[NLRS] NLRS Breakfast - last show-n-tell

[Doug Reed]

I brought the NanoVNA. They showed up on Ebay and I decided to buy one
to see what it looked like. They all seem to start in the $80 and up
range. There are white and black models, I think the black is slightly
newer. As always with Ebay, you have multiple vendors selling newer
and older models of the same product, so do some reading to see if you
can choose a later model. As you saw and Donn commented, the whole
unit is tiny (credit-card size) and the display is also tiny and hard
to read unless you have very good eyes, or are near-sighted without
glasses. :-)

It looked to me that all the vendors sold basically the same kit with
the NanoVNA, two 12" SMA cables (RG174?), one double-female SMA
adapter, and three SMA males for OSL calibration. The charging cable
is a newer USB Type-C cable. It doesn't come with anything resembling
instructions, but there are a few web sites starting to show info
about the units and you can find the original (?) info by searching
for "github nanovna" or use this link
<https://github.com/ttrftech/NanoVNA>. The next step would be to join
the Groups.io NanoVNA group for support and update info. And they did
a simple (Getting Started level) user manual
<https://groups.io/g/nanovna-users/attachment/14/0/NanoVNA%20User%20Guide_20190527..pdf>.

You *WILL* need to buy a small point touch-screen stylus to make it
easier to change settings on the NanoVNA. I'm not sure I trust the
RG174(?) coax jumpers they supplied because I've seen instability in
readings due to foam dielectric in the past. Solid poly isn't bad, but
Teflon dielectric is more stable, so you might need to buy a couple
Teflon SMA jumper cables on Ebay. I also bought about $40 of assorted
cheap SMA to N, BNC, & UHF connectors to mostly complete the test kit.
The remaining annoyance is the fact that the edges of the front, back,
and PCB panels are exposed all around the edges. I was joking once
before about maybe a big rubber band would close the edge, but perhaps
someone will eventually 3D-print edges for the case.... So far I have
everything I mentioned stored in a plastic case for 3x5 index cards.

One of the blogs I read about the NanoVNA was very negative and
disappointed that a product using a 0-200MHz oscillator was
advertising a 900MHz operating range. I believe its all done with
harmonics and a lot of math. The same person seemed upset that it
didn't have full RF specs up to 900MHz, but I specifically read about
the lowered dynamic range as you go higher in frequency and I decided
I can live with it. As far as I'm concerned, it will still have more
dynamic range than I need for measuring any antenna, RX front-end, or
single cavity I'll ever see. No, it will not read a duplexor rejection
notch 100dB down, but very few pieces of equipment will....

I'll let you do the rest of the research yourself....

73, Doug Reed, N0NAS.


On 8/19/19, Don Huettl <dahuettl at gmail.com> wrote:
> Donn and Doug brought network analyzer show-n-tell hardware to the Golden
> Corral. Are there any Internet links to the items?
> -Thanks, Don H. - K0AH
> ______________________________________________________________
> NLRS mailing list
> Home: http://mailman.qth.net/mailman/listinfo/nlrs
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:NLRS at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>


-- 
Growing old is compulsory, growing up is optional!

When I was a kid I wanted to be older.... This is not what I expected.