VNA-nuts ? Show your VNA

[PA4TIM]

Very nice result.

Larry, I would like to see the same improvements like you but I do not think that will happen. I have asked Tom that a few months ago. The majority of the users seems to be  not interested in higher as 430 MHz but would have to pay more because some would like >1300 MHz. I think 3 GHz would be nice. But most user buy it because it is not much more expensive as a simple antenna analyser. There are users who used it higher, I'v seen sweeps upto 6 GHz but they used external hardware. One of the swedish guys, Dan, has used it on very high frequency with some extra external hardware.
Tom wrote an article about how you could do that. I still want to try that but to be honest, most of my use is under 10 MHz (1kHz to 10 MHz) for component behaviour measurement. But on serveral occasions I wiched it would go above 1500 MHz.

I measured a 23cm antenna for a friend. That is no problem. Mine is real good upto about 900 MHz, very usable with good cables and cal kit to 1300 and limited usable for a raw indication upto 1500 MHz but my V2.6A does not get that high.

I think you are talking about Kurt instead of Paul ? His last name sounds like Paul.

[kg4arn]

Thanks to all for an interesting thread.

A company in the USA is selling this unit:    http://arraysolutions.com/Products/VNAUHF.htm

Looks like about twice the cost.  Has anyone here heard of it or does anyone know how it compares to the SDR device?

[PA4TIM]

I have only read about it. It should have slightly higher dynamic range (according to what someone wrote me) , Software seems to be influenced by some agilent software. It goes from 300kHz upto 1300MHz and dynamic range also seem to drop above 600 Mhz.  As far as I know it can only do S11 and S21 (the VNWA can do S11, 12, 21, 22 and three port measurements (indirect, you have to switch connectors . The software tells you when and what to do, and  than does the rest as if it had 3 ports.

It looks nice with the N connectors but it is a rather high price difference. I think if it did 3 GHz for that price it could be a winner.

[PA4TIM]

This has been an analyser month. First I got 3 beautifull  calibrated coax cables with N connectors, then I received a SDR-Kits  Rosenberger sma callkit. Did some tests and that was a bigger positive difference as I would have thought. I allready had a homemade and amphenol calkit ,I Used the data delivered with the kit and made calibration from 10 kHz upto 1500 MHz and this improved as I hoped the response above 1GHz.

Today a General Radio collector came by to see my GR collection. He has a very big collection. As a supprise he had some GR goodies for me. Some GR874 adapters, some component fixtures, T- pieces, a krystaldiode modulator , GR adjustable capacitor for use on GR-874 and 3 Original shielded banana wires for my GR1603 and GR1620.
But the nicest thing was a beautifull wooden box with a GR1602 UHF/VHF 20MHz to 1500 MHz admitance meter. Including a short and a load. No I have to study the manuals. This is the grandmother of VNA's. I allready had the mixer/ detector , some unit oscillators, adjustable stub (but only the 50 cm), an other load, trombone and some airline. Only things still missing are the short adjustable stub, the GR-874 LK , the GR-874 LB balun and the 100 Ohm load. Now I have to learn to operate it.
I had no time for pictures yet.

[KD0CAC John]

Fred , just looked up your call on QRZ and see we got our tickets - ham license with about 1 yr. apart .
Wanted to thank you ham related VNA website , it makes more sense to look at them from a ham perspective for me ,
doing self talk about all these toys , I picked up a miniVAN Pro recently and it helps to get a handhold on all the RF values and understand .
Now if there is enough yrs. left to get good at it

[DL8RI]

Anyway, here's some of it. Top down:
 HP 8405A   vector voltmeter,
 HP 8418A   aux display holder, with 8414A polar display (also have the 8413A  Phase-gain meter)
 HP 8410B   Mainframe, with 8412B   Scope (rectilinear)
 HP 8411A   Harmonic freq converter
 HP 436A    Power meter (also have some assorted sense heads)
 HP 8750A  Storage normalizer (not sure I have the right interface card and cables for this and the 8410B)
 HP 8743A  Trans/Refl TS  (2-12.4GHz)
 (and a bunch of other stuff elsewhere

Nice to see someone using this stuff today.
I scrapped two of this VNAs recently (didn't have the room for such a "spacy" unit at that time ). If you ever need spare-parts, write me a PM I ripped some stuff out of the generators.

[PA4TIM]

Admittance measurement in 50's pre-vna style. It can do 10 MHz to 1500 MHz but I can only use it to 450 MHz because I do not have the sliding short that is used as suseptance standard.

[joeqsmith]

Some pretty neat looking antique equipment posted here.    I have an old HP3589A w/o the S-parameter set.   My other one is a real old HP8754A. 

The following video shows my 8754A in action.   

[PA4TIM]

That is a nice VNA set you have there. I love your collection of cal kit pcb's. I soldered capacitors straight on sma connectors but that gave mechanical problems. The capacitors broke because the centrepin moves a tiny bit while mounting it on the analyser. Dit you buy those pcbs somewhere or made them yourself ? Nice software too. It is very impressive the way yours measures such a small capacitance.

By the way, double sided pcb is great for making capacitance standards, you can easy trim then by changing the size with a file. I have made a some this way (10pF upto 100 pF). Soldered a piece of 1mm silverplated wire to each side and use them to test LCR meters. (calibrated them with a GR1620. Mine is Ex-GR and was used in GR's own standards lab)

In your video you are testing a probe. I have done the same thing a few years ago.  Did you measure the probe while it was  connected to the scope input ? I found out recently that makes a difference. (I read something about input capacitance of a probe in some pdf, but can not remember where or what. It was not about testing probes but they needed that value for something related to the testing. I forgot about it until a friend asked something about probe capacitance and I put an LCR meter to the tip. It was still on the scope. I then remembered I read about this and disconnected the probe to see if there was a difference, and there was.

I now finaly have another stone age impedance measure instrument. A GR 900 slottedline including cal kit and a bunch of GR-900 adapters, amongst others for GR-900 to bnc, sma, N.
Also found the adjustable stub for the GR admittance meter.

http://www.pa4tim.nl/?p=4978 for the slotted line



http://www.pa4tim.nl/?p=3059 my probe test, it is still in Dutch but has a lot of photo's and pictures

[KJDS]

I picked up an HP8510 a few weeks ago, still need to find a signal source for it.

[Howardlong]

I am a marketing guy.

Cue tumbleweed...   

http://youtu.be/iIIuR-HjFho

Sorry, couldn't resist!