HP 1980 Digital Scope with HP 1965 Freq Counter
I just re aligned my HP 1980 Digital scope (from 1985, rumored to be First Digital Scope)
Things went pretty well. Everything appears to work.
But I am having trouble with the 1965 freq counter.
I have the service manual for the 1980 but not the 1965 plug in.
It works on the lower resolution settings just fine, but the highest resolution, which is one sec time interval, is KHz high and very jittery.
This thing has a 10 MHz OSC in it
There is also a setting in the menu for a ONE HERTZ OSC for the time (a 24 hr clock and date, which work OK)
I have a sneaking suspicion this is what is used for the one sec resolution. It is a square wave. I cannot find the adjustment for it and do not have the schematics or manual.
Anybody know anything about this?
The 1965 does rise time and phase shift along with some other stuff. This stuff appears to work. Rise time is 33.5 nSec with a 10 MHz sine wave.
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I thought the 8640A had an analog dial and the 8640B only had digital counters.
Thanks,
Barry - N4BUQ
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----- Original Message ----- From: "Jean-Paul" <jonpaul@...>
To: "HP-Agilent-Keysight-equipment" <[email protected]>
Sent: Saturday, January 22, 2022 3:40:36 AM
Subject: Re: [HP-Agilent-Keysight-equipment] 8640B Counter Bonjour, we have 3 of the classics 8640B, never seen that.
Electrolytics that reform are mainly on high voltage valve/tube equipment, not
in solid state.
Any component can have this behavior, unstable till warmup.
However any tantalum bypass caps can have that behavior.
Freeze mist spray is great to diagnose thermally sensitive issues.
The counter was an option and many units had analog dials.
Thus the counter boards are never seen but a "junker" parts donor might have a
good counter board. Doubt if its worth the effort to find one
Clews....look for discolored tant caps or other parts.
a/ Check power on +5 and elsewhere
b/ connectors or PCB card edge ... corroded or oxidized? Exercise , apply
connector cleaner.
c/ socketed ICs on the counter ....poor contact on the sockets.
d/ counter ICs
Bon chance!
Jon
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It looks like a radar retro-reflector. The spheres could be a graded dielectric to act as a luneberg lens retroreflector. Was there any aluminum foil around the inside, maybe on 1/2?
?
I had a truckload of replacement drone aircraft nosecones at one time that sort of looked like this when you split them open: Made like this with a sulfur ball (hi Er, so good for a lens). They were replacements for nosecones that got shot off during live fire target runs....
They got sold off to a company that does movie props....
73
Jeff
In a message dated 1/22/2022 9:20:49 AM Eastern Standard Time, bunge.pjp@... writes:
?
What do you think this is?
It is stacked spheres made of something that sounds like ceramic when tapped with a fingernail.
Looks like but is not Styrofoam.
Heavier than dense Styrofoam, lighter than ceramic.
The case is thin plastic and may be lined in aluminum foil???
The biggest sphere is 12 inch OD and the smallest is 7¡± OD (6.25¡± ID)
All are 3/8¡± thickness.
Close fitting and accurately cast.
Perfectly round despite the camera distortion.
?
Inside are some plastic spheres. The bigger ones are joined in pairs by a metal 8-32 stud. The smaller ones are a different material.
I suspect the bigger spheres in pairs do not belong and I¡¯m not even sure of the small ones.
?
It could be for calibrating RF devices
It could be for calibrating radiation devices, maybe neutron calibration.
Alpha would not pass through, Gamma would not be attenuated.
Beta particles are a possibility but unlikely. I don¡¯t know what the material is.
Regards, Peter
   
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What do you think this is?
It is stacked spheres made of something that sounds like ceramic when tapped with a fingernail.
Looks like but is not Styrofoam.
Heavier than dense Styrofoam, lighter than ceramic.
The case is thin plastic and may be lined in aluminum foil???
The biggest sphere is 12 inch OD and the smallest is 7¡± OD (6.25¡± ID)
All are 3/8¡± thickness.
Close fitting and accurately cast.
Perfectly round despite the camera distortion.
?
Inside are some plastic spheres. The bigger ones are joined in pairs by a metal 8-32 stud. The smaller ones are a different material.
I suspect the bigger spheres in pairs do not belong and I¡¯m not even sure of the small ones.
?
It could be for calibrating RF devices
It could be for calibrating radiation devices, maybe neutron calibration.
Alpha would not pass through, Gamma would not be attenuated.
Beta particles are a possibility but unlikely. I don¡¯t know what the material is.
Regards, Peter
   
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Re: New member (with a dso-x 3012a not booting), Summary - Fixed
Thanks Tommy for the quote but I did what everyone in this nice group of great enthusiasts would do.
For Glen Slick:
In Italy, relations with Keysight are out of the question.
You must not only be a company but an "electronics company",
and other complicated payment rules.
High minimum billable.
Long waits to know if a spare part is really available or not.
Pity it's so.
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Bonjour, we have 3 of the classics 8640B, never seen that.
Electrolytics that reform are mainly on high voltage valve/tube equipment, not in solid state.
Any component can have this behavior, unstable till warmup.
However any tantalum bypass caps can have that behavior.
Freeze mist spray is great to diagnose thermally sensitive issues.
The counter was an option and many units had analog dials.
Thus the counter boards are never seen but a "junker" parts donor might have a good counter board. Doubt if its worth the effort to find one
Clews....look for discolored tant caps or other parts.
a/ Check power on +5 and elsewhere
b/ connectors or PCB card edge ... corroded or oxidized? Exercise , apply connector cleaner.
c/ socketed ICs on the counter ....poor contact on the sockets.
d/ counter ICs
Bon chance!
Jon
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Re: Thermal image database for equipment ?
If anything like this exists, it'll likely be a functionality / addon
to Flex Board View (FlexBV)
Paul Daniels (the author) likes using thermal cameras (as you can see
on that page), so he might be interested in implementing something
like this.
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On Fri, Jan 21, 2022 at 6:48 AM Tim Tuck <timt@...> wrote:
Hi all,
I was having a discussion with a technician repairing some old equipment
and he had taken IR pics with his FLIR to identify hot-spots.
His wish was that there should be a database of IR pics for know good
equipment to compare against.
A quick search of the net didn't turn up anything beyond db's of IR for
training AI mostly for security cameras.
Does such a database exist ?
If not, would creating such a database, that could be contributed to by
all, be a worthwhile endeavour ?
comments ? thoughts ?
thanks
Tm
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Re: Thermal image database for equipment ?
On 1/21/22 10:51 PM, Francesco Ledda via groups.io wrote: I did use a low cost IR camera as a troubleshooting aid to repair complex military equipment, and it was a great help.
I compared working electronic packs with failed ones, and saved me lots of time. Yes, me too, I use one all the time. It is very handy for repairs, and "initial bring-ups". -Dave -- Dave McGuire, AK4HZ New Kensington, PA
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Re: Thermal image database for equipment ?
I did use a low cost IR camera as a troubleshooting aid to repair complex military equipment, and it was a great help.
I compared working electronic packs with failed ones, and saved me lots of time.
Best, Francesco K5URG
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On Jan 21, 2022, at 21:21, Dave McGuire <mcguire@...> wrote:
?On 1/21/22 12:47 AM, Tim Tuck wrote:
I was having a discussion with a technician repairing some old equipment and he had taken IR pics with his FLIR to identify hot-spots.
His wish was that there should be a database of IR pics for know good equipment to compare against.
A quick search of the net didn't turn up anything beyond db's of IR for training AI mostly for security cameras.
Does such a database exist ?
If not, would creating such a database, that could be contributed to by all, be a worthwhile endeavour ?
comments ? thoughts ? This is an interesting idea, but one pitfall would seem to be the inconsistency in the way various thermal imagers present their images. Many (most?) are false colors, which are great for observation, but different products map different temperature ranges to different colors, so two different thermal imager models will show different colors for the same areas in a scene.
I'm not sure if that would kill any usefulness of the idea, but it might.
-Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
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Re: Thermal image database for equipment ?
On 1/21/22 12:47 AM, Tim Tuck wrote: I was having a discussion with a technician repairing some old equipment and he had taken IR pics with his FLIR to identify hot-spots.
His wish was that there should be a database of IR pics for know good equipment to compare against.
A quick search of the net didn't turn up anything beyond db's of IR for training AI mostly for security cameras.
Does such a database exist ?
If not, would creating such a database, that could be contributed to by all, be a worthwhile endeavour ?
comments ? thoughts ? This is an interesting idea, but one pitfall would seem to be the inconsistency in the way various thermal imagers present their images. Many (most?) are false colors, which are great for observation, but different products map different temperature ranges to different colors, so two different thermal imager models will show different colors for the same areas in a scene. I'm not sure if that would kill any usefulness of the idea, but it might. -Dave -- Dave McGuire, AK4HZ New Kensington, PA
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Re: HP 89441A / 89431A RF Section Help
Thanks Matt.? That's very good to know - I'm still poking around, trying to figure out where the problem actually lies.? I think my next step will be to trace out the +8V regulator circuit and compare it to others that don't have an overcurrent condition.? I'm hoping that the regulator drops the voltage when it thinks too much current is being drawn.? It's difficult to know for sure without a schematic. :)
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Hi,
Subject says it all.? I need a?83595c service manual.
My?83595c is working fine so far, but I don't like being caught with my pants down, except on rare occasions ;-)
Thanks,
Victor
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The counter on my 8640B sig gen is acting up.? When I first turn it on the most significant number on the display is wrong and is preceded by a decimal point.? For example if the gen is set to 51.2004 MHz the display shows .31.2004.? After a few minutes the display corrects itself.? It appears there is an electrolytic that is being reformed but that is just a guess.? How hard is it to get to the counter board?? Am I analyzing this wrong?
Thanks,
Bill A
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Re: New member (with a dso-x 3012a not booting), Summary - Fixed
On Fri, Jan 21, 2022 at 9:24 AM Tommy <tommy@...> wrote:
I eventually managed to restart the scope while logged in via the serial port and so loaded new firmware from USB, that was fortunate.
The scope is now in operation and I'm a happy camper!
As stated I first made a case with Keysight support and actually got a call from them, a nice call alright but the message was disappointing: we only do business with other businesses. I think they would have fixed my scope otherwise which is great for a 10 year old instrument but something to consider before buying Keysight if you're not a company!
Glad you got your scope running again. Regarding your other point, that is a disappointing situation. There is another long thread about that on the eevblog forum: From your email address I assume you are probably in Sweden. I don't know if the Keysight not-a-business-customer situation might be slightly better currently in the US than in some other parts of the world, and if it is, whether it will soon be just as bad. Previously I was able to order parts online directly from Keysight through their parts website. A couple of years ago that changed and you have to be registered with a business account to be able to order parts. A year or so ago I was still able to order parts by calling them and ordering over the phone. I don't know if that would still be possible today without a business account.
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Re: Looking for a scanned operating/service manual of the HP 215A Pulse Generator
Greetings,
I just checked and Dave at Artek Manuals () lists the operating/service manual for download at $12.50. ?If you want a CD as well add $2.25 if you are located in the USA, or $3.00 if outside the USA.
Artek manuals scans are top quality! ?I have ordered numerous manuals from Artek and have always been very pleased.
Best wishes,
Ken
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On 21Jan, 2022, at 11:22 AM, benj3867 via < benj3867@...> wrote:
Does anybody have an electronic copy of the manual of the HP 215A Pulse Generator that they can share?
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Looking for a scanned operating/service manual of the HP 215A Pulse Generator
Does anybody have an electronic copy of the manual of the HP 215A Pulse Generator that they can share?
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Re: 8594E input attenuator issue?
I stand corrected, my CAL output is -21 ¨C 22dB.
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From: [email protected] <[email protected]>
On Behalf Of Nicolas Mailloux
Sent: 21 janvier 2022 13:16
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] 8594E input attenuator issue?
?
Greg?: The thing is I suspected an issue with the o-rings, but they¡¯re all good. I¡¯m pretty sure the issue is not mechanical.
However , I managed to break one of the plunger and I need to replace it when I first disassembled it. The upside is I am now very comfortable manipulating it.
?
Next steps : find a plunger and bench the ATT correctly. I have a feeling my primary issue : AMPDT : ?GAIN FAIL is cause by something else.
I can get passed this error if I feed -17dB 300Mhz at the input. My CAL output is at around -18dB, which is also an issue.
?
Why I targeted the ATT, is because the marker would read -45dB or more when the ATT was not set to a multiple of 20 (-20dB, -40dB)
?
?
Failed O rings in these attenuators is a common problem as the equipment ages.? The material used to make them eventually dries out either from heat or environmental issues and becomes brittle thusly the O ring
frequently crumbles and falls off.? This then causes either non-actuation of an attenuator stage or intermittent operation at best.
?
We once tried to replace the O rings in an attenuator.? The first step was to measure a good item then try to find a replacement.? This required considerable disassembly of the attenuator then trying to find a
O-ring that had not aged to the point where it was not wither brittle or its dimensions had changed.? Then the selection process continued.? At that point it was not? known what material the O rings were made out of.? I did hear from another engineer to be
careful because some O rings will outgas affecting the contact reliability in the attenuator.? After randomly selecting a possibly suitable material the next step was to locate a small quantity of the O rings.? This resulted in eventually finding a manufacturer
who would provide some samples instead of us having to buy hundreds of them to satisfy a minimum order.
?
After all of this was done it was then decided that the total time and energy wasted I trying to ¡°make do¡± by an in-house repair was far overshadowed by simply sending the attenuator to the repair agency which
was the final outcome.
?
The O rings are there for a reason mainly to cushion the blow of the solenoid when it actuates.
?
Greg
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Re: 8594E input attenuator issue?
Greg?: The thing is I suspected an issue with the o-rings, but they¡¯re all good. I¡¯m pretty sure the issue is not mechanical.
However , I managed to break one of the plunger and I need to replace it when I first disassembled it. The upside is I am now very comfortable manipulating it.
?
Next steps : find a plunger and bench the ATT correctly. I have a feeling my primary issue : AMPDT : ?GAIN FAIL is cause by something else.
I can get passed this error if I feed -17dB 300Mhz at the input. My CAL output is at around -18dB, which is also an issue.
?
Why I targeted the ATT, is because the marker would read -45dB or more when the ATT was not set to a multiple of 20 (-20dB, -40dB)
?
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From: [email protected] <[email protected]>
On Behalf Of Greg Muir via groups.io
Sent: 21 janvier 2022 12:57
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] 8594E input attenuator issue?
?
Failed O rings in these attenuators is a common problem as the equipment ages.? The material used to make them eventually dries out either from heat or environmental issues and becomes brittle thusly the O ring
frequently crumbles and falls off.? This then causes either non-actuation of an attenuator stage or intermittent operation at best.
?
We once tried to replace the O rings in an attenuator.? The first step was to measure a good item then try to find a replacement.? This required considerable disassembly of the attenuator then trying to find a
O-ring that had not aged to the point where it was not wither brittle or its dimensions had changed.? Then the selection process continued.? At that point it was not? known what material the O rings were made out of.? I did hear from another engineer to be
careful because some O rings will outgas affecting the contact reliability in the attenuator.? After randomly selecting a possibly suitable material the next step was to locate a small quantity of the O rings.? This resulted in eventually finding a manufacturer
who would provide some samples instead of us having to buy hundreds of them to satisfy a minimum order.
?
After all of this was done it was then decided that the total time and energy wasted I trying to ¡°make do¡± by an in-house repair was far overshadowed by simply sending the attenuator to the repair agency which
was the final outcome.
?
The O rings are there for a reason mainly to cushion the blow of the solenoid when it actuates.
?
Greg
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Re: 8594E input attenuator issue?
Failed O rings in these attenuators is a common problem as the equipment ages.? The material used to make them eventually dries out either from heat or environmental issues and becomes brittle thusly the O ring frequently crumbles and falls off.? This then causes either non-actuation of an attenuator stage or intermittent operation at best.
?
We once tried to replace the O rings in an attenuator.? The first step was to measure a good item then try to find a replacement.? This required considerable disassembly of the attenuator then trying to find a O-ring that had not aged to the point where it was not wither brittle or its dimensions had changed.? Then the selection process continued.? At that point it was not? known what material the O rings were made out of.? I did hear from another engineer to be careful because some O rings will outgas affecting the contact reliability in the attenuator.? After randomly selecting a possibly suitable material the next step was to locate a small quantity of the O rings.? This resulted in eventually finding a manufacturer who would provide some samples instead of us having to buy hundreds of them to satisfy a minimum order.
?
After all of this was done it was then decided that the total time and energy wasted I trying to ¡°make do¡± by an in-house repair was far overshadowed by simply sending the attenuator to the repair agency which was the final outcome.
?
The O rings are there for a reason mainly to cushion the blow of the solenoid when it actuates.
?
Greg
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Re: 8594E input attenuator issue?
Found what I was looking for. Breadboarding done.
?
?
Now actively looking for a plunger.
?
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From: [email protected] <[email protected]>
On Behalf Of Nicolas Mailloux
Sent: 21 janvier 2022 11:05
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] 8594E input attenuator issue?
?
Anyone can pinpoint me to the schematics of the drive board for my 33321-60036 ATT ? While waiting to find a replacement plunger, I will breadboard the necessary to electrically actuate
the solenoids. I am not familiar with HP documentation, but I heard something about looking for a CLIP. ?
?
?
?Since I have a plunger/piton broken at the DC Block, I can¡¯t make measurements easily. I am getting inconsistent measurements when tje ATT is assembled.?
At this point here¡¯s what I think I should do :
Replace the broken plunger to put the ATT in mechanical order
Bench measure the ATT correctly?
Show a video of the issue if it still persists.?
Looking on ebay, I see many DC-4Ghz 70 dB ATT. The ones that are not the same exact number as mine (33321-60036) seem to only differ in their electronic driver board. They are not too expensive at around 60$. (I talk about other 33321 series
ATT)
However, for some reason, the same ATT as mine cost 5 times more, that is a bummer.?
With all the trouble shooting done to date, I think my ATT was fine and the problem is elsewhere :(
A fellow member of the group offered to send me one of his ATT to help me fix mine.?
?
?
?
Hi,
Yes its correct that its not needed to have and output terminator to measure the DC resistance, but you need to calculate the resistance, as you have done.
So as you write, 61.11ohm is correct to measure between input and ground for a 10dB attenuator, when the output is not terminated.
But when a terminator is added to the output , it should then measure 50 ohm.?
Nicolas, your previous measurement of resistance between input and output, and input to ground and output to ground, all these values are correct for 10, 20 and 40 dB attenuators.
But that you did not get 50 ohm when you used an terminator on the output, you should check that the terminator measures 50 ohm, and also check that the DC-block was not active.
If this is OK, try moving the terminator to the opposite side, and measure the other way, as there might be a bad contact on one side.
?
On Thu, Jan 20, 2022 at 8:42 PM Ozan <ozan_g@...> wrote:
50-ohm termination is needed to get the correct attenuation but for measuring resistances it is not needed.?
From your earlier measurements it looks like:
PAD2 is 20dB section
PAD3 is 40dB section
PAD4 is 10dB section
If we treat each section as a pi attenuator (I don't know if it is valid with these units) expected values with open termination are?
10dB section (PAD4?)
input or output to ground 61.11ohm
Across 51.95
20dB section (PAD2?)
input or output to ground 51ohm
Across 81.8ohm
40dB section (PAD3?)
input or output to ground ~50ohm
Across 98-ohm
Doesn't look like there is a gross failure.?
Next you can do a DC attenuation check. Apply 1V DC to one side of 40dB attenuator and measure the voltage at the other side while terminating to 50-ohm. Correct voltage is 10mV, from scope measurements we expect wrong value of ~ 20mV. Then swap the input and
output side and do the same.
This will tell at least at DC if the attenuation is correct.?
Ozan
?
?
On Thu, Jan 20, 2022 at 11:21 AM, Nicolas Mailloux wrote:
Hi!
I put a 50ohm termination on the input side and measured at the output.
PAD 2 and 3 are giving 50 ohm, while PAD 4 is measuring 61.1 ohm as my previous measurements did.
?
?
Remember that an attenuator must be terminated in 50 ohms to have the correct attenuation.
You could do a simple test with your DMM, with the attenuator assembled (except for the cover over the control solenoids.
Put a 50 ohm terminator on one side, and measure between center and screen on the other side.
Move the solenoids, so only one pad is active at a time, and you should measure very close to 50 ohm on this connector.
Of course with the exception of the DC-block.
?
Ozan?: These measurements are from input to output.
PAD 2 : 81.69 ohm
PAD 3 : 98.04 ohm
PAD 4 : 51.65 ohm
?
These are from input to ground :
PAD 2 : 51.05 ohm
PAD 3 : 49.95 ohm
PAD 4 : 60.96 Ohm
?
There are from output to ground :
PAD 2 : 51.10
PAD 3 : 50.16
PAD 4 : 61.23
?
?
On Thu, Jan 20, 2022 at 07:58 AM, Nicolas Mailloux wrote:
n8zmTWH@... : I do not have/searched the schematics of my particular ATT. I based my assumptions on a previous post from someone that attached schematics.
They may not be the right ones.
?
My exact model number is : 33321-60036 it goes to 70dB I think. My 8594E is from 9kHz to 2.9GHz.
Measuring the pads where the contact blades touch when selected, still in the aluminum block I get these readings :
They are in order from Input to Output.
?
PAD 2 : 81.69 ohm
PAD 3 : 98.04 ohm
PAD 4 : 51.65 ohm
?
Both service manual and CLIP show 10dB/20dB/40dB sections.
The pads have three terminals, input/output/ground (input/output being symmetric). Ground is connected to the metal frame.? Are above resistance measurements from one pad to ground? It may or may not tell much but what resistance do you measure from each side
to ground??
Ozan
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maurit
Froggie the Gremlin
Dave McGuire