I was using the Hp 436A in the 1980s, and the 438A was a significant improvement, in being able to read forward and reflected power from a dual directional coupler, for example, with built in math abilities. I didn't see the 437A until the 1990s. We bought a few of them, and quickly found that they are not as reliable as their predecessors. I have scrapped more than one dead 437A while the 438A models are still going.
You can tell about old Hp instruments, if they have LED 7 seg displays and the click style rounded corner buttons, they came before the ones with the rubbery "flubber" square cornered buttons. But their scopes came from a different style again.
These days we buy the N1912A with N1921A sensor, as we are measuring pulsed RF power. I like a Boonton model as well. The specs for the Keysight meters are more detailed where the Boonton has some vague specs that are surprising.?
John Lyles
-------------------------------------------------------
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E4418A/4419A vs N1913A/1914A
Can anyone explain the major differences between these two series of power meters?
I have a number of E4418A/4419As and they have proven reliable and easy to use, except for one which does not calibrate correctly (after calibrating, the 0dBm reading is off, and this is true even if I use an alternative cal siggen). I haven't figured out how to fix that problem but if anyone knows how to do it...
The N1913A/1914A are newer and more expensive. Any major advantages making the higher price worthwhile?
Thanks!
Jim
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Re: FS: (US) HP 83525A and 83522A RF Plug-ins for 8350A/B Sweep Generator
The HP 83522A has been sold. Thank you for looking. The HP 83525A is still available and ready to ship.
Details are here:?
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Clamp tip for hp current probe
Hello All,
I have an hp 01110-61601 Current Probe that needs the clamp which threads at the tip. Does anyone have any of these they would be willing to part with?
Thanks in advance.
Christopher Tucker
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Re: Which Vector network analysis book to buy - help
On 9/4/22 06:26, Andrew Hakman wrote: Oh god, one of the books on Algorithms you're talking about must be this one
Yup, got that one. While I do like that book, it's a bit too academic, and I'm more on the practical side. My favorite is "Algorithms" by Robert Sedgewick. The book of the class I hated the most, and practically the only class I really cared about that I did poorly in (and the majority of the class did poorly in too). I always loved how the prof started almost every lecture of that class with a huge sigh - he clearly hated teaching that class, and it showed in the performance of the entire class!
I never thought to get a different book, I just took the less than stellar mark and the hit to my GPA and moved on... Being goal-oriented is good. Despite the sales job universities give us since birth, it's actually possible to learn things outside of a school. And it seems like as time progresses, no one knows jack s*it about algorithms or data structures at all. I recently had the (dis)pleasure of interviewing people applying for jobs with "Data Science" focuses - you ask them anything about algorithms or data structures, or complexity / big O notation, and they don't have the first clue about any of it. Then on top of that, EVERYONE now is an expert at Python / C / C++ according to their resume, even if they're a physics major, because at some point they wrote 5 lines of code for some experiment they did one time. Then you ask them "ok, if you know C and C++, what's the fundamental difference between the two?", and once again you get silence back as a response (or the incorrect answer). Yup. And people are just fine with that. China is eating our lunch because they've earned it. -Dave -- Dave McGuire, AK4HZ New Kensington, PA
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From the units I have and use about 45-60 minutes is reasonable. I use an external reference to drive them so they are stable very quickly. Paul WB8TSL
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I have a 5245L chassis that I set up for use only as a signal source. I mounted a small incandescent lamp on the front panel, and wired it to the juice that drives the oven heater. It's a sine wave that varies in amplitude (not just an on/off heater), so I can "see" the feedback loop settle in as the temp stabilizes.
Pete
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toggle quoted message
Show quoted text
-------- Original message -------- From: Harold Foster <halfoster@...> Date: 9/4/22 3:51 AM (GMT-08:00) Subject: Re: [HP-Agilent-Keysight-equipment] 5245L warm up
Per the SM 72 hours, but for general usage I have found 30 minutes to 1 hour to be plenty. Hal
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Re: Which Vector network analysis book to buy - help
James Thurber, in a parody of an advice column; Doctor, I have books the way some people have mice. Answer: I can't tell if you are complaining or bragging.?
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BTW: The warm up time is given in the "Accuracy" section of the Performance Check.
Hal
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Per the SM 72 hours, but for general usage I have found 30 minutes to 1 hour to be plenty.
Hal
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Re: Which Vector network analysis book to buy - help
Oh god, one of the books on Algorithms you're talking about must be this one
The book of the class I hated the most, and practically the only class I really cared about that I did poorly in (and the majority of the class did poorly in too). I always loved how the prof started almost every lecture of that class with a huge sigh - he clearly hated teaching that class, and it showed in the performance of the entire class!
I never thought to get a different book, I just took the less than stellar mark and the hit to my GPA and moved on...
And it seems like as time progresses, no one knows jack s*it about algorithms or data structures at all. I recently had the (dis)pleasure of interviewing people applying for jobs with "Data Science" focuses - you ask them anything about algorithms or data structures, or complexity / big O notation, and they don't have the first clue about any of it. Then on top of that, EVERYONE now is an expert at Python / C / C++ according to their resume, even if they're a physics major, because at some point they wrote 5 lines of code for some experiment they did one time. Then you ask them "ok, if you know C and C++, what's the fundamental difference between the two?", and once again you get silence back as a response (or the incorrect answer).
?? I've always done the same thing with most technical subjects.
Algorithms is a favorite example.? I have at least a dozen books on
algorithms by different authors.? There's a significant amount of
overlap in the specific algorithms they cover, but different authors
explain things very differently, and I find that I gain a more thorough
understanding when I read similar material written in different ways or
from different points of view.
? ?Of course the downside is a library of 1300+ books, but really, I
don't have any problem with that. :)
? ? ? ? ? ? ? -Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
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The operating manual that I have is almost 90MB. It is still uploading, but it should be done by 0600:
On Sun, Sep 4, 2022 at 1:10 AM Richard Knoppow < dickburk@...> wrote: I just pulled my 6245L out of storage.? ?Works fine, I have the big service manual but no operating manual and there does not seem to be one on line.?? First, does anyone know of a source,? my main question is how long does it have to be powered up for the oven to stabilize?? No hint in the service manual.? Also, what is the line demand for the oven only.? I used to use these every day.? We just left it urged in all rhe time.? ?Oven in mine seems to work, stays warm all the time.? I set the crystal zero beat with wwv after running it overnight, doesn't move.??
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Re: HP instrument measuring “RMS Power”
I think this page describes where the confusion comes from:
So yes, there is no meaningful RMS power by the literal
definition.
Best regards,
Job
PH4AS
On 03-09-2022 11:34, Dr. David Kirkby,
Kirkby Microwave Ltd wrote:
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Show quoted text
On Sat, 3 Sep 2022 at 07:48, tgerbic < tgerbic@...> wrote:
The 434A is a calorimetric meter. It is calibrated using by
measuring a DC power supply and the calibration port on the
front provides a DC signal. I suspect it would effectively
be RMS since it is the same wattage measurement for AC as
DC.
--
T. Gerbic
Central California
The mean AC power provides the same heating as
DC. So RMS watts have no practical use, but that
doesn’t stop them being used in the wrong places.?
For a sine wave feeding a resistor, the mean
power dissipated in the resistor is not the same as the RMS
power. I did once work out the maths of it, but can’t recall
the difference - if you Google RMS power, I am sure you will
find articles showing ?RMS power is a pointless
measurement.?
But as I note from both Analog Devices and
Minicircuits, even big companies make the error
occasionally.? Keysight seem immune - I can’t see any
Keysight products that claim to measure RMS power.?? But I
have seen the term on some bit of test equipment. I thought
it was old HP, but it might have been Marconi.?
--
Dr. David Kirkby,
Kirkby Microwave Ltd,
drkirkby@...
Telephone 01621-680100./ +44 1621 680100
Registered in England & Wales, company number 08914892.
Registered office:
Stokes Hall Lodge, Burnham Rd, Althorne, Chelmsford, Essex, CM3
6DT, United Kingdom
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Re: Which Vector network analysis book to buy - help
Actually, Carson made an explicit statement condemning efforts to
develop FM: "This method of modulation inherently distorts
without any compensating advantages whatsoever".
That sentence pounded several nails in the coffin. Carson was a
superb mathematician (the man knew his Bessel!). His paper on FM
was absolutely rigorous until the end. It was mainly concerned
with showing that FM was not a way to reduce bandwidth (which was
the original motivation for its invention). He was right about
that, but he failed to consider SNR, which is what Armstrong cared
about.
--Cheers,
Tom
--
Prof. Thomas H. Lee
Allen Ctr., Rm. 205
350 Jane Stanford Way
Stanford University
Stanford, CA 94305-4070
On 9/3/2022 22:24, Richard Knoppow
wrote:
toggle quoted message
Show quoted text
There is a fairly good bio on Wikipedia, search
for John Renshaw Carson. Carson wrote extensively on modulation
theory and designed bell systems carrier telephone system.
He wrote an analysis of FM in which he concluded
that narrow band FM was not advantageous.? Armstrong refuted
this.? I don't think Carson said FM wouldn't work.? Armstrong
was clobbered by David Sarnoff for reasons thT were largely
personal.? After Armstrong suicide his wife continued the
litigation against RCA and eventually prevailed. Btw, she had
been Sarnoff secretary.
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Re: Which Vector network analysis book to buy - help
There is a fairly good bio on Wikipedia, search for John Renshaw Carson. Carson wrote extensively on modulation theory and designed bell systems carrier telephone system. He wrote an analysis of FM in which he concluded that narrow band FM was not advantageous.? Armstrong refuted this.? I don't think Carson said FM wouldn't work.? Armstrong was clobbered by David Sarnoff for reasons thT were largely personal.? After Armstrong suicide his wife continued the litigation against RCA and eventually prevailed. Btw, she had been Sarnoff secretary.
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I just pulled my 6245L out of storage.? ?Works fine, I have the big service manual but no operating manual and there does not seem to be one on line.?? First, does anyone know of a source,? my main question is how long does it have to be powered up for the oven to stabilize?? No hint in the service manual.? Also, what is the line demand for the oven only.? I used to use these every day.? We just left it urged in all rhe time.? ?Oven in mine seems to work, stays warm all the time.? I set the crystal zero beat with wwv after running it overnight, doesn't move.??
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Re: Which Vector network analysis book to buy - help
And the "they" was pretty much a single "he": John Carson (no known relationship to the late US TV talkshow host). " His reputation (he invented DSB-SC AM and SSB) meant that nearly everyone took his word as gospel. Fortunately, Armstrong chose to push onward, nonetheless.
--Tom
--
Prof. Thomas H. Lee
Allen Ctr., Rm. 205
350 Jane Stanford Way
Stanford University
Stanford, CA 94305-4070
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Show quoted text
On 9/3/2022 20:31, Bruce wrote: Thanks - and I probably will.? You might be interested in reading up on the advent of FM radio - "They" said it wouldn't work.
Cheer!
Bruce
Quoting Richard Knoppow <dickburk@...>:
Just because this is relevant to something I am studying, I? find it helpful to have more than one book on anything I am trying to learn. Simply because one author is apt to leave something out or be confusing.? ?I have? been studying the history of wireless/radio.? Actually a long standing interest.? In the last few weeks I have read three books and will re read a couple of others.? One of the books I just finished glosses over some stuff but I knew it from other sources.? However he so added some details that were new to me so there is something to be gained from multiple sources.? ?I am long retired from -hp- and also have a healthy respect for R&S. Get both books unless they are a fortune.Sent from my Galaxy
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Re: Which Vector network analysis book to buy - help
On 9/3/22 23:12, Richard Knoppow wrote: Just because this is relevant to something I am studying, I? find it helpful to have more than one book on anything I am trying to learn. Simply because one author is apt to leave something out or be confusing.? ?I have? been studying the history of wireless/radio. Actually a long standing interest.? In the last few weeks I have read three books and will re read a couple of others.? One of the books I just finished glosses over some stuff but I knew it from other sources. However he so added some details that were new to me so there is something to be gained from multiple sources.? ?I am long retired from -hp- and also have a healthy respect for R&S. Get both books unless they are a fortune. I've always done the same thing with most technical subjects. Algorithms is a favorite example. I have at least a dozen books on algorithms by different authors. There's a significant amount of overlap in the specific algorithms they cover, but different authors explain things very differently, and I find that I gain a more thorough understanding when I read similar material written in different ways or from different points of view. Of course the downside is a library of 1300+ books, but really, I don't have any problem with that. :) -Dave -- Dave McGuire, AK4HZ New Kensington, PA
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Re: Which Vector network analysis book to buy - help
Thanks - and I probably will. You might be interested in reading up on the advent of FM radio - "They" said it wouldn't work.
Cheer!
Bruce
Quoting Richard Knoppow <dickburk@...>:
toggle quoted message
Show quoted text
Just because this is relevant to something I am studying, I? find it helpful to have more than one book on anything I am trying to learn. Simply because one author is apt to leave something out or be confusing.? ?I have? been studying the history of wireless/radio.? Actually a long standing interest.? In the last few weeks I have read three books and will re read a couple of others.? One of the books I just finished glosses over some stuff but I knew it from other sources.? However he so added some details that were new to me so there is something to be gained from multiple sources.? ?I am long retired from -hp- and also have a healthy respect for R&S. Get both books unless they are a fortune.Sent from my Galaxy
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Christopher Tucker
Dave McGuire
saipan59 (Pete)
Harold Foster
Michael A. Terrell