Re: HP6209B component location layout
I poked around a bit further and discovered that the +43V reference supply that was reading low at 34.2V actually had 14V of ripple on it. After removing and checking C12 a 450uF 85V cap, it was reading 135nF. Replaced with 470uF 100V cap, and voltage came up to 43.4V. Then did the whole volt and current meter calibration, and the 12mA range was no longer pegging to the left, but now rather indicating about 4mA without any load.
Put a 5K 10T pot in parallel to the existing 30K R38 resistor and was able to zero the 12mA range without affecting the 120mA. The pot was reading 2.7K, which I then replaced with a fixed resistor and now the 12mA scale was almost zeroed, only a hair above zero, so left it there for now. It seems that the circuit really wants about 2.4K in parallel to R53 (30K with the 2.7K from the pot) to properly balance the bias on the 12mA scale, but until I can get the proper resistor did for now leave both the 30K and the newly added 2.7K in place.
Both current ranges now seem accurate (as much as that analog meter will allow). Tested the 120mA with a 2.5K 10W at 250V and meter showed 100mA right on the money, verified with by DMM also in circuit. Then put a 10mA load and the meter on 12mA scale was showing also almost right on the money.
Lesson learned, check the main caps first, you dummy.
Also checked C20 (25uF 475V) at the rear output and it read 26uF with 2.0 ohms ESR. Good enough.
The C14 main supply cap seems to be good as well, kind of a pain to remove and test, so just read the DC and AC voltage across it with DMM while output voltage was set to 320V. The cap had 334.5VDC and 0.477VAC ripple across it. With the output of the power supply still at 320V and no load, there was about 1mV of AC ripple (on the DMM), and with a 100mA load about the same amount of ripple.
I think that it can now be called good to go.
BTW needed to slightly adjust the meter mechanical zero so had to remove it, and then while trying to get it back in place was wondering who came up with that plastic mounting clip scheme. What a pain in the rear to make both sides click back in place.
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Re: HP 85047A test set on 8753A analyzer -- switch control board jumpers to retrofit for opt 009 (mechanical switch)
I believe the control module (rear panel) has one or more abnormalities - I tried setting attenuator (stimulus>power>attenuator 1) and rather than adjusting the attenuator, the test set switched ports or had other abnormal responses depending on the selected attenuator value. This misbehavior occurred regardless of W1 and W2 jumper presence/absence.
Given this, my original posting about setting option 009 is incorrect as the test set is malfunctioning in other ways and will require repair, not just reconfiguration. (I re-routed cable back to my original test set and it continues to work normally, so the issue is in the test set under consideration.)
Dave
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There is some information on the low band module A24 in here starting page 36:
I see now that this is a microcircuit and not repairable.
I suppose, in my low band module the oscillator has drifted over time such that it locks now to the wrong 100MHz harmonic.
A pitty, one would just have to re-tune the oscillator if it was possible.
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Does anybody know where I could obtain a replacement for the broken A24 low band module of my 83651A?
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Tom DG8SAQ
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Re: HP 53310A modulation domain analyzer memory upgrade
Thanks Ozan..!
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Will report back here on the transition from SOJ to DIP for those that may follow...
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Dear friends, I ask you if possible to help me solve my problem: I have SA HP70000 and a HP70820a that worked perfectly.
At a certain point without having used it improperly an error occurred (7301 ch 1 up bus, wr addr: bit).
I ask you if anyone has info or has had the same problem.
I ask for your help in trying to solve it.
Thanks
Gianni
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Re: Tricks and thoughts about the 3457A battery
On 3/31/25 22:12, Martin via groups.io wrote: Or the other way round? Put the instrument on an isolation transformer. I've got nice isolation transformers for sale if anyone needs one. MGE Ultra Isolation 2.4 kVA and smaller.
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Matched JFETs in TO-71, 6-pin packages are pricey.? Need to get a few with characteristics in the ballpark so I pulled a couple from a good meter and measured them.? ? ? ? ? ?
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making 8620C sweeper scales
Hi all, Delurking to note that I took the liberty of uploading some additional files for DIY 8620C sweeper scales to this folder, which is hopefully okay: /g/HP-Agilent-Keysight-equipment/files/All%20HP,%20Agilent%20and%20Keysight%20instruments%20in%20folders%20by%20part%20numbers/8000%20to%208999/8620/8620%20%20%20DIY%20Scales I recently acquired 86240B and 86290B-H08 sweeper plugins, both missing scales. This was annoying enough that I designed a replacement blank scale in OpenSCAD for 3D printing. The STL file prints fine for me with PETG, though I had some warping problems that I think I fixed by adding internal braces. It may also require a lower bed temperature, but if the scale bows, it'll be super obvious. I used LibreCAD to divide the lines, and added the text in OmniGraffle. I've printed a batch of these on Avery UltraDuty HGS Chemical Labels for laser printers, then cut them out using a steel straightedge and utility knife. Printing on plain paper and sticking them on with 3M 77 spray adhesive works just fine, and doesn't require sanding the scale beforehand. YMMV. I've not found photos of the actual 86290B-H08 scales anywhere, so may not have the same major/minor ticks as the originals. Corrections welcome, but hopefully this is useful to someone. Adam KK7ASV
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Re: Repair HP3455A Multimeter
Hi,
yesterday i got the Jfets from digikey, i replaced Q19,Q21,Q4 ,Q22 but the result is the same, still error 10. According to the flowchart the advice is to check Q4,Q19 and components around.
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There are many components around, so could anyone look at this part of the schematics and give an advice?
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May be U3??
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And I have a curious 8.75 V at pin 14 of U5, should be -24V, but not? in focus of cal test 10.? (I replaced already U5,U4,U6)
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Ralf
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Re: Tricks and thoughts about the 3457A battery
Hello Greg,
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I took the option of powering the 3457A in the normal way, with an earth connection as usual. At the same time I floated the soldering iron by powering it from a car battery and a DC-to-AC converter (the type which is commonly used in campers and similar vehicles). Another option is to use line power and an isolation transformer, if you have one. A portable, battery-powered or soldering iron would work just as well.
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Cheers,
Joel
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Re: Tricks and thoughts about the 3457A battery
Hello David,
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What you are suggesting is obviously a good solution. However, it is WAAAAAY above what my "hobby budget" can afford. To make matters worse, Keysight will not do any business with private individuals, at least in Europe. You'd have to find and alternative calibration lab, which would calibrate the meter but would not probably not replace the battery since HP does not document this replacement.
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Cheers,
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Joel
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Re: Tricks and thoughts about the 3457A battery
Hi Razvan,
I used a Radiospares 185-4654 socket, which sells for one Euro or so. It turned out to be a no-brand Chinese import, you can find the same socket on Epay or other sellers. I could not find this type of socket from "premium" brands, like Keystone and others.
By the way, the same type of battery is sold as "ER14250" by some vendors, and is available from some vendors with leads and a 2-pin female connector. You may also want to investigate this type of solution.
Cheers,
Joel
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I'm not sure if you were asking if these meet the spec but I wanted to clarify how your finding verify the earlier numbers (for myself as much as future readers).
I believe the spec of Idss@Vgs0 is 1mA "or greater". The Drain-Source current when fully on (Vgs=0) is a primary characteristic of a JFET. Being able to pass more current than specified is OK. So an IDss of 2.5 or 4.2mA exceeds the minimum specification.
On Tue, Apr 1, 2025, 1:43?AM John Warren via <johnwarren376= [email protected]> wrote: Thank you both for chiming in.??
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The unit is a 7562A, I apologize for the typo.
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I pulled a couple from another board and measured one side of each package, presumption is the other is similar.
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I was tweaking with the settings so some inconsistencies below.? ?The pinch off voltage range based on the two sets is between -1.6V and -2.2V.? IDSS 2.6 to 4.2mA at 10V VDS.
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The following items have been added to the Files area of the [email protected] group.
By: Adam R. Maxwell <amaxwell@...>
Description:
Additional 8620C scales drawn using LibreCAD for 86240B and 86290B option H08. Sized for US Letter paper.
The following items have been added to the Files area of the [email protected] group.
By: Adam R. Maxwell <amaxwell@...>
Description:
STL file for printing custom 8620C scales. Printed using Ender 3 with PETG, and PLA should work as well. Surface may require sanding before sticking/gluing a scale face on.
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Re: Tricks and thoughts about the 3457A battery
If one chooses to try the instrument power-up approach as you had mentioned make certain that you use a soldering iron that is not connected to third wire ground... Or the other way round? Put the instrument on an isolation transformer. cheers Martin
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Re: E5052A Power On Test (3.3V Bus Supply)
Hi all,
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Great thread, lots of useful info including suspected power supply issues on the A3.
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I recently picked up an E5052A at auction. I've worked on similar era Agilent boxes but new to this model.?
Unit was sold has having a known issue on startup. There is a strange startup message which I believe is related to the A3 DSP board:
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This happens on power up. The analyzer will then show the following runtime error and exit; it never makes it to the measurement screen:
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The first few things I did was to backup the original HDD (20 GB Travelstar) and set that aside.?
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I used the ghost factory backup image in the recovery partition to make a new hard drive, which booted just fine.?
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Same error message on power up with original FW version 2.00. Updating to 2.51 does not change anything.
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I'm convinced that the error "m_pA3drv -> Initialize()" is likely a hardware error, telling us that the A3 ADC/DSP board fails to initialize.?
This is only a guess; I see that jmr has disassembled the firmware. Your software skills are far superior to mine; maybe this error message makes more sense to you?
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What I'm working on now is to make a wiring harness so I can extend the 3 x 32 (96 position) header for the A3 ADC/DSP.?
This way I can power the board outside of the chassis and check things like power supply rails, clock distribution for the ADCs and FPGAs.?
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By the way, is the A3 board a huge hassle to remove for anyone else? The board is wedged extremely tight in my unit. I had to use a screwdriver to pry against the metal shield bolted to the board. I did it very carefully so no damage... it was impossible to remove otherwise.?
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Giving the A3 a once over with shield removed, are a few CPLDs and a tssop FLASH chip, probably for the Sharc DSP. Hopefully its not a data corruption issue on one of these factory programmed devices...?
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HP 85047A test set on 8753A analyzer -- switch control board jumpers to retrofit for opt 009 (mechanical switch)
Working on a 85047A test set which needs to be retrofitted with mechanical switch 33311B, as it has dead solid state switch and will be used with 8573A analyzer (pre-dates the 85047A). Goal is to end up with an 85047A opt 009. This issue has to do with interaction of the switch control board (back panel) and the analzyer's port A(1) and B(2) switching controls.
The 8753A analyzer is working normally with an 85046A opt 009 (mechanical switch) which was retrofitted from solid state at some point in the past. The 8753A is on firmware 1.01.
The analyzer has never been tried with an 85047A since I've had it.
The switch control board (along back panel) has three jumpers defined - J3, W1 and W2. J3 is not discussed in the manual but is installed from factory. I've installed 0.025" square (typical wire-wrap style) pins on the back side of the board for J3, W1 and W2 so that they can be reconfigured without pulling the board from the chassis.
As built (with solid state switch)
J3 - present (not mentioned in manual)
W1 - absent
W2 - absent
Behavior - port B selected <1 second during power-up, never again.
As documented (with mechanical switch)
J3 - present (not mentioned in manual)
W1 - absent
W2 - present
Behavior - port B selected <1 second during power-up, never again.
Other experiments
J3 - present (not mentioned in manual)
W1 - present
W2 - absent
Behavior - port B selected ~3 seconds during power-up, never again.
J3 - present (not mentioned in manual)
W1 - present
W2 - present
Behavior - port B selected ~3 seconds during power-up, never again.
So, at this point I cannot get the analyzer to switch to port B (right hand port) when initiating a 1-port S22 calibration.
Any suggestions at this point?
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I was only changing the low band module, because I got one from an other older generator. In the 8360 families, this low band module is the weak part. That's a very complicated part, I was trying to obtain solutions to know better how it is made inside to open and verify it but it seems it's very difficult to have some information. At the present moment, having got at least 7 different generators from this family, I already have in a corner 2 low band modules with problems. That's why I try to collect all generators from this family because we need so many parts to let them alive. That's the most recent family that we can repair and calibrate ourself without help of unobtainium software or hardware. Later products are PSG and nothing is possible without requiring Keysight services. From memory only, it was in beginning of 2018 that I was swapping this module. Once the swap made, the error disappeared, and few months later i already sold the 83630B because having replaced it with a 83640A. In this last one I replaced the VFD screen that was extremely dim. And I currently search to increase also the output power and to add an output attenuator. I don't remember what was the error on the second low band module that I needed to replace too, also for an 83630B.
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Re: HP 53310A modulation domain analyzer memory upgrade
Hi Dave,
I sent you a direct message, please check your inbox.
Ozan
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On Mon, Mar 31, 2025 at 02:43 PM, Dave Wright wrote:
Hi Folks,
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On the hunt for a source for the RAM chips to expand the memory in my 53310A
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The usual Googling around has yet to yield 4 pieces from a single source.
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Do any of you have 4 that you would be willing to part with..?
Candidates are: Cypress CY7C194-25PC, Hitachi HM6708P-25, ?Motorola MCM6208P25, ?or equivalent.
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Located ?Louisville, KY 40206 USA
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Re: PCB CAD used and/or sold by HP ?
In '88 and for a few years later, for the 360 and greater (more powerful), HP sold CAE tools such as DCS (schematic layout), DVI (design verification using GenRad's HILO logic/fault simulator), and PCDS (PCB layout). I used the first two to create test pattern files for circuit board testing on our HP3065AT functional tester. See attached slide re DCS and PCDS interface.
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In addition, a mechanical drawing package called ME10 was available, created at HP Germany, IIRC.
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As (IBM) PC's were becoming more powerful and improving graphics capabilities, and third party tools were improving and targeting the PC market, HP eventually bowed out of the CAE market.
---------- Original Message ---------- From: "alan victor via groups.io" <avictor73@...> To: [email protected]Subject: Re: [HP-Agilent-Keysight-equipment] PCB CAD used and/or sold by HP ? Date: Mon, 31 Mar 2025 06:44:01 -0700
Here is a link to EGS and some history.?
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https://www.hewlettpackardhistory.com/item/a-new-dimension-to-design/
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Ralf Rosche
Martin
Kevin A.
