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Wrong one.
He wants these:

Here:
,searchweb201602_2,searchweb201603_55


Expensive...

On Thu, 5 Sep 2019 at 18:16, Barry via Groups.Io <boat.anchor=
[email protected]> wrote:

On Thu, Sep 5, 2019 at 09:38 AM, George wrote:

Just noticed that the connectors are fastened to the case. See photo.
I have been worried about damaging them from too much torque.
This connector problem, that some are experiencing or worrying about,

may have

been solved.

Also notice in the photo, the RF demo kit. Might be useful for

beginners and

even seasoned pros.

I was interested in the RF Demo kit and I have searched inet for
RF Demokit for Nanovna by WWW.SYSJOINT.COM to no avail.
Where might I locate one?
TIA
Barry

On Thu, Sep 5, 2019 at 09:38 AM, George wrote:

Just noticed that the connectors are fastened to the case. See photo.
I have been worried about damaging them from too much torque.
This connector problem, that some are experiencing or worrying about, may have
been solved.

Also notice in the photo, the RF demo kit. Might be useful for beginners and
even seasoned pros.

I was interested in the RF Demo kit and I have searched inet for
RF Demokit for Nanovna by WWW.SYSJOINT.COM to no avail.
Where might I locate one?
TIA
Barry

Forgot to push the Add button

Well, at my age I can not read the NanoVNA screen so I alway use a PC application and the NanoVNA only does the raw signal processing only
The PC application does the rest, calibration, display, export, math etc...

Just noticed that the connectors are fastened to the case. See photo.
I have been worried about damaging them from too much torque.
This connector problem, that some are experiencing or worrying about, may have been solved.

Also notice in the photo, the RF demo kit. Might be useful for beginners and even seasoned pros.

That does sound very useful! A couple of zeroes more and a header, and
you'd be outputting an S2P file. :-)

--
Rune / 5Q5R

I agree 100% with the idea of using connector savers. When I sold for HP we always recommended it as it would cost thousands of $$ and lots of lost time to replace a connector on their VNAs. A simple connector saver costs little.



As for what to use, completely up to you. SMA male (to mate with nanovna) to whatever connector you most often use. Buy 2....or 4 (spares) and you're good to go.?



RE: Calibration. I recall reading a post suggesting doing a cal across the full span the nanovna covers. I'd think it would be better to cal just over the frequency span you intend to measure. With the limit of 101 measurement points I'd think this would give a more accurate cal.


Sent using




---- On Thu, 05 Sep 2019 12:12:49 -0400 SPACE OPQA <spaceopqa@...> wrote ----


Hello,

What was your solution for sacrificial connector?

Most of my devices are bnc/UHF connectors, so maybe sma to bnc?

Cheers!

On Thu, Sep 5, 2019 at 11:54 AM Dr. David Kirkby wrote:

In my opinion, BNC would be a complete disaster

Fair enough. What I might better have written:
* All my measurements employ pigtails which remain connected to nanoVNA.
* Most of my DUTs use BNC; I "calibrate" using an old generic 50 Ohm
BNC terminator...
* Others should presumably use pigtails with connectors (and
calibration kits) matching their DUTs.

IMO, calibrating with one connector type for measurements with another
seems problematic.

I added one command to the eddy firmware to enable on demand scans of arbitrary length (yes, you can scan with one million steps or much more if you want)

Usage:
First pause the continuous scanning with "pause" and the use the "scan" command to scan [from frequency in Hz] [increment frequency in Hz] [number of steps]
The frequency increment step is for now an integer
The scan command outputs

start
frequency s11_real s11_imag s21_real s21_imag
done

during the scan the calibration is NOT used so the output are uncalibrated numbers allowing alternative calibration strategies

Example:
ch> pause
ch> scan 5000000 20 5
ch> start
5000000 0.001503840 0.000420701 -0.306770563 0.018568072
5000020 0.000695601 0.000503197 -0.306792527 0.018579231
5000040 0.000532656 0.000520238 -0.306793421 0.018573865
5000060 0.000495833 0.000512704 -0.306819111 0.018593480
5000080 0.000520689 0.000523833 -0.306812644 0.018576323
done

ch>


For the paranoid, the source is available on:

Does anyone know of an output gated 16 bit integer complex to real FFT code? That would substantially reduce the amount of space required to do TDR on the stock nanoVNA.

While the FFT is fundamentally just reordering operations so that the additions are done before the multiplications, they do get fairly complicated. I'd prefer not to write one from scratch if I can avoid it. And there are a lot of FFT codes out there. And lots of tutorials any of which may or may not discuss gating the output. So it's a serious time sink to search for one.

Without output gating, a 1 microsecond TDR trace will require 8 KB of RAM for 500 ps resolution. I don't see a way to get below needing 3.6 KB for the frequency domain magnitude and phase. The sample spacing in frequency is what governs the maximum time of the TDR trace whether you gate the output or not.

Reg

Just saw it on ebay for US$139 plus free shipping.

"NanoVNA VNA HF VHF UHF Vector Network Antenna Analyzer + 4.3 inch IPS LCD + Metal Case + 5000mAh Battery"



I like the longer battery life, the nice looking case and other features. There may be one in my future.

Many thanks, Hugen!

- Jeff

M2.5

I'm not familiar with metric screw sizes. Can anyone tell me the diameter (e.g. M2 or...?) of the screws used to hold the NanoVNA covers to the PCB?

Thanks,

- Jeff, k6jca

Thank you Rune for this information. I will try this again. Bob

Hello,

What was your solution for sacrificial connector?

Most of my devices are bnc/UHF connectors, so maybe sma to bnc?

Cheers!

Yes, not easy. Takes patience.
Again I recommend connector savers to be attached to the VNA SMA's. Do that once and no need to touch that interface again until the saver goes bad.

On the SMA as to the pin rotation. The trick is to keep the body of the connector from moving. The pin joins the body. The NUT only would SPIN and draws the pin straight into the connector. Again, the SMA spin nut does assist a bit in that task.

On larger connectors this is all much easier but with a little patience it can be done with the SMA.

Alan

hugen,

I sent a private reply asking to get the regular nanoVNA with a '303 part substituted for the '072 part but never received a reply.

For the moment I don't care about the screen size. I just need a development system.

As others are likely to want one, just tell us how to buy one.

Thanks,
Reg

Karl,

I used a 602040 450mAH (5x20x31.5mm) battery in my Banggood NanoVNA. I don't think anything bigger will fit.
$8.99 from Amazon.

Ken
KF7DUR