have to think about that one. Just guessing but maybe a precision measurement from leading edge of fundamental to same spot on harmonic? Take a look at this link.
music.stackexchange.com/questions/85874/harmonic-series-phase-difference
Hi David, I hope you are okay. It has been a month since you last posted a video so I've been worried. I know you folks had bad weather in February. Anyhow, take care and please let us know you and your family are doing okay.
Hi Stephen,
All is well here. We got our vaccinations and are ready to get past this last year's event. I have a couple of items that I want to make videos of. One is a 829B push-pull VHF, 2 meter, class-C amplifier I built about 35-40 years ago. It uses any HT that can produce 1.5 watts or so and amplify it up to 70 watts or more. It is a really classic design that most Ham radio operators have seen in the ARRL books. Also, I want to post another video of my AM station I run on 40 meters now that I have the Collins R-390 installed in the rack. This would be a dream-station of the 1960's... lol, the R-390 may not have been available that long ago as it was a top-secret radio in its early days. Stay safe and thanks for thinking of me.
I like your videos, thank you.
At 12:42 it says "Cal: 00 DAC Failed". Does it mean anything?
Wow... I didn't notice that. I will look into it and it happened exactly as it finished.
I looked for that error and do not know what it means. It seems to have pointed in the direction of attenuator calibration ( ? maybe). In any case, it is back to "normal" with perfect vertical (amplitude) and horizontal (frequency) calibration. I know this is not a video for the masses but I have seen quite a bit of information on the Internet about how to get these instruments to self-cal again after battery loss and no one has made a video of how to do it or what worked for them.
The procedure is mentioned here at the HP website on page 209 at the bottom of the page: www.keysight.com/upload/cmc_upload/All/08590-90316.pdf
I just tried the link and Keysight makes this site no longer available... 10/11/2023
I have an unrelated question. I accidentally plugged a 100 watt Marshall amp's speaker cable into a Marshall 60 watt head speaker output. The 100 watt head was on while the 60 watt head was not. The 100 watt head was on for less than a minute when I realized what I had done and I turned it off. Everything seems okay. As I've played both amps since then. I was wondering what damage could have occurred to either amp had I left this on longer?
I am sure you are OK. Amplifiers usually only become damaged if there is no speaker load at all on the output and the amplifier is played at full volume. Mismatched speaker loads, i.e. an 8 ohm load on a 16 ohm output or the other way a round is not going to do any damage, even at full volume. I am sure your amps were not harmed.
@@ElPasoTubeAmps Thank you.
Btw: The - FREQ 37 HZ. and FREQ -2001 HZ are “passcodes”
This is great to hear. If my video helps save even one of these magnificent SA's, yours, it was all worth it. It surprises me that this information is only for those willing to go to extremes to learn a procedure that should be the first line in restoring one of these instruments to working order after a minor event. Please let me know if this solves your issue. Best of luck.
I like the talking. LOL
Thanks... I just can't quite relate to videos where people say nothing. I need to hear what is going on.
My 8590L still get the RES BW AMPL FAIL message. I adjusted the BW filters yesterday and now I try this '-37Hz' mode and still the same error :(
I tried the '-2001Hz' and DEFAULT CAL DATA and still the same error...
I know how frustrating these things can be. Mine was out of cal for months before I lucked out and got it going again.
Don't forget to hit PRESET then FREQUENCY then the -37Hz as it seems it is veery picky in how it starts and that short jumper between the SMA and input of the analyzer.
I hope you get it working.
BTW - what does -2001Hz unlock?
Folks, I hope you all are doing well? can this community help me with how to clear error 351 (SETL FLD The YTO error voltage is not settling) on HP 8563E Spectrum analyzer
I am going to guess a power supply issue with some ripple on the power supply voltage? Just a guess. Power supplies are always a good place to start. Best of luck getting your SA repaired...
@@ElPasoTubeAmps Thank you. Very well appreciated
It lost it's mojo battery! LOL