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I was referring to hwalker's post in this thread on Apr 18, 2020. This is the link in that post:

I wish that Tindie or whoever sells official version would allow you to pre-order them so you knew you would get an official, non-clone copy, and they would simply build and send them in order of pre-orders received.

I certainly would prefer pre-ordering and having to wait then spending money and ending up with an inferior clone.

On Wednesday 17 February 2021 01:54:11 pm Roger Need via groups.io wrote:

On Wed, Feb 17, 2021 at 10:33 AM, Mark Adler wrote:

I received this same six-connector "NanoVNA Testboard Kit" with my VNA. Where
can I find documentation for this kit? The documentation link in this thread
is for a different two-connector test board.

The boards are very similar. I have not seen any documentation online for the six-connector board. What is different is that two additional sections have been added so that you can build attenuators, filters and test jigs with a 50 ohm microstrip. The documentation link above is a good guide to assembling the middle section. The 50ohm resistors are provided in case you need some for the microstrip section.

Roger

What are you referring to by "the documentation link above"...? I'm not seeing any link there.

--
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

Thank you for these videos.

For those of you who didn’t like my first two attempts at this video.. I think I’ve done a much better job on this one of explaining why I take my readings at 90 degrees phase angle on the smith chart

:-)

--
VE6WGM

Version 3



--
VE6WGM

Sorry, in color command need set full RGB index, for white color command

color 19 0xFFFFFF

On H4 this can be from default color on H4 for LC/Match (all colors can be changed by color command)
You need:
Run in console command for change LC match text color:

color 19 0xFFFF

and not fogot save CONFIG->SAVE

or reset all config

clearconfig 1234

For V2 - this bug come from how it output data on display, on button move not fully update, i can`t fix it fast

A video I did up last summer on how to use the nanoVNA to measure the resonant frequency of crystals.

The intended audience is those who are not wanting a complete and exhaustive characterization of crystals, rather, a quick and simple method to take a handful of random crystals and to determine the resonant frequency so as to be able to sort and label said crystals. Also includes a simple explanation of parallel and series resonant modes of crystals.



--
VE6WGM

Well, I'm an electrical engineer and I found it very useful.

Zack W9SZ

Hi !!
I find this that have the option to buy in EU.

is this genuine item??
I want my first nanoVna but buy from China take geological time for delivery.. but im also scared to buy a bad clones..
Mario

Hi,

Anyone have the trap LC values for a 6BTV antenna? I am building a model of it in 4NEC2.

--
73, and thanks,
Dave (NK7Z)

ARRL Volunteer Examiner
ARRL Technical Specialist, RFI
ARRL Asst. Director, NW Division, Technical Resources

On Wed, Feb 17, 2021 at 10:33 AM, Mark Adler wrote:

I received this same six-connector "NanoVNA Testboard Kit" with my VNA. Where
can I find documentation for this kit? The documentation link in this thread
is for a different two-connector test board.

The boards are very similar. I have not seen any documentation online for the six-connector board. What is different is that two additional sections have been added so that you can build attenuators, filters and test jigs with a 50 ohm microstrip. The documentation link above is a good guide to assembling the middle section. The 50ohm resistors are provided in case you need some for the microstrip section.

Roger

Raoul,

If you are interested in more info on measuring crystals with your NanoVNA I suggest the video by W2AEW on this subject. He carefully explains the terms and definitions and compares various testing methods. He has an extensive collection of videos and is well respected for the clarity and technical accuracy of what he presents. Quite a few recent ones deal with NanoVNA subjects.



Roger

I received this same six-connector "NanoVNA Testboard Kit" with my VNA. Where can I find documentation for this kit? The documentation link in this thread is for a different two-connector test board.

Great video, Gregg. Thanks very much.

73 de Raoul, CE3RY

This just became a bit more interesting.
It seems that there is a discrepancy in how
SimSmith calculates the angle depending on
the circuit block used. For an S block it shows
the same curve as in NanoVNA Saver and also
in Rogers graph (green trace).
But for a impedance block angle is different (red trace)
and much closer to the modeled resistor (blue trace).

[image: image.png]



On Wed, 17 Feb 2021 at 03:52, Dragan Milivojevic via groups.io
<d.milivojevic@...> wrote:

I guess that depends on what you consider as minimal
and if you are modeling an ideal resistor or a more
realistic one.

I guess that depends on what you consider as minimal
and if you are modeling an ideal resistor or a more
realistic one.

For example: on the first image is the plot of voltage
angle at the load (port 2 in this case), calculated from the
S21 file if the load is an ideal 50Ω.
The black trace is for a model of a 10K resistor with 50fF
of capacitance (reasonable value, according to Vishay for a
0805 capacitor) also into an ideal 50Ω.

[image: image.png]

The second image shows the same plot but this
time instead of an ideal 50Ω termination at port2,
I used the measured values for port2.
Not much of a change.

[image: image.png]

Last image is the port2 as measured, on a Smith chart (zoomed in quite a
bit).

[image: image.png]


Keep in mind that the calibration was done with
DIY "standards" and jig all made from cheap SMA
connectors from AliExpress, where the center
pin moves if you tighten the connectors enough.
DYT also from China with unknown properties.
Quite a sloopy setup.








On Tue, 16 Feb 2021 at 20:47, Roger Need via groups.io <sailtamarack=
[email protected]> wrote:

Dragan,

Thank you for clarifying what you did on your tests. I took a look at the
.s2p file that you posted and see that you get the same large S21 phase
shift that I got in my tests. I posted my plot of your S21 data below.
For a tiny SMD resistor like the one you used the phase shift should be
minimal (at least on the lower frequencies.). The S21 magnitude loss is
very close to what it should be for a 10K resistor but that phase shift
will give a lower R value and indicate reactance that isn't there if I
understand this correctly. Do you agree?

I also did a conversion from serial to parallel impedance and your S11
measurement was surprising close to 10K ohms. For a VNA designed for 50
ohm system impedance this was very good. Plot attached.

Roger

I would presume type 43 material is used?

For 160 and 80-meters your setup is quite reasonable. If you scanned to 30
MHz, likely a clean-up would be required, but you are aware of that.

Good work!

Dave - W?LEV

--
*Dave - W?LEV*
*Just Let Darwin Work*

Here’s what I did to measure the common mode attenuation of a current balun that I recently constructed.
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VE6WGM