Re: Agilent E4404B Spectrum Analyzer With Dead PSU Repair
The 310VDC on the bulk caps are present even during the click, dipping only to 295V when click is heard. Measured them and they look fine to. So probably not the problem.
I've just check the primary side actually. Monitoring the 3 ICs (PWM controller, LT 1121 regulator and LM339) supply voltages I found them to fluctuate wildly with the clicking sound (12-18V I believe), causing the entire section of that board (which I assume is the primary side controller) to power on briefly before turning off again. I'm tracing out the controller supply rail right now to see where it leads.
Also I've removed all the X2 RIFA caps, they're for EMI so it's probably ok to not have them for now.
I have not tried to load the 5V std by rail yet, but will keep that in mind.
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Re: Agilent E4404B Spectrum Analyzer With Dead PSU Repair
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On Tue, Apr 23, 2024 at 05:04 AM, hardyhansendk wrote:
Hi
Yes the digital IF in E4406A and MXA? are variable preselected—the 12 bit version are the same ,but less dynamic range!
Hardy
Thanks! Is it possible to find out any history of the MXA analysers from the seller? I would assume that nearly all of these analysers would have been used in ATE racks for the testing of mobile phone related stuff. If so, they could be in very good condition cosmetically. I'm not sure how many hours they will have been running for in the ATE racks but some could have been running 24/7 for quite a while. This probably doesn't matter that much though. It wouldn't put me off buying one if I was looking for a decent 3.6GHz spectrum analyser. At the risk of sounding like a stuck record, I can't emphasise enough just how good these MXA analysers are. ?1500 is a great price, especially if the noise figure drive is fitted to them as standard. Any missing software options can usually be added for free after the purchase. I suspect some of the sellers will have already done this, because it should be easy to generate the licence codes.
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Re: Agilent E4404B Spectrum Analyzer With Dead PSU Repair
The E440* PSU is a less well known topology (CUK) compared to the usual flybacks we see. Probably made sense for the 12V-in capability. I'd be very curious to see a schematic of these, but I don't think an official one exists ?
+1 for replacing RIFAs on sight, although I don't think they're the cause here.
I've rarely found bulk caps to be the problem; while possible, it wouldn't be the first thing I check. Now on a flyback I would look for the (small-ish) "startup cap", an electrolytic on the primary side that serves to power the controller IC. Can't say for sure if the same is applicable on this one, but I would take a close look at any small lytics on the primary side.
You could look at the IC supply rails ( I see a 339 comparator, LT1121 linear (!) regulator, and U6 near an opto but can't read the markings), they will probably be pulsating with the 'click' you're hearing.
*** Don't probe anything on the primary side with a plain oscilloscope !! unless you know exactly why and how not to kill your scope and/or yourself ***
I don't know how this architecture operates, but it's not impossible that the minimum load requirement would be different in AC or DC mode; have you tried connecting something to the 5V standby rail ?
There is some related info here:
https://www.eevblog.com/forum/repair/hpagilentkeysight-e4403b-repair/
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HP85101 Display/Processor searching for PCB's
I have a HP85101A? with 3 modules beyond repair. Perhaps someone has surplus? these modules/PCB's , and is willing to sell/send them ?. I'm looking for: A11 Processor A14 Display A15 I/O Hopefully I can repair this HP85101
2.12.0.0
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Re: 5342A: sometimes counts, sometimes not
Hi,
Yes, the CPU board uses common parts, it is totally repairable. You can actually power up the board outside the unit for easy repair. I had one with faulty ROM, just as I got around using an adapter board to replace it with 2716 EPROMs, I found a replacement CPU board on eBay. I wrote about it on my blog:
Szabolcs
Wilko Bulte via <wkb= [email protected]> ezt írta (id?pont: 2024. ápr. 23., K, 11:14):
The microprocessor board is the lesser of your potential problems. Tricky is that the 3 ROM version of that board uses mask ROMs. There are no pin-equivalent EPROMs for those. I went down a rabbit hole with one of my 5342A, assuming that a ROM was faulty. In the end it wasn't.
Worth checking is the dipswitch on the microprocessor board. It is used to enable signature analysis mode. I found stories from people who had a bad switch, obviously that prevents the firmware from running correctly. I replaced the switch in mine, just because.
Wilko
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Re: Seeking HP 80000 Data Generator (aka 2900A) system software
Hi Brian,
I tried to send you a zip file of the 80000 system software but it was too large. It turns out that the files are available on the KO4BB website (). Just search for "80000" under the "Manuals" tab and you'll find them.
Let me know if you are able to download them. If not, we can figure out a way to get my zip file to you.
Regards,
Stan
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Thank you!
If an option is listed but doesn't have a version, does that mean it is installed but simply isn't a versioned option?
Peter
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On 4/23/2024 1:04 AM, hardyhansendk via groups.io wrote: This ebay seller( fuof6666 ) have the right MXA`s,with the options you like.
Many have bought from them,it’s a big international test equipment reseller--I have no connection with them-just a satisfied customer.
Hardy
-----Oprindelig meddelelse-----
Fra: [email protected] <[email protected]> P? vegne af John Griessen via groups.io
Sendt: 22. april 2024 23:12
Til: [email protected]
Emne: Re: [HP-Agilent-Keysight-equipment] N9020A
On 4/22/24 14:51, Peter Gottlieb wrote:
So what options should I look for in one of these MXA units? I'm not sure yet. I asked from an ebay seller and got out of focus photos:
--
Denne mail er blevet tjekket for vira af AVG-antivirussoftware.
www.avg.com
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Re: 5342A: sometimes counts, sometimes not
The microprocessor board is the lesser of your potential problems. Tricky is that the 3 ROM version of that board uses mask ROMs. There are no pin-equivalent EPROMs for those. I went down a rabbit hole with one of my 5342A, assuming that a ROM was faulty. In the end it wasn't.
Worth checking is the dipswitch on the microprocessor board. It is used to enable signature analysis mode. I found stories from people who had a bad switch, obviously that prevents the firmware from running correctly. I replaced the switch in mine, just because.
Wilko
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Re: Is it worth looking for a R/3*2 Instrument Controller? - Feedback request
Hello Tony,
I just saw after pressing the Send button that I replied to your thread
instead of mine.
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On 22/04/2024 23:58, Tony Goodhew via groups.io wrote: Hey All,
I've always wondered if I should try to acquire one of the R/3*2
Instrument Controllers (332, 362, 382)
If anyone has one, would you be able to provide some feedback on how you
use it and why you keep it? I've always liked the idea of having one in
my rack and I've just started working with the hobbyist license for HT
BASIC so I can get a handle on what using the original HP BASIC would be
like but I'm just wondering if it is worth trying to acquire and piece
together one of these seeing that the ones I can find today are all
broken or missing things like keyboards etc or if I should just give it
a pass and keep working on HT BASIC for Windows.
Would love to hear your thoughts.
TonyG
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Re: Is it worth looking for a R/3*2 Instrument Controller? - Feedback request
Hello all,
Thanks everyone, very interesting the replies and I will put one of
these R/3*2 models on the wish list.
While researching these HP 9000 series I saw that some Logic Analyzers
from that era look pretty similar to the R/3*2.
For example the 16500A. These can be found much easier and cost much
less than a R/3*2 model.
I don't need the Logic Analyzer function and I can remove all boards to
save on power, just keep the motherboard and use it as a simple
workstation. It has the HP-HIL port for keyboard in the front and also
color display. Rack mount ears I guess are the standard ones as other HP
test equipment.
Would that be feasible to repurpose the 16500A ? Maybe it will need some
new EEPROM/EPROM to match some other Series 300 unit?
If someone has some photos with the 16500A motherboard maybe we can
identify if it matches other 300 series motherboard.
It's just an idea, not sure if this will work...
Regards,
Razvan
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Show quoted text
On 22/04/2024 23:58, Tony Goodhew via groups.io wrote: Hey All,
I've always wondered if I should try to acquire one of the R/3*2
Instrument Controllers (332, 362, 382)
If anyone has one, would you be able to provide some feedback on how you
use it and why you keep it? I've always liked the idea of having one in
my rack and I've just started working with the hobbyist license for HT
BASIC so I can get a handle on what using the original HP BASIC would be
like but I'm just wondering if it is worth trying to acquire and piece
together one of these seeing that the ones I can find today are all
broken or missing things like keyboards etc or if I should just give it
a pass and keep working on HT BASIC for Windows.
Would love to hear your thoughts.
TonyG
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Thanks Hardy, I've ordered a couple of Agilent PSU's from that seller.
Reasonably prices I think.
Appreciate all your help and assistance in this thread as I'm sure others do too!
Best Regards
JohnB
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Re: HP 8568A YTO UNLOCK repair
A9 and A10 working just fine, definitely YTO related now.
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This ebay seller( fuof6666 ) have the right MXA`s,with the options you like. Many have bought from them,it’s a big international test equipment reseller--I have no connection with them-just a satisfied customer. Hardy -----Oprindelig meddelelse----- Fra: [email protected] < [email protected]> P? vegne af John Griessen via groups.io Sendt: 22. april 2024 23:12 Til: [email protected]Emne: Re: [HP-Agilent-Keysight-equipment] N9020A On 4/22/24 14:51, Peter Gottlieb wrote: So what options should I look for in one of these MXA units? I'm not sure yet. I asked from an ebay seller and got out of focus photos: -- Denne mail er blevet tjekket for vira af AVG-antivirussoftware. www.avg.com
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Re: Agilent E4404B Spectrum Analyzer With Dead PSU Repair
Hi Nick,
First I would check after removing the old RIFA is the reservoir capacitor for the switching regulator. It is not uncommon problem that these go low in capacitance, and stops the psu from starting.
Regards, Askild
On Mon, Apr 22, 2024 at 8:55?PM Nick Stanley via <rosewardxiii= [email protected]> wrote: Hi all, figure a good old repair attempt would be a good 1st post.
I bought a broken E4404B SA in hopes to repair it. The seller said it has a dead PSU, but doesn't know if it has any other failures.
I took the PSU out to test it. I decided to test all the MOSFETs and the 2 optocouplers, all tested good.
Then I realized since this PSU can take DC input, I can just supply 12VDC and see if the DC-DC converter secondary side work. And it DOES. All voltage rails (+28V, +15V. +5V. -5V, -15V, fan) are all present. Draws about 5-6W which seems alright.
Which narrows down the failure to the AC mains sides. I checked the mains side, the 2 bulk caps hold a total of about 310VDC, which matches with the peak of rectified mains AC.
When I force the supply on while connect to mains, I hears a small click every second. Measurements of the DC rails shows them varying greatly. It's like the PSU is trying to start up but can't.
Will update with any progress and pictures soon.
Also, as I was testing the PSU, one of the RIFA caps exploded, filling my room with smoke and cover the PCB in tars. Horrible
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Re: Scan From 1404A Amplifier Manual
I took a look at the power supplies of my HP ‘scopes from this era. They all use one of them as the reference for the others, as you have discovered. I think it was my 132A dual-beam oscilloscope that burned up an externally-mounted (not on the PC board) power resistor in a regulator. It was not a failure I would have expected and, of course, I didn’t have an exact replacement, but was able to put two smaller resistors in series to get the power supply working again. I never did learn why the resistor failed, and the problem has not recurred.? Jeremy Nichols
707-529-2639
Jeremy,
No problem.? I'm just glad to hear from you.? I was getting worried...?
Unfortunately, while trying to track down where the noise starts and probing around on the A9 board, I must've shorted the -12.6V rail and, apparently the safeguards didn't guard it.? I found the problems and have it running again (as you might've seen) but now I'm back to it.
Thanks for checking that.? I figured it wasn't something that would be there in a properly-functioning model and that confirms it.
Thanks again, Barry - N4BUQ
From: "Jeremy Nichols" <jn6wfo@...>
To: "HP-Agilent-Keysight-equipment" <[email protected]>
Sent: Monday, April 22, 2024 9:57:38 PM
Subject: Re: [HP-Agilent-Keysight-equipment] Scan From 1404A Amplifier Manual
Barry,
Finally getting back to you on the Chop circuit. Using my 140B’s internal calibrator as a source for both channels of the 1402A, I don’t see any difference in beam width or intensity between Chop and Alt.?
Sorry I can’t?be more helpful.? Jeremy Nichols
707-529-2639
Jeremy, The reason I'm looking into those waveforms is that when I switch the amplifier to CHOP mode, the traces become a bit "fat".? It appears there's some sort of high-frequency noise that's causing the traces to appear fatter in the negative direction - i.e. the trace is there but there's a wider "shadow" on the negative side of the trace.? I was thinking it was probably the chop multi-vibrator getting into the power rails and that still might be it; however, I'm also wondering if the blanking between the chopping action might not be working properly which could cause that ghosting effect. If I recall, the scope you obtained recently is configured just like mine with a 1421A time-base and a 1404A vertical amplifier.? If so, if you select at least two channels and select CHOP mode, do your traces change - especially do they become fatter?? I'm thinking they probably do not and there's something wrong with my scope/plugin but I'm curious to find out whether you see that same behavior and, if so, it could be an anomaly of these scopes (doubtful). Thanks, Barry - N4BUQ I have that manual. Let me check.
Would anyone have the manual for the 1404A 4-channel amplifier plugin?? I would like to see what the waveforms in Fig. 8-25 (Ring Counter Measurement Conditions and Waveforms) look like.? The online versions are pretty poor images and I can't really tell if what I'm seeing - particularly for #4 - are what they should be and a decent picture would really help.
Thanks,
Barry - N4BUQ
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I'll try that tomorrow at work.? Thanks, Hardy!? ? ? ? Jim
Sent from my T-Mobile 4G LTE Device
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-------- Original message -------- From: "hardyhansendk via groups.io" <hardyhansen@...> Date: 4/22/24 9:06 PM (GMT-08:00) Subject: Re: [HP-Agilent-Keysight-equipment] N9020A
This auto cal can be switched off. Hardy ? ? Yeah, the PXAs we have at work take a long time to come up, and they always seem to be doing realignments right when you want to make a measurement!? Another irritating thing is that if I don't power up the PXA on the bench, our test software takes several long minutes to figure out that the PXA is not on the GPIB.? For whatever reason, that's not the case for the PNA-X; the S/W figures it out almost immediately.? Not that the PNA-X (and especially the e-cal box) don't take half an eternity to boot up or warm up.... ------ Original Message ------ Date 4/22/2024 7:26:03 PM Subject Re: [HP-Agilent-Keysight-equipment] N9020A The phase noise of the E4406A is quite good but there's a lot of high performance options for measuring phase noise these days...? it's hard to keep up with it all. For many years I've wanted an Agilent E5052A SSA as used at my place of work. However, I may end up buying one of the modern alternatives for a fraction of the price!?
If you watch an E4406A or a PSA when they are booting, you can see it testing the IF preselector filters. It will say something like aligning LC Prefilter Wide, LC Prefilter Narrow, XTAL Prefilter Wide, XTAL Prefilter Narrow. I've not used a 12 bit E4406A but I assume it will still have these preselector filters.
The MXA will have them as well and it will probably flash up on screen messages when aligning or testing them.?
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This auto cal can be switched off. Hardy ? ? Yeah, the PXAs we have at work take a long time to come up, and they always seem to be doing realignments right when you want to make a measurement!? Another irritating thing is that if I don't power up the PXA on the bench, our test software takes several long minutes to figure out that the PXA is not on the GPIB.? For whatever reason, that's not the case for the PNA-X; the S/W figures it out almost immediately.? Not that the PNA-X (and especially the e-cal box) don't take half an eternity to boot up or warm up....
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------ Original Message ------Date 4/22/2024 7:26:03 PM Subject Re: [HP-Agilent-Keysight-equipment] N9020A The phase noise of the E4406A is quite good but there's a lot of high performance options for measuring phase noise these days...? it's hard to keep up with it all. For many years I've wanted an Agilent E5052A SSA as used at my place of work. However, I may end up buying one of the modern alternatives for a fraction of the price!?
If you watch an E4406A or a PSA when they are booting, you can see it testing the IF preselector filters. It will say something like aligning LC Prefilter Wide, LC Prefilter Narrow, XTAL Prefilter Wide, XTAL Prefilter Narrow. I've not used a 12 bit E4406A but I assume it will still have these preselector filters.
The MXA will have them as well and it will probably flash up on screen messages when aligning or testing them.?
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Hi Yes the digital IF in E4406A and MXA? are variable preselected—the 12 bit version are the same ,but less dynamic range! Hardy ? ? The phase noise of the E4406A is quite good but there's a lot of high performance options for measuring phase noise these days...? it's hard to keep up with it all. For many years I've wanted an Agilent E5052A SSA as used at my place of work. However, I may end up buying one of the modern alternatives for a fraction of the price!?
If you watch an E4406A or a PSA when they are booting, you can see it testing the IF preselector filters. It will say something like aligning LC Prefilter Wide, LC Prefilter Narrow, XTAL Prefilter Wide, XTAL Prefilter Narrow. I've not used a 12 bit E4406A but I assume it will still have these preselector filters.
The MXA will have them as well and it will probably flash up on screen messages when aligning or testing them.?
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Re: 5342A: sometimes counts, sometimes not
Hope that the microprocessor board is not fault, nor the U1 sampler, which is made of unobtainium. I will check synths and loops today...
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fenugrec
Jeremy Nichols
RubenRubio