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Re: Frequency calibration?

 

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They say coffee helps you live longer, I don’t know about how true that is but I do know that it definitely makes me enjoy the time I do have much more!


Peter

On Oct 10, 2017, at 4:11 PM, `Richard Knoppow dickburk@... [hp_agilent_equipment] <hp_agilent_equipment@...> wrote:

?

?? There are many of us who are slaves to coffee. Have few other bad habits but I can't even talk in the morning before drinking a cup.

On 10/10/2017 11:02 AM, Bob Bownes bownes@... [hp_agilent_equipment] wrote:
Correct! Need more caffeinated beverage. Thanks!


--
Richard Knoppow
dickburk@...
WB6KBL
Re: Frequency calibration?

 

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?????? There are many of us who are slaves to coffee. Have few other bad habits but I can't even talk in the morning before drinking a cup.

On 10/10/2017 11:02 AM, Bob Bownes bownes@... [hp_agilent_equipment] wrote:
Correct! Need more caffeinated beverage. Thanks!


-- 
Richard Knoppow
dickburk@...
WB6KBL
Re: Fast Rise/Fall Time Pulser

 

Yes, works as advertised as far as I can tell.? There is plenty of discussion and many screenshots here:



On Tue, Oct 10, 2017 at 12:19 PM, Larry McDavid lmcdavid@... [hp_agilent_equipment] <hp_agilent_equipment@...> wrote:

?

There has been discussion recently about generating fast rise/fall time
pulses by various means. Here is a link to a Leo Bodnar device that will
provide <40 ps rise/fall time, 50% duty cycle, 10 MHz pulses:



This is built on a small PWB with integral BNC connector, powered by 5
vdc through a USB B connector; a trigger output is provided. Price is US$68.

I've ordered one of these for testing.

Is anyone here using one of these?

--
Best wishes,

Larry McDavid W6FUB
Anaheim, California (SE of Los Angeles, near Disneyland)
Re: Frequency calibration?

 

Two questions for the original poster: How accurate do you need (want) to be? and what are you using the counter for?
Time and frequency precision can become an obsession - Time Nuttery.

Robert G8RPI.
Fast Rise/Fall Time Pulser

 

There has been discussion recently about generating fast rise/fall time pulses by various means. Here is a link to a Leo Bodnar device that will provide <40 ps rise/fall time, 50% duty cycle, 10 MHz pulses:



This is built on a small PWB with integral BNC connector, powered by 5 vdc through a USB B connector; a trigger output is provided. Price is US$68.

I've ordered one of these for testing.

Is anyone here using one of these?

--
Best wishes,

Larry McDavid W6FUB
Anaheim, California (SE of Los Angeles, near Disneyland)
Re: Frequency calibration?

 

Correct! Need more caffeinated beverage. Thanks!

On Tue, Oct 10, 2017 at 2:00 PM, `Richard Knoppow dickburk@... [hp_agilent_equipment] <hp_agilent_equipment@...> wrote:

?

?? On a standard scope with the same signal on X and Y in phase is a line at 45degrees to the right, 180degrees out of phase is a straight line tilted 45 degrees to the left, a circle is 90 degrees out of phase. This assumes equal phase response of of the X and Y amplifiers in the scope.
??? If there is drift the pattern will rotate.

On 10/10/2017 7:38 AM, Bob Bownes bownes@... [hp_agilent_equipment] wrote:
?
Another is feed one into X, one into Y of an oscilloscope. In phase is a circle. Out of phase is a diagonal line.?
frequency multiples will show pretty patterns from your favorite SciFi movies of the 50's and 60's. 


--
Richard Knoppow
dickburk@...
WB6KBL
Re: Frequency calibration?

 

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?????? On a standard scope with the same signal on X and Y in phase is a line at 45degrees to the right, 180degrees out of phase is a straight line tilted 45 degrees to the left, a circle is 90 degrees out of phase. This assumes equal phase response of of the X and Y amplifiers in the scope.
????????? If there is drift the pattern will rotate.

On 10/10/2017 7:38 AM, Bob Bownes bownes@... [hp_agilent_equipment] wrote:
???
Another is feed one into X, one into Y of an oscilloscope. In phase is a circle. Out of phase is a diagonal line.???
frequency multiples will show pretty patterns from your favorite SciFi movies of the 50's and 60's. 


-- 
Richard Knoppow
dickburk@...
WB6KBL
Re: VNA design engineer on the list?

 

Dr. Joel Dunsmore hangs out in the Forums on HP/Agilent/Keysight.


On Tue, Oct 10, 2017 at 1:16 PM, Reginald Beardsley pulaskite@... [hp_agilent_equipment] <hp_agilent_equipment@...> wrote:

?

If anyone here designed commercial VNAs, I'd like to call attention to some recent posts I've made to the EEVblog metrology forum on the topic of using an SA and a computer to measure amplitude and phase.

If the names Wiener, Levinson and Hilbert are unfamiliar it's not likely to make any sense.
VNA design engineer on the list?

 

If anyone here designed commercial VNAs, I'd like to call attention to some recent posts I've made to the EEVblog metrology forum on the topic of using an SA and a computer to measure amplitude and phase.

If the names Wiener, Levinson and Hilbert are unfamiliar it's not likely to make any sense.
Re: Frequency calibration?

 

By far and away the best choice is going to be a GPS disciplined oscillator such as an HP 3801A or a Thunderbolt. A good GPSDO should be good to at least 1x10^-10
? (1ppb) over the course of a day. ?
It will be the simplest as well. Take the 10MHz output and feed into the Ext Reference input on pretty much all of your lab equipment. Any good counter, signal generator, even bench scopes will have one. A simple video distribution amplifier will serve just fine to ship the signal to all of them at once. Don't forget to put one on the workbench someplace to plug it into whatever you are working on. :)

There are a variety of ways to to check the accuracy of your reference. One of the better ones is to look at jitter and phase difference over time. Feed one into the trigger on a time interval counter such as an HP5370 , the other into the input. The time interval between the two shouldn't change (it will), but the change over time and the jitter between the two will be very instructive. Using this, you can see changes over the course of days or weeks (depending on what data you save). There is a good HP App Note on jitter.



Another is feed one into X, one into Y of an oscilloscope. In phase is a circle. Out of phase is a diagonal line.?
frequency multiples will show pretty patterns from your favorite SciFi movies of the 50's and 60's.

This is a subject many have been drawn into very deeply. There is, in fact an entire mailing list devoted to the subject.

Beware however. It is a subject that can cost you a great deal of time and money. A man with one watch knows what time it is. A man with two is never sure. A man with 3 can make a very good guess however! That thinking can lead to owning several GPSDO's, a rubidium, and a cesium beam standard. Or several of each. Really. And taking your kids up mountains to prove relativity. Really. .


Bob


On Oct 10, 2017, at 08:49, Reginald Beardsley pulaskite@... [hp_agilent_equipment] <hp_agilent_equipment@yahoogroups.com> wrote:

?


I can't recall where, but someone posted a comment to the effect that the PPS output of their GPS unit had significant (~20 nS) jitter.

I'd suggest feeding the output of the reference to be checked to an MCU such as an STM32F4xx Discovery board along with the PPS from the GPS and counting the number of transitions between PPS outputs.

Have Fun!
Reg
Re: Schematics for HP 8558B SA

 

As Dave from Artek says, it is helpful to know the serial number of the unit. What you most likely want is the "Operation and Service Manual" for this unit. The part number for the manual is 08558-90102.

Keysight probably still has this posted on their website as that is where I got mine, but it is not perfect and there are a few schematic pages that are not scanned completely/properly. If Dave at Artek has this manual, I would consider ordering it from him - Dave's manuals are, well, pretty much perfect.

Is there a specific issue you are having with your 8558B? I have several of them in service and might be able to assist you with debug and replacement parts (other than wafer-switch rotors).

Ken
Re: Frequency calibration?

 

I can't recall where, but someone posted a comment to the effect that the PPS output of their GPS unit had significant (~20 nS) jitter.

I'd suggest feeding the output of the reference to be checked to an MCU such as an STM32F4xx Discovery board along with the PPS from the GPS and counting the number of transitions between PPS outputs.

Have Fun!
Reg
Re: Frequency calibration?

 

Ok. So you have a Trrimble Thunderbolt GPS??
Re: Frequency calibration?

 

Hi Anders,
with my counters, I put a 10 MHz sinewave from the GPSDO (thunderbolt)
on channel 1 of oscilloscope, triggering on it, then I put the
counter's 10 MHz reference to channel 2 and I trim the reference until
there's no (or barely) shifting of the timebase signal with respect to
the fixed (triggering) 10 MHz from GPSDO.
HTH
Frank IZ8DWF

On Tue, Oct 10, 2017 at 1:58 PM, anders.gustafsson@...
[hp_agilent_equipment] <hp_agilent_equipment@...> wrote:



What would be a reasonably cheap way of checking frequency calibration? I have an old hp 5328, with oven. I also have one of those cheap GPS modules where the PPS output can be reprogrammed. I set it to 1kHz and the counter showed 1.0000kHz. Sounds good?


There are u-blox modules that can be reprogrammed to output 10MHz and the 5328 can use an external 10MHz for timebase. Would such a module (below) work?
Frequency calibration?

 

What would be a reasonably cheap way of checking frequency calibration? I have an old hp 5328, with oven. I also have one of those cheap GPS modules where the PPS output can be reprogrammed. I set it to 1kHz and the counter showed 1.0000kHz. Sounds good?


There are u-blox modules that can be reprogrammed to output 10MHz and the 5328 can use an external 10MHz for timebase. Would such a module (below) work?



?
Re: Schematics for HP 8558B SA

 

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Paul

There are several different versions of the service manuals for the 8558B.??? In order to direct you properly could you please tell us the serial number of your unit

Dave
NR1DX
manuals@...

On 10/10/2017 2:54 AM, pdulaff@... [hp_agilent_equipment] wrote:
???

Hello


I have the service manual for the HP 8558B SA, but there are no detailed schematics included in the download PDF file I have. Can anyone point me at where t get the schematics ?


Thanks


Paul - WB2NMI



-- 
Dave
Manuals@...

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help hp5300a / 5303a manual service

[email protected]
 

Hello all, I'm looking for

hp5300a / 5303a manual service

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Roberto
Schematics for HP 8558B SA

 

Hello


I have the service manual for the HP 8558B SA, but there are no detailed schematics included in the download PDF file I have. Can anyone point me at where t get the schematics ?


Thanks


Paul - WB2NMI
Re: Fake fire New

 

What I thought amusing was that the reporter I was listening to essentially said "I've never heard of this company before".? Usually reporters stay away from personal comments when in the field, but since they were reporting all day, I guess they stretching things out and/or getting tired.??

It is annoying how they always make these things sound so bad (although this was a pretty nasty firestorm).? They also reported an earthquake in San Jose today that was widely felt, but I didn't feel a thing. :-(? ?(I like earthquakes...)

-Dave


From: "Jeremy Nichols jn6wfo@... [hp_agilent_equipment]"
To: hp_agilent_equipment@...
Sent: Monday, October 9, 2017 10:14 PM
Subject: Re: [hp_agilent_equipment] Fake fire New

?
The fire burned down the west slope of Sonoma Mountain (having destroyed many of the homes on the mountain) and stopped just as the slope flattened out, half a mile from our house. Many homes in the Fountaingrove area were damaged or destroyed; I'm glad to hear Keysight was not obliterated. No doubt, according to the news organs, the whole county and more burned to a crisp. As you say, care is needed in deciding which news sources to believe.

Jeremy


On Mon, Oct 9, 2017 at 8:49 PM caesarv@... [hp_agilent_equipment] <hp_agilent_equipment@...> wrote:
?
As some of you may know, Keysight's home of Santa Rosa, CA suffered a major fire.? Thousands of homes were destroyed as the fire raced down the hillside where Keysight is located.? ABC News (our ch 7) improperly reported that the entire Keysight compound was completely destroyed.? In actuality, only two temporary (modular) buildings were burned.? This is a tiny fraction of the floor space.? A few rental cars also burned. We did lose our credit union office but that is why we have ATM cards.

Never trust a singular source of news data.



--
4.
Re: Fake fire New

 

The fire burned down the west slope of Sonoma Mountain (having destroyed many of the homes on the mountain) and stopped just as the slope flattened out, half a mile from our house. Many homes in the Fountaingrove area were damaged or destroyed; I'm glad to hear Keysight was not obliterated. No doubt, according to the news organs, the whole county and more burned to a crisp. As you say, care is needed in deciding which news sources to believe.

Jeremy


On Mon, Oct 9, 2017 at 8:49 PM caesarv@... [hp_agilent_equipment] <hp_agilent_equipment@...> wrote:
?

As some of you may know, Keysight's home of Santa Rosa, CA suffered a major fire.? Thousands of homes were destroyed as the fire raced down the hillside where Keysight is located.? ABC News (our ch 7) improperly reported that the entire Keysight compound was completely destroyed.? In actuality, only two temporary (modular) buildings were burned.? This is a tiny fraction of the floor space.? A few rental cars also burned. We did lose our credit union office but that is why we have ATM cards.


Never trust a singular source of news data.




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