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Hello i have tried it on lots of other antennas, the only way i can describe it is on the smith chart to the right of the chart its just a swirling mess of lines, on the swr mode just lots of up and down lines very odd

On 9/1/20 7:45 AM, Larry Rothman wrote:

Anything transmitting nearby?
/g/nanovna-users/message/14777
Verify the Nano works on a different antenna that is physically away from the one you're having issues with. How is it with an ant from a portable?

Do you get a good sweep on the load (i.e. VSWR=1:1 or Smith Chart is a dot)?

if you happen to have a known mismatch (two 50 ohm loads in parallel with a T is convenient) you can try that as a check, as well.

Anything transmitting nearby?
/g/nanovna-users/message/14777
Verify the Nano works on a different antenna that is physically away from the one you're having issues with. How is it with an ant from a portable?

Hello Larry

Yes pressing reset each time
Cables are good
Tested the 50 ohm load and still good

Thanks David

Are you pressing the RESET menu button prior to calibrating?
Have you verified the cables you use to calibrate are not defective in any way?
Have you verified the 50 ohm calibration load is still good?

Hello, everyone, I was hoping that someone may be able to help.

Been using my VNA for weeks working on tuning an Antenna then suddenly yesterday things when a bit haywire.

With nothing attached the SWR is maxed out and on the smiths chart it's constantly changing. then after many many calibrations doing it the correct way, I attache the antenna, rather than a curve to represent the SWR just a load of lines going up and down and never settling constantly moving any ideas

Thanks, David

At least if you are going to nitpick do it correctly

1 mHz (millihertz) = 0.001 Hertz and I doubt you would be able to hear it

During 50 years in engineering errors like that creep in..

Often its minor and the context makes it clear it only a typo...
but once while presenting a technical subject in computer
science to fellow engineers I had a person interrupt to
point out and ask me to correct and obvious typo I'd missed.

it was hTe... oops. The...

The effect was so jarring while I was explaining a complex timing
and decoding issue that it blew my entire train of thought and
proceeded to correct it since I had the system to do it. Then I
stood there the first three minutes was awkward as I tried to
remember the point and it was incidental to the slide. I finally
asked if someone could help me with what I was saying and
they all looked at the corrector expecting him to know, he didn't
as he was all wrapped up in "hTe" and not the subject. Thankfully
someone else did and I was able recover the thought and resume.

The point being sometimes its important, occasionally its helpful,
but it can be totally disruptive.

Allison
-----------------
No direct email, it goes to bit bucket due address harvesting in groups.IO

It perhaps should have been obvious, but I recently realized that Electrical Delay can be used with the firmware TDR to allow high time resolution even on longer cables. A wide frequency sweep provides good time resolution, but limited time display range on the screen. Setting the Electrical Delay parameter can move that limited range window out in time to provide good resolution at the end of a longer cable.
Here is an updated version of my earlier setup procedure:

The following setup for the NanaVNA-H, -H4, or -V2 will give a display much
like that on a conventional TDR such as the Tektronix 1502:

Set stimulus for a wide sweep, say 50kHz - 900MHz or more.
Do an SOLT calibration at the desired measurement point (if not already done)
Set TRACE 0 for Real format
Turn TRACE 1 off
Set TRACE 2 for Smith,
Turn TRACE 3 off
Turn TRANSFORM ON
Select Transform LOW PASS STEP
Adjust ELECTRICAL DELAY to move the displayed window to the desired location along the cable

The resulting display should be similar to that on a step-type TDR like the
Tek 1502. With 900MHz max, the display width is about 43ns, with 3GHz it is about
8ns.
Impedance along any connected cable can be read by moving the marker to the
desired time (distance) and looking at the Smith chart marker values. You need to mentally add the
ELECTRICAL DELAY to the marker time to get the actual delay.

Save via the CAL menu when you have it all set up.

An open cable will show as an initial middle value depending on the cable
impedance followed by a step up. A shorted cable will have a step down. A
properly terminated cable will just be a steady middle value.

Dave VE3LHO, what you wrote is exactly what I planned to do: use the UART pins, available on PCB 3.4 of my nanoVNA-H and connect them to HC-05 BT module, in order to use my laptop to interact wireless with nanoVNA.

However, the problem that I have is to get a firmware that set and use the UART instead of the USB port.? I am looking for someone that would like to issue a modified version of the firmware.

Best regards

Piero, I0KPT

Il 31/08/2020 22:31, Dave VE3LHO wrote:

Sorry group;
It was operator error in entering commands. Now everything is back in business.
John

I think you all are making it more complicated then it needs to be. Or maybe trying to simplfy in a way that the OP doesn't intend to consider and which probably isn't really a simplification.

Either way the nanoVNA-H v3.4 pcb does have a uart (rx/tx plus Vcc/Gnd) brought out to a header. See the schematic here:
Approrpiate header seems to be P3.

That would then be connected to the coresponding pins on the HC05. Well I assume you may need to attach Tx to Rx and Rx to Tx between the two.

The OP is just looking for FW which connects the serial console to this (real) serial port rather than the (virtual) serial port across the USB. No funky USB devices or extenders or ...

As for BLE and incompatible variants of BT: maybe all true but no one says the OP is going to use a smartphone. In fact a laptop would probably make a better choice. In my experience this should work without too many hitches for a simple serial over BT link even with oldish BT 2.x devices like an HC05

And WRT:

Personally - I am curious why developers spent time building bigger, more
expensive and less portable displays when adding bluetooth would let user to
use ANY size of REMOTE display for few dollars.

Hmmm because a bunch of people want a bigger display, full stop? They don't want remote. They don't want TWO pieces of equipment, just one.
If a bigger display is the issue for someone then the option already exists to use another device through the usb cable. But many people want a bigger display and a single piece of equipment.Enough people to make it a viable product, I guess,
Others may want remote operation but that seems to be a smaller number. I believe the serial uart pinout on the v3.4 pcb was to allow those folks an option.


On Mon, Aug 31, 2020 at 10:01 AM, Anne Ranch wrote:

Bluetooth technology is one of the most poorly documented "stuff" around.
A techno geek will tell you it is all based on "bluez" library which is
prime example of how such simple and undocumented library gets blindly passed
to many "sophisticated" software application, including IDE and OS. It is
allegedly included in Linux "core".

The main problem with bluetooth, in MY opinion , there are options, quite a
few of them - both software and hardware.

Which one to pick really depends on SPECIFIC application - nothing new about
that concept.

On my PC , I am using

Cambridge Silicon Radio, Ltd Bluetooth Dongle (HCI mode)

as generic bluetooth device with USB interface , roughly $5 item.

Works fine accessing CAT port on FT-857, using chirp software
work fine with NanoVNA-SAVER

On my FT-857 I have "serial to bluetooth " device - work fine, maybe HC5 would
work too.


In theory , any USB / bluetooth device should be able to be connected to
NanoVNA USB port - via proper adapter.

Of course NanoVNA firmware WITH bluetooth / USB option MAY be on some
developer's work list.

Personally - I am curious why developers spent time building bigger, more
expensive and less portable displays when adding bluetooth would let user to
use ANY size of REMOTE display for few dollars.
( No , I am not interested in writing the software , got my own projects)

For some reason the picture was not loaded to my last message. Here is a link....


Roger

On Mon, Aug 31, 2020 at 03:34 AM, Piero Tognolatti wrote:

Taking advantage of an advice from One-of-Eleven, I have purchased a
Bluetooth module HC5 that I would like connect to my nanoVNA-H (PCB 3.4)
in order to remotely control it. As you probably remember, I have to
measure antenna input impedance on a mockup of a 3U cubesat and I cannot
have any metallic cable coming out from the satellite mokup.

Does someone know if I can find a proper version of nanoVNA-H firmware
that already allows to interface, via Bluetooth, a nanoVNA to any
software running on PC?

The picture below shows the internals of the NanoVNA-H PCB3.4 which has the serial pinouts which could connect to a serial Bluetooth HC05 module. Unfortunately no one has developed any firmware which they are publicly sharing that supports these serial pins or a serial Bluetooth module.

This Bluetooth capability is available on other analyzers like the one port VNA's from RigExpert so it can be done.

Roger

On 2020-08-31, at 20:27, David Eckhardt <davearea51a@...> wrote:

mhz = millihertz or 10E-3 Hertz (1000 Hz - audio)

As Gert said, mHz, and, as you said, 0.001 Hz.

Also, 1 mHz = 1E-3 Hz or 10^-3 or 10?? Hz, not 10E-3 Hz...

But seriously, getting details like the unit names right is a signal of competence.
Frankly, why should I trust an instrument the designer of which didn’t even care to use the proper unit names?
So I think this is actually more important than it might at first seem.

Grü?e, Carsten

Shouldn't it be mHz ? Just like MHz.

Case sensitivity *does* matter!!!! grin Grin
Don't remember how often i made this mistake too.

Gert

--
Independent Expert on CE marking
EMC Consultant
Electrical Safety Consultant

On 8/31/20 10:01 AM, Anne Ranch wrote:

Bluetooth technology is one of the most poorly documented "stuff" around.

And inconsistently implemented.

The main problem with bluetooth, in MY opinion , there are options, quite a few of them - both software and hardware.

There's also a HUGE difference between "compliance testing" according to the standard and "make it work". Unfortunately the owners of the standard/trademark have never really cracked down on non-compliant devices.

Which one to pick really depends on SPECIFIC application - nothing new about that concept.
On my PC , I am using
Cambridge Silicon Radio, Ltd Bluetooth Dongle (HCI mode)
as generic bluetooth device with USB interface , roughly $5 item.
Works fine accessing CAT port on FT-857, using chirp software
work fine with NanoVNA-SAVER
On my FT-857 I have "serial to bluetooth " device - work fine, maybe HC5 would work too.
In theory , any USB / bluetooth device should be able to be connected to NanoVNA USB port - via proper adapter.

The tricky part is that the NanoVNA is expecting to see a USB "host", while a lot of BT devices are USB "devices".


Then, there's the whole USB "can be either a host or a device", particularly with USB-C and power transfer.

Of course NanoVNA firmware WITH bluetooth / USB option MAY be on some developer's work list.
Personally - I am curious why developers spent time building bigger, more expensive and less portable displays when adding bluetooth would let user to use ANY size of REMOTE display for few dollars.
( No , I am not interested in writing the software , got my own projects)

Standalone device development (firmware for such devices) is easier to validate. You're not dependent on the (not entirely well documented) behavior of the external device.

I think the ultimate solution will be something like the NanoVNA (which does the measuring) combined with an Arduino, Beagle, or Pi (which does the instrument management and provides a more sophisticated UI).

That way, VNA developers can focus on instrument performance, and provide a set of basic functionality "on the device" having to do with calibration, etc. And the ability to display as a standalone device.
But then, if you had a larger device (tablet, PC, what have you) it could have software that would interact with the NanoVNA.

Conceiveably, for instance, one could write Java code for Android (or whatever is appropriate for iOS) that would talk to the NanoVNA over the existing "emulate a serial port" interface. The tablet/phone/computer is the "USB host".

Yep! They beat up on me as well in college.

Now we at LTO try to get our STEM students to properly utilize 'scientific
notation'. I was using it in the fifth grade..........but today, even
high schoolers can't seem to grasp the standard engineering notations.

Dave - W?LEV

On Mon, Aug 31, 2020 at 6:34 PM Roger Stierman via groups.io <rogerstierman=
[email protected]> wrote:

Tell me about it. This was the only translation mistake I made when i
translated all those Russian conference proceedings in grad school (early
1980's; US-USSR relations meant NOBODY ELSE had those proceedings at the
time!). I was used to nuclear reactions (MeV strength); had never run into
someone using milli eV (meV) for chemical reactions.

Learned a lot in grad school. Still remember it.


Best Regards,
Roger WA0VYU

On 8/31/2020 1:27 PM, David Eckhardt wrote:

This may be a nit pick to some, but for those of us who learned
(correctly) that uppercase = M = Mega = 10^6 and lower case = m = milli =
10^-3, the following:

mhz = millihertz or 10E-3 Hertz (1000 Hz - audio)
MHz = Megahertz or 10E+6 Hertz (1,000,000 Hz - middle of
the BC Band - RF)

Case sensitivity *does* matter!!!!

Dave - W?LEV

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

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

OOOps: mhz =millihertz or 10E-3 Hertz (0.001 Hz or subsonic)

Dave - W?LEV

On Mon, Aug 31, 2020 at 6:27 PM David Eckhardt via groups.io <davearea51a=
[email protected]> wrote:

This may be a nit pick to some, but for those of us who learned
(correctly) that uppercase = M = Mega = 10^6 and lower case = m = milli =
10^-3, the following:

mhz = millihertz or 10E-3 Hertz (1000 Hz - audio)
MHz = Megahertz or 10E+6 Hertz (1,000,000 Hz - middle of
the BC Band - RF)

Case sensitivity *does* matter!!!!

Dave - W?LEV

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

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

This may be a nit pick to some, but for those of us who learned (correctly)
that uppercase = M = Mega = 10^6 and lower case = m = milli = 10^-3, the
following:

mhz = millihertz or 10E-3 Hertz (1000 Hz - audio)
MHz = Megahertz or 10E+6 Hertz (1,000,000 Hz - middle of
the BC Band - RF)

Case sensitivity *does* matter!!!!

Dave - W?LEV

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