¿ªÔÆÌåÓý

Date

Re: HP 339A Distortion meter problem

 

CLA freq and trims.

Check osc ampl control Optocouplers or lamp.

J


HP 339A Distortion meter problem

 

My HP339A has some problems:
?
The distortion meter part works , the oscillator works too, but the sinusoidal output has a little oscillation in amplitude only on some frequencies.
?
For example if i set the frequency of the oscillator ai 1 KHZ
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setting 1 - 0 - 1K = 1khz i have a little oscillation in the signal amplitude (some millivolt)
setting 10 - 0 - 100 = 1khz the signal is perfect.
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the oscillation is so low that i can barely see it on the oscilloscope, but is sufficient to make the distortion measurement of the internal oscillator less than 88db in the first setting (and with the needle of the istrument oscillating) . In the second setting the distortion measured is normal and less than 95 db.
?
i think the problem is related to the 1k position of the third frequency knob setting.
?
?


Re: Connector identification

 

This looks pretty much as the bigger (precursor?) of something that evolved into the Hirose U.FL series or I-PEX MHF series connectors.
It is particular that you have what seems the reverse mating of what is 'standard' since more recent days.
?
You could replace both the PCB side and the cable connector with something newer and more readily available.
?
It is unclear what connector on the HP 53131A exactly you are writing about. If my memory serves me right on the HP 53131A the optional timebase is connected through a ribbon cable. Also the optional 3rd input module is connected with another ribbon cable. Could you share more details about that board please?


Re: HP85102C documentation

 

Yes apparently HP made over the year an improvement of this PLL sensitivity also using more modern components.?
So this patent gives a direction, now the real circuit diagram. When I find the latest circuit diagram, I intend to make a PCB which replaces the old.


Updated documentation for 44421A relay card

 

I am seeking updated documentation for a 44421A relay card as used in a 3497A data acquisition system.
?
The latest documentation version I have been able to source is the? 3497A Service Manual 03497-90022 dated 1984. However, my examples of this relay card appear to have been built late 1988 and differ considerably from the 1984 documentation, particularly relating to the number and location of the board configuration links. The PCB number for my examples is 03497-66553 Rev. A
?
If anyone can supply an updated manual or even an updated schematic for this relay card it would be much appreciated.
?
?


08673-67016 Preamp Modulator

 

In my HP8673B the Preamp Modulator module 08673-67016 has an intermediate contact inside.?
Has anyone such a spare module from a dismantled HP8673B ?
Did anyone opened (de-solder the lid) it, and successfully repair it ?


Re: Troubleshooting a 8591e with opt 130

 

¿ªÔÆÌåÓý

Marco

?

For the moment everything seems fine, for the diodes you have to wait so as not to work for nothing.

If they are not damaged, it would be perfect, but given the state of your input attenuator, it would be a stroke of luck.

When you have tried a CAL FREQ+MAG, and you still have 15dB too much, send me the calibration constants.

?

CAL

MORE

MORE

SERVICE DIAG

DISPLAY CAL DATA

?

Also check if the flatness data is at 0dB.

CAL

MORE

MORE

SERVICE CAL

FLATNESS DATA

EDIT FLATNESS

?

Yves

De?: [email protected] <[email protected]> De la part de jansen.marco90 via groups.io
·¡²Ô±¹´Ç²â¨¦?: 19 novembre 2024 02:29
??: [email protected]
Objet?: Re: [HP-Agilent-Keysight-equipment] Troubleshooting a 8591e with opt 130

?

Yves,

?

That's good to know. I can check with MKR CNT On aswell this evening.?

The mixer diodes are still untouched.?

It's still the same 8591e, though a bit of a workaround, it shows CORR indeed but I only did the Frequency Cal. This was to improve the bandpass adjustment. No amplitude cal has been done. Indeed now the levels look pretty good.?

I'll also do another Ampt cal this evening and check the result.?

Perhaps the bandpass adjustment helps? I'm expecting the levels still to be ~15dB too high again after ampt cal though but will double check.?

?

Marco

?


Re: N8973A Firmware Update issue

 

Hello Olaf,
We already had this issue. The better is to prepare the disks using a PC XP based with an internal FDD, external will work also but it's random...
Br.
Antoine


Re: Troubleshooting a 8591e with opt 130

 

Yves,
?
That's good to know. I can check with MKR CNT On aswell this evening.?
The mixer diodes are still untouched.?
It's still the same 8591e, though a bit of a workaround, it shows CORR indeed but I only did the Frequency Cal. This was to improve the bandpass adjustment. No amplitude cal has been done. Indeed now the levels look pretty good.?
I'll also do another Ampt cal this evening and check the result.?
Perhaps the bandpass adjustment helps? I'm expecting the levels still to be ~15dB too high again after ampt cal though but will double check.?
?
Marco
?


Re: Troubleshooting a 8591e with opt 130

 

¿ªÔÆÌåÓý

Marco,

?

OK, I didn't know that Spectrum was full span. So 1800MHz/400points = 4.5MHz, but it's rounded to an integer value. If the marker moves from one point to another, there will be 4 to 5 MHz between the points.

?

For a span of 10MHz, it's 25kHz.

?

But if you activate the frequency counter, then it will be different: MKR CNT ON.

?

So, everything is normal for now.

?

If you look at 0Hz, the amplitude is about -12dBm... I would say not to touch the mixer diodes, unless you have already done so, and that is the final result.

?

I see that the CORR mode is activated, and that the carrier at 300 MHz seems 2 dB too high... before you had 15 dB before.

?

Am I wrong, it seems to be much better with this 8591E.

?

Yves




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Re: HP 1980B

 

Hi Brad

I did a lot of work on the 1980B.? See?
A bit of a pig to work on, but an interesting bit of history.

Regards Steve

On Friday, November 15, 2024 at 04:11:47 AM GMT, Brad Jackson <brad@...> wrote:


  • Country: us
? on: Today at 04:09:39 am ?
Anyone have a good deal of experience fixing an HP 1980B Oscilloscope?

I¡¯ve just got one and it worked for 5 seconds after I got it then the screen and buttons faded out. I replaced all the defective caps in the unit and still no go on the screen.

I¡¯m able to manually adjust the LED¡¯s by inserting a voltage into the base of the front panel character transistor so I know they CAN work but at the moment not under their own strength.

The LED¡¯s get bright when I remove the module from the front of the unit. I have no control over the RPG control. When it boots up almost all of the LED¡¯s light up so it appears as if the front panel is not talking to the microcontroller.

I have a spare unit coming from eBay next week, but it¡¯s a little frustrating when you see that item that you just purchase work very briefly. I know that it can work. More than likely, some little component died while it was turned on.

I should mention that all test points for voltages are spot on. Also I reseated and cleaned every DIP package IC with deoxit.

Also, because I was able to adjust the LED brightness by manually adjusting the control voltage, it makes me wonder if the CRT is working perfectly fine. It¡¯s just that the control voltage that is just the car and Trace intensity be turned off?


Re: Troubleshooting a 8591e with opt 130

 

Yves,?
?
I actually have a picture from before bandpass alignment:
and after alignment:
?
both at 4.5MHz, both at full span though, could that be a resolution error?
I turned on the instrument this morning for a minute, so this is without proper warmup, also connected cal signal:
10MHz span, it sees the peak at 75kHz
?
This evening I'll have some time again to check after proper warmup, see if it shifts.
?
Marco


Re: Troubleshooting a 8591e with opt 130

 

¿ªÔÆÌåÓý

Hi Marco,

?

Your filter is indeed well aligned now. And the ripple in a 6MHz range will be less than 1dB.

?

The fact that the 0Hz peak is at 4.5MHz is really very strange.

The 0 Hz is mainly related to LO-RF leakage, or mixer balance.

If you have -11.5 dBm, I would say wait before changing the diodes, but find the cause why the 0Hz is shifted to 4.5MHz.

The DC offset caused by the mixer will always be 0Hz.

So, if one of the PLLs is incorrect, you will have a frequency shift.

?

For example:

Here is a simulation of this problem with my 8591A.

I replaced the 600 MHz source to the second converter, with my E4432B generator.

The frequency of 600 MHz being multiplied by 3 to give 1800 MHz, an error of 1.5 MHz at 600 MHz, would give me an offset of 4.5 MHz...as shown in the image below. I set my generator to 600 MHz precisely and the center frequency of the 8591 is at 0 Hz. I set my generator to 601.5 MHz and I get an offset of 4.5 MHz.

?

But if the external 10 MHz reference is disconnected, the offset would not be large enough to move 4.5 MHz, there could be up to 10 kHz or so, not counting the REF UNLOCK error message, so it would have to be the first LO¡­counterlock problem? It¡¯s possible to measure first LO at J5 first converter.

?

Send me a picture of this offset from 0 Hz to 4.5 MHz with and without CAL CORRECT.

?

Yves

?

?

Your 8591E

?


Re: HP85102C documentation

 

?
No, I haven't seen them. However I'm interested too.?
?
I have *3* HP85102c that fail A20 self test.?
The PCB card serial number have evolved and I think you listed the later versions.
?
Maybe they are buried in the 1000 page patents.? There's a little in a quick search.
?
?
?


Re: Connector identification

 

Hi Gary,
I did quite a bit search before posting, couldn't find anything similar (perhaps used the wrong keywords) at Digikey, Mouser, Hirose, I-Pex, or Google search for miniature coax connectors.?
?
I was hoping it is a common connector and easily recognizable by someone who used such connectors. It is used on motherboard of HP53131A (stuffed when HS timebase option is used) and HS timebase boards.?
Ozan
?
?
?
On Mon, Nov 18, 2024 at 07:25 PM, Gary Hitchner wrote:

It was suggested it may be a reverse.? There are variations of these small SM connectors, you may have to general search other than DK to find the correct connector.

When we used them on a project we did find SMA adapters and small test cables to SMA, etc.

?

Gary

WA2OMY

From: [email protected] <[email protected]> On Behalf Of Ozan
Sent: Monday, November 18, 2024 9:35 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] Connector identification

?

Hi Gary,

Thank you for the reply. U.fl connectors I can find at Digikey has 2mm diameter like this one:

Also in U.fl connectors cable side seems to slide over the PCB connector outer ring. In this HP connector cable side slides inside the outer ring of the SMD connector.?

?

Ozan

?

?

?

On Mon, Nov 18, 2024 at 06:18 PM, Gary Hitchner wrote:

Yes, I think it¡¯s a U.Fl, used on many GPS receive engines, there are variations, but I think 2.4 MM was common.

?

You can get adapters and cables for these if necessary.? Don¡¯t mate de-mate often, not very robust, can damage easily.

Gary

WA2OMT

?

From: [email protected] <[email protected]> On Behalf Of Ozan
Sent: Monday, November 18, 2024 8:36 PM
To: [email protected]
Subject: [HP-Agilent-Keysight-equipment] Connector identification

?

Hello,

Does anyone recognize what kind of a connector is J2? I also attached picture of the cable it mates to. This connector is on an HP 53131A HS oven option so somewhat relevant to the group. The dimensions are within ~ +/-0.1mm.?

Thanks,

Ozan

?

?

?


Re: Connector identification

 

¿ªÔÆÌåÓý

It was suggested it may be a reverse.? There are variations of these small SM connectors, you may have to general search other than DK to find the correct connector.

When we used them on a project we did find SMA adapters and small test cables to SMA, etc.

?

Gary

WA2OMY

From: [email protected] <[email protected]> On Behalf Of Ozan
Sent: Monday, November 18, 2024 9:35 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] Connector identification

?

Hi Gary,

Thank you for the reply. U.fl connectors I can find at Digikey has 2mm diameter like this one:

Also in U.fl connectors cable side seems to slide over the PCB connector outer ring. In this HP connector cable side slides inside the outer ring of the SMD connector.?

?

Ozan

?

?

?

On Mon, Nov 18, 2024 at 06:18 PM, Gary Hitchner wrote:

Yes, I think it¡¯s a U.Fl, used on many GPS receive engines, there are variations, but I think 2.4 MM was common.

?

You can get adapters and cables for these if necessary.? Don¡¯t mate de-mate often, not very robust, can damage easily.

Gary

WA2OMT

?

From: [email protected] <[email protected]> On Behalf Of Ozan
Sent: Monday, November 18, 2024 8:36 PM
To: [email protected]
Subject: [HP-Agilent-Keysight-equipment] Connector identification

?

Hello,

Does anyone recognize what kind of a connector is J2? I also attached picture of the cable it mates to. This connector is on an HP 53131A HS oven option so somewhat relevant to the group. The dimensions are within ~ +/-0.1mm.?

Thanks,

Ozan

?

?


Re: Connector identification

 

Hi Gary,
Thank you for the reply. U.fl connectors I can find at Digikey has 2mm diameter like this one:
Also in U.fl connectors cable side seems to slide over the PCB connector outer ring. In this HP connector cable side slides inside the outer ring of the SMD connector.?
?
Ozan
?
?
?
On Mon, Nov 18, 2024 at 06:18 PM, Gary Hitchner wrote:

Yes, I think it¡¯s a U.Fl, used on many GPS receive engines, there are variations, but I think 2.4 MM was common.

?

You can get adapters and cables for these if necessary.? Don¡¯t mate de-mate often, not very robust, can damage easily.

Gary

WA2OMT

?

From: [email protected] <[email protected]> On Behalf Of Ozan
Sent: Monday, November 18, 2024 8:36 PM
To: [email protected]
Subject: [HP-Agilent-Keysight-equipment] Connector identification

?

Hello,

Does anyone recognize what kind of a connector is J2? I also attached picture of the cable it mates to. This connector is on an HP 53131A HS oven option so somewhat relevant to the group. The dimensions are within ~ +/-0.1mm.?

Thanks,

Ozan

?

?


Re: Connector identification

 

This looks like the polarity is reversed from "normal" U.fl, though.

But you're right about the lack of robustness; the last U.fl connectors that I (hated to) design into a board were rated for 10 (yes ten) mating cycles.

-Dave

On 11/18/24 21:17, Gary Hitchner via groups.io wrote:
Yes, I think it¡¯s a U.Fl, used on many GPS receive engines, there are variations, but I think 2.4 MM was common.
You can get adapters and cables for these if necessary.? Don¡¯t mate de-mate often, not very robust, can damage easily.
Gary
WA2OMT
*From:*[email protected] <[email protected]> *On Behalf Of *Ozan
*Sent:* Monday, November 18, 2024 8:36 PM
*To:* [email protected]
*Subject:* [HP-Agilent-Keysight-equipment] Connector identification
Hello,
Does anyone recognize what kind of a connector is J2? I also attached picture of the cable it mates to. This connector is on an HP 53131A HS oven option so somewhat relevant to the group. The dimensions are within ~ +/-0.1mm.
Thanks,
Ozan
--
Dave McGuire, AK4HZ
New Kensington, PA


Re: Connector identification

 

¿ªÔÆÌåÓý

Yes, I think it¡¯s a U.Fl, used on many GPS receive engines, there are variations, but I think 2.4 MM was common.

?

You can get adapters and cables for these if necessary.? Don¡¯t mate de-mate often, not very robust, can damage easily.

Gary

WA2OMT

?

From: [email protected] <[email protected]> On Behalf Of Ozan
Sent: Monday, November 18, 2024 8:36 PM
To: [email protected]
Subject: [HP-Agilent-Keysight-equipment] Connector identification

?

Hello,

Does anyone recognize what kind of a connector is J2? I also attached picture of the cable it mates to. This connector is on an HP 53131A HS oven option so somewhat relevant to the group. The dimensions are within ~ +/-0.1mm.?

Thanks,

Ozan

?


Connector identification

 

Hello,
Does anyone recognize what kind of a connector is J2? I also attached picture of the cable it mates to. This connector is on an HP 53131A HS oven option so somewhat relevant to the group. The dimensions are within ~ +/-0.1mm.?
Thanks,
Ozan
?