¿ªÔÆÌåÓý

  1. HP-Agilent-Keysight-Equipment
  2. Messages
Expanded Topics Messages
Date
Fitting rack ears to ageing HP equipment

 

I have an HP141T mainframe spectrum analyzer that I would like to rack mount. The manual says to use a thin bladed tool to remove the aluminum trim strips. My HP141T still has these strips in place and after 50 years or more they don't want to come out. I've tried using hot air to loosen them, so far that has not worked. Even getting a chisel in place does not do anything.?
?
Has anybody experienced this challenge and found a simple solution? I thought after all the fixing up work I had done this would be the easy part!
?
Tim K9VB
Re: HP 3586 counter reading high

 

If you are in a 50Hz region, it could be a power supply ripple?
So I would check caps, diodes, etc.
?
Leo
HP 3586 counter reading high

 

¿ªÔÆÌåÓý

My HP 3586's counter reads about 24 Hz high on any input frequency.

The rear panel fx output reads whatever is input to the front panel.

It passes all TF tests with the exception of TF-13 - 3-2 (counter).

I swapped A22 from a parts donor and that fails the test also. ( That A22 could be bad also!)

Any suggestions>

73,

Bill Riches, WA2DVU
Cape May, NJ
3586B Counter problem

 

My HP 3586's counter reads about 24 Hz high on any input frequency.

The rear panel fx output reads whatever is input to the front panel.

It passes all TF tests with the exception of TF-13 - 3-2 (counter).

I swapped A22 from a parts donor and that fails the test also. ( That A22 could be bad also!)

Any suggestions>

73,

Bill Riches, WA2DVU
Cape May, NJ
Re: Troubleshooting a 8591e with opt 130

 

¿ªÔÆÌåÓý

Hi Marco,

?

The diode Macom MA4E1338B1 would be OK, I had also found this equivalent.

There was also TPM2840-03, a little bit more performing than the original diode, but really very close...only 5V protection however.

?

I found a picture showing the section about the first converter of the 8591E which is different from the 8591A.

?

The method I used:

  • I replaced cr1 and cr2
  • I close the lid and I test, I see if the signal to the monitor at 0Hz, is lower than ideally, at the first division (upper left, picture 8591 LO leakage).
  • If the diodes are not matched well enough, the carrier at 0Hz will exceed the first division at the top of the left screen.
  • In such a case, change CR2 only, because easier to replace and redo the test.
  • It may work from the first attempt as in my case, but I had still tried a second attempt out of curiosity, and got slightly better, so I did not continue with further attempts.
  • I successfully closed, tested and calibrated everything because there was no other problem.

?

I will do some tests with the screen capture program controlling the rs-232 port.

?

Yves

?

?

De?: [email protected] <[email protected]> De la part de jansen.marco90 via groups.io
·¡²Ô±¹´Ç²â¨¦?: 10 novembre 2024 04:40
??: [email protected]
Objet?: Re: [HP-Agilent-Keysight-equipment] Troubleshooting a 8591e with opt 130

?

Hi Yves,

?

That's a clear overview, I agree it's better to repair the first converter.

I googled for the diodes for a bit, found the HSMS-2812 to be obsolete. Did find the Macom MA4E1338B1 series to be pretty close on RF specs but it has a breakdown voltage of only 8v compared to the 15v of the HSMS-2812. Not too sure wether that would be a problem though. They aren't sold in matched pairs so i'd have to try to match them myself I guess.

So would be good to know where you got the replacement diodes and which you got.?

?

My SA doesn't have the GPIB port but it does have the serial and parrallel port, I found some other projects online of people making printer/plotter emulators to be able to get screencaptures but none look as good as yours do.

?

I should be able to start fixing the attenuator next week.

?

Marco

?

?

first converter 8591E.png
diode.png
8591 LO leakage.png

Re: 85620A Firmware

 

Hello Guido,
I don't exactly understand what you mean, but does it help if I read out my version 91-01-16 EPROM?
?
Jaap PA0JRK
Netherlands
Re: HP ESG3000A backlight issue revisited....your thoughts please?

 

Hi. Been following with interest. I found the data sheet for the inverter and although I cannot find details about the control voltage, they have this:
which suggests that it is a POSITIVE voltage per the video.
?
So something doesn't make sense here. Did your unit have this inverter? If so, we are looking at the wrong schematic (it's the one I have as well) AND something
is wrong with your CPU board. Did you check this voltage with J19 disconnected?
?
Mark
?
Re: Another dead 8753D YTO

 

That is good news Marcus! You have inspired me to tackle the job myself.?
73,
Matt, KD4PBS
Re: HP ESG3000A backlight issue revisited....your thoughts please?

 

DAC (contrast/brightness) configuration should be the same


On Sun, 10 Nov 2024, 13:27 Dave B via , <davebullockmbe=[email protected]> wrote:
Hi Milan,
Well now I'm confused as my motherboard number is neither of the ones you have quoted :-o
?
?
Dave
?
Re: HP ESG3000A backlight issue revisited....your thoughts please?

 

Hi Milan,
Well now I'm confused as my motherboard number is neither of the ones you have quoted :-o
?
?
Dave
?
Re: HP ESG3000A backlight issue revisited....your thoughts please?

 

error,
Same for pin 1 of U605, 0 to -10V varying the brightness

Virus-free.


On Sun, Nov 10, 2024 at 12:10?PM Milan Vasic <vasa1958@...> wrote:
Dave,
First check your motherboard model:
The E4400-60124 can only use display with Negative contrast (VLDC)
The E4400-60035 can use pos and neg VLDC
I know, its for contrast, but DAC configuration is the same: part A of U604 for brightness, part B for contrast.
Check voltage swing on pin 7 of U605 varying the contrast, should be 0 to -10V.
Same for pin 1 of U604, 0 to -10V varying the brightness.
If this OK, problem is after DAC.
Milan

Virus-free.

On Sun, Nov 10, 2024 at 10:43?AM Dave B via <davebullockmbe=[email protected]> wrote:
Hi Milan,
Thanks, yes I had spotted the DAC is an AD7528 and that it seems to be powered only from +5V suggesting that the output can only be a varying positive voltage?
?
Looking at this simplified block diagram the 'inverting' amplifier following the DAC would then suggest a negative varying voltage at TP601?
This does seem to agree with the voltage I am measuring on my instrument i.e. (minus) 0.24V to (minus) 1.33V. (
Though why such a limited range?)
I have scoured all the 'service' information that I have managed to find on the web, and despite TP601 being a relevant test point to aid fault finding around the DAC area
there are NO "fault finding" flow diagrams or Test point voltage tables to be found anywhere!
It's very frustrating.
If my backlight control voltage is correct (and it now seems to agree with the schematic?) I am still bemused how it controls the CCFL inverter which is powered from +5V, meaning
the control voltage is operating outside the rails of the inverter.
Very intriguing?
Thanks for all your help.
Dave
?
Re: HP ESG3000A backlight issue revisited....your thoughts please?

 

Dave,
First check your motherboard model:
The E4400-60124 can only use display with Negative contrast (VLDC)
The E4400-60035 can use pos and neg VLDC
I know, its for contrast, but DAC configuration is the same: part A of U604 for brightness, part B for contrast.
Check voltage swing on pin 7 of U605 varying the contrast, should be 0 to -10V.
Same for pin 1 of U604, 0 to -10V varying the brightness.
If this OK, problem is after DAC.
Milan

Virus-free.


On Sun, Nov 10, 2024 at 10:43?AM Dave B via <davebullockmbe=[email protected]> wrote:
Hi Milan,
Thanks, yes I had spotted the DAC is an AD7528 and that it seems to be powered only from +5V suggesting that the output can only be a varying positive voltage?
?
Looking at this simplified block diagram the 'inverting' amplifier following the DAC would then suggest a negative varying voltage at TP601?
This does seem to agree with the voltage I am measuring on my instrument i.e. (minus) 0.24V to (minus) 1.33V. (
Though why such a limited range?)
I have scoured all the 'service' information that I have managed to find on the web, and despite TP601 being a relevant test point to aid fault finding around the DAC area
there are NO "fault finding" flow diagrams or Test point voltage tables to be found anywhere!
It's very frustrating.
If my backlight control voltage is correct (and it now seems to agree with the schematic?) I am still bemused how it controls the CCFL inverter which is powered from +5V, meaning
the control voltage is operating outside the rails of the inverter.
Very intriguing?
Thanks for all your help.
Dave
?
Re: HP ESG3000A backlight issue revisited....your thoughts please?

 

Hi Milan,
Thanks, yes I had spotted the DAC is an AD7528 and that it seems to be powered only from +5V suggesting that the output can only be a varying positive voltage?
?
Looking at this simplified block diagram the 'inverting' amplifier following the DAC would then suggest a negative varying voltage at TP601?
This does seem to agree with the voltage I am measuring on my instrument i.e. (minus) 0.24V to (minus) 1.33V. (
Though why such a limited range?)
I have scoured all the 'service' information that I have managed to find on the web, and despite TP601 being a relevant test point to aid fault finding around the DAC area
there are NO "fault finding" flow diagrams or Test point voltage tables to be found anywhere!
It's very frustrating.
If my backlight control voltage is correct (and it now seems to agree with the schematic?) I am still bemused how it controls the CCFL inverter which is powered from +5V, meaning
the control voltage is operating outside the rails of the inverter.
Very intriguing?
Thanks for all your help.
Dave
?
Re: Troubleshooting a 8591e with opt 130

 

Hi Yves,
?
That's a clear overview, I agree it's better to repair the first converter.
I googled for the diodes for a bit, found the HSMS-2812 to be obsolete. Did find the Macom MA4E1338B1 series to be pretty close on RF specs but it has a breakdown voltage of only 8v compared to the 15v of the HSMS-2812. Not too sure wether that would be a problem though. They aren't sold in matched pairs so i'd have to try to match them myself I guess.
So would be good to know where you got the replacement diodes and which you got.?
?
My SA doesn't have the GPIB port but it does have the serial and parrallel port, I found some other projects online of people making printer/plotter emulators to be able to get screencaptures but none look as good as yours do.
?
I should be able to start fixing the attenuator next week.
?
Marco
?
?
Re: HP 16500C Display Question

 

Does anybody know ( maybe in one of the service manuals ) if I could find the pinout of what I think is 40 pin IDC that plugs into the side of the 16500L module. That cable I think it comes off 16500B motherboard. I want to find a pinout for that ( unlikely but hopeful ) ...?


On Sat, Nov 9, 2024 at 8:12?AM Adrian Godwin via <artgodwin=[email protected]> wrote:
I thought I'd seen something on eevblog but didn't find that.
I think that card is another of these programmable devices but for ?20 shipped I'll give it a try. I want to do something like this for a 53310A and it might work there.
?



--
Damien Towning

?
Re: Another dead 8753D YTO

 

Hi all,
?
I'm happy to report that I've successfully running the Wiltron YTO in my HP8753D :-)
?
All thanks to well documented YTO replacements for the HP8753C and the luck that HP8753D have almost identical A11 Loop filter and EYO driver.
?
To get the YIG working I had to utilize the -15V line in pin1 on the EYO connector in the A3 source to make -5V for the Wiltron YTO.
?
I did not change the A11 Q7 transistor, but I put a 2mm thick copper plate under it.
?
And do not forget to run all the adjustments that is necessary after A3 source module change.
?
Before and after pics below.
?
Any questions, just post in this thread and I'll try to answer.
?
Best regards
Marcus, SA5PMG
?
?
?
WTB HP/AG 85032B Cal Kit or N FEM parts

 

WTB HP/AG 85032B Cal Kit or N FEM parts
?
WTB 1 each:
85032-60005 N Load Female
85032-60009 N Short Female?
85032-60012 N Open Female
?
Standards need to be in very good condition, thanks.
Kit Foam in box can be crummy, that's OK
?
Will consider entire 85032B Cal Kit for the right price.
Please reply direct to me with your offers, photos would be great.
Please include shipping to WA 98292.
Thanks very much
Jason Kovatch
Re: HP ESG3000A backlight issue revisited....your thoughts please?

 

DAC is AD7528JP, check the datasheet
Milan

Virus-free.


On Sat, Nov 9, 2024 at 8:39?PM Milan Vasic via <vasa1958=[email protected]> wrote:


On Sat, 9 Nov 2024, 20:14 Dave B via , <davebullockmbe=[email protected]> wrote:
Hi Milan,
Wow that's great to see an actual schematic and a test point, you are a star :-)
Do you have any data for what the voltages should be at that test point TP601?
Presumably when testing the engineer checks TP601 at "backlight off" and Backlight full brightness" and notes the correct control voltage?
?
?
This would be the information that would be key to my getting my new backlight driver interfaced correctly as I seem to have been completely misled.
Thanks for your kind help.
Dave
Re: HP ESG3000A backlight issue revisited....your thoughts please?

 



On Sat, 9 Nov 2024, 20:14 Dave B via , <davebullockmbe=[email protected]> wrote:
Hi Milan,
Wow that's great to see an actual schematic and a test point, you are a star :-)
Do you have any data for what the voltages should be at that test point TP601?
Presumably when testing the engineer checks TP601 at "backlight off" and Backlight full brightness" and notes the correct control voltage?
?
?
This would be the information that would be key to my getting my new backlight driver interfaced correctly as I seem to have been completely misled.
Thanks for your kind help.
Dave
Re: HP ESG3000A backlight issue revisited....your thoughts please?

 

Hi Milan,
Wow that's great to see an actual schematic and a test point, you are a star :-)
Do you have any data for what the voltages should be at that test point TP601?
Presumably when testing the engineer checks TP601 at "backlight off" and Backlight full brightness" and notes the correct control voltage?
?
?
This would be the information that would be key to my getting my new backlight driver interfaced correctly as I seem to have been completely misled.
Thanks for your kind help.
Dave
3661 - 3680 of 151568