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Hello Group,
I am pondering the choice regarding purchasing an HP VNA.
What model of HP VNA would be a good choice regarding this topic, for a retired hobbyist on a budget?
I have a good selection of Test Equipment in my selection, acquired over time. A lot of it is HP gear.
I have worked my entire career in the field of electronics, mostly working in the field on servicing and maintaining electronic systems. Using a lot of other HP gear but not really using a VNA.
I saw a HP8753B for sale and I would like to ask the group if this would be a distinct unit? It has option 006, (6GHz) range.
Are they hard to repair? Any weak points on these units?
All recommendations accepted and any comments.
?
?
Thanks in advance,
George
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Based upon your post, aside from HP VNAs, and depending your intended use(s) for one, you may want to take a look at the various Nano VNAs available.
There are several groups.io groups which are forums for the Nano VNAs.
DaveD KC0WJN
Thanks for all the fish.
============================== All spelling mistakes are the responsibilty of the reader (Rick Renz, STK, ca. 1994) ==============================
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On Oct 19, 2024, at 13:02, G H via groups.io <gkhoefer@...> wrote:
?
Hello Group,
I am pondering the choice regarding purchasing an HP VNA.
What model of HP VNA would be a good choice regarding this topic, for a retired hobbyist on a budget?
I have a good selection of Test Equipment in my selection, acquired over time. A lot of it is HP gear.
I have worked my entire career in the field of electronics, mostly working in the field on servicing and maintaining electronic systems. Using a lot of other HP gear but not really using a VNA.
I saw a HP8753B for sale and I would like to ask the group if this would be a distinct unit? It has option 006, (6GHz) range.
Are they hard to repair? Any weak points on these units?
All recommendations accepted and any comments.
?
?
Thanks in advance,
George
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An HP VNA, and a budget usually don't go well together. The VNA is only a small part of the story, as it will need to be calibrated every time you use it, so you will need a calibration standards kits, which (for one that is good) often exceeds the price of the used VNA bargain. You will also need adapters that connect between the very expensive, and delicate connectors on the VNA, and the rough and tumble cables and connectors that you may use to connect to your fixtures. Oh, and you shouldn't really use any rough and tumble connectors and cables. Good VNA connectors and cables are also expensive. You haven't mentioned what you want to do with your VNA, so I would also include some good books and a lot of learning in the mix. If you just want to experience a VNA, and try it on a bunch of different things, there are some new little kits that come with everything you need, for under $50. Look into the nano VNA. It is an excellent VNA for someone who is new to the whole idea. -Chuck Harris On Sat, 19 Oct 2024 10:02:34 -0700 "G H via groups.io" <gkhoefer@...> wrote: Hello Group,
I am pondering the choice regarding purchasing an HP VNA.
What model of HP VNA would be a good choice regarding this topic, for
a retired hobbyist on a budget?
I have a good selection of Test Equipment in my selection, acquired
over time. A lot of it is HP gear.
I have worked my entire career in the field of electronics, mostly
working in the field on servicing and maintaining electronic systems.
Using a lot of other HP gear but not really using a VNA.
I saw a HP8753B for sale and I would like to ask the group if this
would be a distinct unit? It has option 006, (6GHz) range.
Are they hard to repair? Any weak points on these units?
All recommendations accepted and any comments.
Thanks in advance,
George
|
George,
The 8753B will need a test set like the 85047A to reach 6GHz, or the 85046A up to 3GHz.? The 8753D has a built in test set, and is available in 3GHz and 6GHz versions.? These all use APC-7 connectors, so you will need adapters and cables to work with whatever connector system you use.? The adapters may be expensive.? You will also need calibration standards (short, open, and load) which can also get expensive.
?
As others have mentioned, the NanoVNA series of devices is available at very low cost and includes SMA cables and standards that are acceptable for many purposes.? You would still need some adapters if you use connectors other than SMA.? I personally have a couple of 6GHz 8753Ds, but I find that for most measurements I use the NanoVNA units because of their portability.
?
If you want the solid feel of an HP unit, you might want to look at the 8712 (1.3GHz) or 8714 (3GHz) units.? They have built-in test sets and use N connectors.
--John Gord
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As a retired hobbyist, I doubt very much that he will need to do all the calibrations you mention. Seems like he would just like to play with one. A lot can be accomplished and learned without most of what you mention. Welcome him, do not scare him away. – Mike ? Mike B. Feher, N4FS 89 Arnold Blvd. Howell NJ 07731 908-902-3831 ?
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-----Original Message-----
From: [email protected] <[email protected]> On Behalf Of Chuck Harris
Sent: Saturday, October 19, 2024 1:37 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] HP8753B VNA question regarding if I purchase one ? An HP VNA, and a budget usually don't go well together. ? The VNA is only a small part of the story, as it will need to be calibrated every time you use it, so you will need a calibration standards kits, which (for one that is good) often exceeds the price of the used VNA bargain. ? You will also need adapters that connect between the very expensive, and delicate connectors on the VNA, and the rough and tumble cables and connectors that you may use to connect to your fixtures.? Oh, and you shouldn't really use any rough and tumble connectors and cables. Good VNA connectors and cables are also expensive. ? You haven't mentioned what you want to do with your VNA, so I would also include some good books and a lot of learning in the mix. ? If you just want to experience a VNA, and try it on a bunch of different things, there are some new little kits that come with everything you need, for under $50. ? Look into the nano VNA.? It is an excellent VNA for someone who is new to the whole idea. ? -Chuck Harris ? ? ? ? On Sat, 19 Oct 2024 10:02:34 -0700 "G H via groups.io" <gkhoefer@...> wrote: > Hello Group, > > I am pondering the choice regarding purchasing an HP VNA. > > What model of HP VNA would be a good choice regarding this topic, for > a retired hobbyist on a budget? > > I have a good selection of Test Equipment in my selection, acquired > over time. A lot of it is HP gear. > > I have worked my entire career in the field of electronics, mostly > working in the field on servicing and maintaining electronic systems. > Using a lot of other HP gear but not really using a VNA. > > I saw a HP8753B for sale and I would like to ask the group if this > would be a distinct unit? It has option 006, (6GHz) range. > > Are they hard to repair? Any weak points on these units? > > All recommendations accepted and any comments. > > Thanks in advance, > > George > > > > > ? ? ? ?
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I second John’s wise words. The 8752 is also a nice 3GHz machine that has a built in test set.?
I love my 8753D/E and S units and they can be quite economical if you are in no hurry and don’t need to have them shipped.?
Not all of the HPs have APC7’s, but beware the ones that have Ns. Some, but hardly all, are 75Ω, and buying one expecting otherwise can ruin your day. I have had at least one 50Ω N connectors 8753.?
Also beware the cost of test cables. Good ones are expensive. But you can usually find some for sub $100 at MIT flea hamfest or some place similar.?
Good luck!
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On Oct 19, 2024, at 14:06, John Gord via groups.io <johngord@...> wrote:
? George,
The 8753B will need a test set like the 85047A to reach 6GHz, or the 85046A up to 3GHz.? The 8753D has a built in test set, and is available in 3GHz and 6GHz versions.? These all use APC-7 connectors, so you will need adapters and cables to work with whatever connector system you use.? The adapters may be expensive.? You will also need calibration standards (short, open, and load) which can also get expensive.
?
As others have mentioned, the NanoVNA series of devices is available at very low cost and includes SMA cables and standards that are acceptable for many purposes.? You would still need some adapters if you use connectors other than SMA.? I personally have a couple of 6GHz 8753Ds, but I find that for most measurements I use the NanoVNA units because of their portability.
?
If you want the solid feel of an HP unit, you might want to look at the 8712 (1.3GHz) or 8714 (3GHz) units.? They have built-in test sets and use N connectors.
--John Gord
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If the 8753B is a good price and the screen is OK then it is a far superior instrument to the "Nano" devices. The displays can get? bit dim with age. If you keep the unit there is a LED upgrade that also give colour.
You do NOT have to have a test set to use the instrument.?
A test set makes things easy but for simple transmission tests you just need a resistive power splitter and some cables. For reflection a directional coupler is required. This could be a single component. For a bit more versatility at lower cost a HP 8502A can be used.
You will learn a lot more about network analyser operation using an 8753, a power splitter and directional coupler than touching the screen on a Nano or even a full switching test set.
Talking about the cost of "proper" calibration kits and Nanos on the same thread is a bit of an oxymoron.? A home made short and open and a reasonable quality standard termination is good enought for most users. The kits supplied with the Nano are not metrology grade....
Dave, the group owner sells excellent cal kits at sensible prices.
?
Robert G8RPI
(8753B, 85047A, 85046B, 8754A, 8502A, DG8SAQ and Anritsu S311 owner with both HP and Kirby Microwave Cal kits)
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Hello Group,
I am pondering the choice regarding purchasing an HP VNA.
What model of HP VNA would be a good choice regarding this topic, for a retired hobbyist on a budget?
I have a good selection of Test Equipment in my selection, acquired over time. A lot of it is HP gear.
I have worked my entire career in the field of electronics, mostly working in the field on servicing and maintaining electronic systems. Using a lot of other HP gear but not really using a VNA.
I saw a HP8753B for sale and I would like to ask the group if this would be a distinct unit? It has option 006, (6GHz) range.
It very much depends on your frequency range of interest, but for use to 6 GHz, you would be hard to beat an 8753B or later. There's a lot of information on my company websites about the 8753 series.?
You will generally want to use it with an S-parameter test set. Either the 3 GHz? 85046A or 6 GHz 85047A. Do not buy an 85046B, as that's 75 ohm. I did actually convert a 75 ohm 85046B to 50 ohm, by stripping the parts from a similar 1.3 GHz 50 ohm test set. I was not bothered about performance above 1.3 GHz, as I have a 20 GHz VNA too. At the time it was economical to do the conversion, but I don't think it is now.
Models with options like the 6 GHz 006 will generally fetch more than instruments without it, but don't worry about buying options, as someone here will supply codes to unlock all the options. So option 002 (not that useful), 006 (6 GHz), and 010 (time domain) are easy to get free.
My company sells VNA calibration kits, and more customers have 8753s than any other single VNA. It's very popular among both hobbyists and commercial companies. Last year I visited the National Physical Laboratory (NPL) in the UK, and they have an 8753 too. (NPL also have the more advanced 8510C, and the mega expensive PNA-X series).
Are they hard to repair? Any weak points on these units?
? There's a lot of information available on this site on them, including at least some circuit diagrams.
All recommendations accepted and any comments.
If you can get one at a reasonable price, I don't think you will regret it.?
?
Thanks in advance,
George
Dave
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I see, so I should pander and lie to him. I will try to
remember that.
Investing $50 in a nanoVNA, to see if he even knows what
a VNA should do, or has any use for one, is foolish...
Far better to spend $3K to 10K only to find out he has no
interest, or need for a VNA.
Check. Got it.
-Chuck Harris
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On Sat, 19 Oct 2024 22:22:27 -0400 "Mike Feher" <n4fs@...> wrote: As a retired hobbyist, I doubt very much that he will need to do all
the calibrations you mention. Seems like he would just like to play
with one. A lot can be accomplished and learned without most of what
you mention. Welcome him, do not scare him away. - Mike
Mike B. Feher, N4FS
89 Arnold Blvd.
Howell NJ 07731
908-902-3831
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I see, so I should pander and lie to him.? I will try to
remember that.
Investing $50 in a nanoVNA, to see if he even knows what
a VNA should do, or has any use for one, is foolish...
Far better to spend $3K to 10K only to find out he has no
interest, or need for a? VNA.?
Check. Got it.
-Chuck Harris
Your argument could be used any time someone asks about buying an oscilloscope, multimeter, or just about any other piece of test equipment. You can buy a cheap Chinese version and see if you want one.
The NanoVNA are supplied with a useless calibration kit, which does give people the illusion they are making decent measurements, when really they are not.
Your estimate of $3k-$10k is well off too.
The original poster should note that 4 N-N cables are needed to connect a test set to the VNA. You can make those up? yourself - they do NOT need to be phase matched, despite the original HP documentation saying they do. As long as the cables are stable, that's all that matters. The cable does not have to be anything special, as long as the screen is not so poor it leaks lots of RF.
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I think the 8753 models can be prone to LO failures but fortunately there are quite a few used spares available so it should be possible to keep one running. The CRT display can be swapped to LCD for some 8753 models as well if it gets a bit tired or fails.
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If you mainly want an HP VNA that also represents a 'piece of HP history' then the 8753 series is the classic choice. Of these, I prefer the models with the integrated test set (available with 8753D/E models) as this takes up less bench space.
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Be aware that the 8753D is a very heavy instrument, with its integrated test set and I recall that these things were a two person lift and you will need a very sturdy bench or trolley to put it on.
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The older 8753 models like the B and C will be lighter but they ideally require an external two port test set that sits below the analyser. I'm guessing the overall weight of the B/C and the external test set will be even more, but each of the two units will be easier for a single person lift.
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The later E(S) versions weigh just over 20kg even with the integrated test set. These are the most bench friendly. They generally offer the highest performance. Part of the weight saving is due to the LCD display. This display does look a bit gloomy and very dated but the ES is a very nice VNA. I used this model for many years at work.
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Due to advances in microprocessors, the processing speed (which affects sweep time) will be slower on the older 8753 models compared to the newer 8753 ones. This is most noticeable with all the internal error corrections running with a two port calibration.
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Due to advances in microprocessors, the processing speed (which affects sweep time) will be slower on the older 8753 models compared to the newer 8753 ones. This is most noticeable with all the internal error corrections running with a two port calibration.
Related to this, if someone does buy an 8753D, I would buy one with a 7.x firmware. These use a different and faster CPU to models with the 6.x firmware. The later firmware almost certainly has some extra functionality too.?
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I second the 7.x firmware version - which is probably why I'd stick to a D model or above.? As also stated, these models seem to have a propensity for source failures - my D model has the second one in it's lifetime, and it's in need of repair again... and it doesn't get used often.? Perhaps this is why they fail... I don't know.
That being said, Dr. David is also spot on about the cal standards.? The good thing is that you should also get a decent Nano VNA, and you can get surprisingly accurate readings from the Nano VNA with a good set of cal standards.? I compared my Nano VNA to my 8753D, and while it wasn't as accurate telling me which direction on the Smith Chart the load deviated from 50-J0, it was surprisingly accurate telling me how many milliunits off it was.? Note I write milliunits... while it wasn't as accurate, we're basically splitting hairs here in a way that any hobbyist would ever care about.? Once you're dealing with large deviations from 50-J0, it agreed quite readily with the 8753D in not only how far out from 50-J0 ohms, but where on the Smith Chart the impedance was.? This was using the same 85032B cal kit that I have for both the 8753D and the Nano VNA.??
From what I see, the newest top-of-the-line Nano VNA is superior to the original ones.? If you do go that route, be careful and make sure it's not a lower quality clone.
For sure, you will not be sorry with?both an 8753 and a Nano VNA.? And as far as the 8753 goes, get a D model with the latest firmware or above - having a color display and fast processor is key to getting a decent 8753 IMHO.? Just be sure to get a good cal kit no matter what you do.
I almost forgot to mention - for precision, the Nano VNA really needs to be run from the computer with - I think it's called - Nano VNA Saver.? This program lets you enter the cal standard polynomials/definitions so that you can get some meaningful precision from it.? At last check, the Nano VNA did not have a place to enter this info when running it standalone - but that might have changed in the last couple of years.
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Some years ago I started looking for a VNA and wanted to find the Agilent 8714ES (3 GHz) S-parameter vector network analyzer. Unfortunately that unit was selling for a king’s ransom at the time so I picked up a 8714ET vector network analyzer instead for a very reasonable price and in nearly new (low hours) condition.
But then the issue of a calibration kit came up. I ended up purchasing a new kit from Agilent for a price nearly equal to the analyzer itself (!!). A corresponding Agilent cable set was then found in lightly used condition for a very nice price.
In all I am very satisfied with the unit. It is very intuitive to operate and tells you if you are trying to do something that it disagrees with. For the average user either of the above units will serve as a nice machine depending upon their requirements. Obviously these units are normally somewhat pricey but as I found being patient proved to save a lot of money.
Greg
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On Sunday 20 October 2024 10:47:32 am Matt Harris wrote: From what I see, the newest top-of-the-line Nano VNA is superior to the original ones.? If you do go that route, be careful and make sure it's not a lower quality clone.
Where you buy it matters. There's a list on the nanovna groups io that lists recommended vendors, where you'll get the real thing and not a clone. I bought mine from R&L, along with some adapters and such. No connection other than I'm a satisfied customer. -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin
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One needs to be careful about NanoVNAs. There are a lot of clones out there. Most don't have the noise or return loss specs like the authentic product. The real NanoVNA website:
Some while ago I came across a NanoVNA site that seemed to be a fairly valid site (). But the info mentions that they use harmonics for the higher frequency measurement ranges. Their product also appears to have a higher noise floor. The drawback regarding the harmonic issue is explained in the earlier nanorfe.com site above who uses fundamental frequencies instead.
Another up-and-comer seems to be the LibreVNA that works out to 6 GHz. The developers site is (). He says it is still in a "work-in-progress" status. The board layout is impressive though. I looked into it a bit for my own use and my research has found while it's a good "hobbyist" level VNA it does suffer from heat issues. This in turn causes performance problems. Many users have circumvented this by building their own heatsink platform or underside fan arrays to mitigate thermal issues. Supposedly this problem is being addressed for the next generation on the unit. I haven't seen any news about a V3 release yet.
Greg
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Some quick notes regarding the NanoVNA versus a true Two-Port VNA that measures S11, S21, S12, and S22.? The NanoVNA is a very handy device, but there are some aspects of its operation that a user should keep in mind...
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1.? With the NanoVNA, there are different versions of firmware as well as application software.? They do not all use the same error-correction math, and some versions of this math could be more accurate than others.
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2.? Note that the NanoVNA Firmware (or App) will only correct S21 measurements for source-impedance errors (i.e. a deviation in Port 1's impedance from 50 ohms) if its error-correction math includes "enhanced response calibration" math (i.e. S21actual = ((S21measured - e30)/e10e32)*e10e01/(e11*S11measured - delta_e).
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3.? The NanoVNA error-correction math cannot correct for errors in Port 2's impedance.? The closer Port 2's impedance is to 50 ohms, the less of an issue this will be, but I don't know what the manufacturing variance of Port 2's impedance is, so this could be a "gotcha," depending upon the accuracy one might need.
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4.? Because Port 2's impedance cannot be corrected, S11 measurements of a 2-port network terminated with Port 2 can be in error.
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5.? Because the NanoVNA only measures S11 and S21, it cannot be used in situations that require the measurement of all four S-parameters (S11, S21, S12, and S22).? An example of this would be the calculation of "Operating Power Gain" (Gp), which is the ratio of the power delivered to a 2-port network's load divided by the power delivered to the network -- a very handy method of determining, say, power loss in an antenna tuner versus the tuner's load.
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- Jeff, k6jca
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On Sun, 20 Oct 2024 at 17:55, Roy J. Tellason, Sr. via <roy= [email protected]> wrote:
Where you buy it matters.? There's a list on the nanovna groups io that lists recommended vendors,? where you'll get the real thing and not a clone.? I bought mine from R&L,? along with some adapters and such.? No connection other than I'm a satisfied customer.
The word “clone” is talked of by a lot of nano VNA vendors. But they are all derived from an open source project. In typical Chinese fashion they?
1) Try to improve? 2) Copy each others improvements 3) Moan about others coping them.?
So there’s no guarantee that any particular design, which is being constantly changed, will be the best.
I had an early NanoVNA, but found the small screen too small. An 8753 has a bigger screen than any NanoVNA.?
Dave?
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There are Nano VNAs with 2.8" screens and others with 4" screens. Determining the best combination of authenticity, price/performance and screen size takes some research. The nanovna-users groups.io website has guidelines wrt to authenticity and "official" vendors. The other nanovna GIO websites may have similar guidelines. DaveD KC0WJN
Thanks for all the fish.
============================== All spelling mistakes are the responsibilty of the reader (Rick Renz, STK, ca. 1994) ==============================
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On Oct 20, 2024, at 15:48, Dr. David Kirkby, Kirkby Microwave Ltd via groups.io <drkirkby@...> wrote:
? On Sun, 20 Oct 2024 at 17:55, Roy J. Tellason, Sr. via <roy= [email protected]> wrote:
Where you buy it matters.? There's a list on the nanovna groups io that lists recommended vendors,? where you'll get the real thing and not a clone.? I bought mine from R&L,? along with some adapters and such.? No connection other than I'm a satisfied customer.
The word “clone” is talked of by a lot of nano VNA vendors. But they are all derived from an open source project. In typical Chinese fashion they?
1) Try to improve? 2) Copy each others improvements 3) Moan about others coping them.?
So there’s no guarantee that any particular design, which is being constantly changed, will be the best.
I had an early NanoVNA, but found the small screen too small. An 8753 has a bigger screen than any NanoVNA.?
Dave?
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Hello George,
?
I got involved with nanoVNA's back in 2019. ?At that time I purchased one of the original units from China, now called a "classic" model. ?I subsequently sold it and bought others and sold those as well. ?I finally settled on the DeepVNA 101. ?I like it for a number of reasons including the metal case, the rotary encoder and the bright display that works well outdoors. ?It truly suits my needs quite well for most of my projects and experiments.
?
My career in electronics was all in audio and video. ?Now that I'm retired, I started to teach myself about the other end of the spectrum. ?I got my amateur radio Extra class license back in 2007. ?I use my DeepVNA to learn about antennas and feed lines and filters and "spectral purity" issues. ?It's all great fun and I enjoy it a lot. ?And, like you, over the years I also have acquired a very nice collection of HP test gear. ?I even worked for the for a short while. ?But that's another story.
?
Some of the things that intrigued me about the nanoVNA were the reports (on this platform) from people who were paid, full time "RF Designers" and "RF Engineers". ?They made statements like, "I use an $nnnK VNA in my lab all day long. ?I bought a nanoVNA just to see how it would compare. ?I was pleasantly surprised by how well it worked and how accurate it was (in its intended frequency range) and at such a low price-point." ?Ultimately, this got me thinking that I too should purchase a "real" VNA (used of course) and do my own comparisons. ?So I started watching eBay.
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A couple of years ago I eventually found a used Agilent 8753ES with an 85046A S-parameter Test Set that was in my price range. ?I did my due diligence and bought it. ?It's now 25 years old, but it's still an amazing piece of hardware. ?I acquired it during the pandemic lockdown and had lots of time to study it, learn it and become fully acquainted with it. ?That's not a trivial task. ?Then I made the time to compare it to my DeepVNA. ?I came out of this work very pleasantly surprised myself. ?Yes, the DeepVNA would only go to a Gigahertz, or maybe a Gig-and-a-half if I pushed it. ?Yes, the 8753 would go to 3 GHz. but I don't do that much work up there. ?All-in-all, I concluded that the DeepVNA was a very practical investment, and I do not regret, and most likely never will regret, spending the money for BOTH of the VNA's. ?They are BOTH incredible TEACHING and LEARNING tools.
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Having said all that, pay attention to those who said "watch out for the CRT". ?They are known to get so dim as to be difficult to read. ?My Agilent unit has an LCD display and will most likely out-live me. ?Yes, there are kits to replace the CRT with an LCD unit. ?But do you really want to invest money in upgrading an older unit?
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Are they hard to repair? Any weak points on these units?
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In doing my homework, before buying the used unit, I determined that they are beyond my capability to repair, in both skill level and daring, not to mention the gear I would need to measure it or get it re-calibrated. ?I would most likely have to take it to Colorado Springs to get it fixed and that wouldn't be cheap for several reasons. ?And IMHO, the "weakest point" is the YIG Oscillator. ?My understanding is, you don't fix them, you replace them. ?And that's not cheap either. ?Still, I'm very much enjoying mine. ?One more thing: as far as Calibration Kits, Cables and Adapters go, there are GOOD and BAD, LOW COST and EXPENSIVE parts out there. ?Just what level of accuracy do you really need. ?I bought CHEAP and they work and I'm slowly upgrading. ?I'm not unhappy, but then again, I'm not a NIST subcontractor either.
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Good luck with your decision.
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Sincerely,
?
Larry?Goga, AE5CZ
Albuquerque, NM
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bownes
Dr. David Kirkby, Kirkby Microwave Ltd