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Ask Owo on discord channel (Elon Musk#0678) for bootloader and instructions if need

Here is instruction


Read all. You need ST-Link, need get correct bootloader for device s/n. Replace elements. Flash bootloader. Flash Plus firmware.

Hi Alan,

I'm afraid I've never connected the device to a PC (!), and there is no Reset command in the device's menu tree.

Dave

Hi Dave,

Did you execute the RESET command prior to any cal?

I have the same antique and a one port only device and to date, zero issues.

Alan

Hello DiSlord,

In this message I read that you have modified the V2 to V2plus.

I hope you don't mind my asking, can you please give me some info about this modfication or where to find it.

Thanks in advance,

Jos

Op 11-2-2021 om 21:32 schreef DiSlord:

Have you seen these instructions yet? Other models access DFU another way.

This is the original nanovna I purchased (after which I started [email protected]) in May 2019. The firmware is as was shipped/delivered, never updated (although I started the group and have enjoyed the many discussions since then, I've had little time to use the device.

Question is this - after SOLT calibration at the female device port (no jumper except for the thru test, using the O S L parts that were delivered with this nanovna device in mid 2019), reflection loss S11 with open port does not match expectation.

Frequency limits set to 1 and 100 MHz, followed by OSLT calibration at the device ports. Repeated this to reduce chance of operator error. The standards are those that were shipped with the nanovna in 2019. Device is running with it's internal (original) battery, fully charged.

With port open, S11 shows 7.5 dB (not ~0 dB; starts at 7.50 dB ends at 7.53 dB) across the frequency range (visible both with logmag and smith chart formats.)

With port shorted, S11 is ~0 dB across the frequency range.

With port terminated, S11 is ~-80 dB across the frequency range.

Transmission loss (S21) is < 0.5 dB across the frequency range (0.2 to 0.5 dB).

I do not recall seeing S11 with open port of this nature in the past, although again I've made little use of the unit since new.

Am I doing something wrong? Does this seem like a device issue?

Thanks,

Dave

This is driving me nuts, sine I have the firmware version 0.0.5, I am having a hard time trying to figure out the firmware update process. First off there is no CONFIG tab on the screen when you first bring it up. Am I missing something totally ? The beginners guide shows it but I don't have it.. Can I get a shove in the right direction ?

Thanks
--
Bob Lukaszewski K4HA

One side of the window line goes to the beverage wire. Where does the
second wire of the window line go?

At the VNA end of the window line I would presume the window line wire that
connects to the beverage connects to the center pin of CH0. And the other
wire of the window line at the VNA connects to the VNA chassis or backshell
of the CH0 connector. Where does that second wire of the window line
ultimately connect when you are using the beverage?

To make a measurement, do not hold onto the VNA, but set it on a stump or
empty box well above the soil surface. If all this is the case, the window
line single wire connected to the beverage is just an extension of the
beverage. It has no return at the feed end. The non-beverage connected
wire of the window line should go to some sort of return, like a ground
stake.

Dave - W?LEV

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

I use Anritsu Site Master S810D for comparsion
For calibration use it calibration kit
Measure SWR 2.0 standart
Foto from:
Anritsu Site Master S810D
V2Plus (modded from V2)
H4 (it have very clean measure, but little lost dynamic after 900MHz)
V2Plus4 (good measure)
Jankae VNA2

Dave NU8A,

Thanks for taking the time to write your post. Your explanation was concise and well done.

Roger

Hello, can someone send me fm9688 chip? I know it can ordered from china, but there is new year season...Maybe from europe etc..pay via paypal--73 oh2lir

Dave, NU8A, and Jim Lux, thanks for filling in where I am unable. I do
detect a very slight difference connecting both conductors vs. measuring
only a single conductor, but your explanation makes it clear why. BTW:
The impedance of my lines on the toroids is between 80 and 100 ohms.
Fortunately, I have a good supply of carbon resistors to 'experiment' in
that respect. The line impedance is lower with the Teflon coated
conductor than with the DavisRF 'antenna' wire,likely due to closer
conductor spacing.

Again, thank you both for your inputs. Life should be a continuous
learning process! These NANO groups are great in that respect.

Dave - W?LEV

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

The DM loss is primarily due to mismatch loss between the 50-ohm source impedance and impedance transformation caused by the bifilar pair behaving as a transmission line. The bifilar pair used here probably has a transmission line characteristic impedance of something around 100-120 ohms. If you take the bifilar pair by itself without any ferrite, and connect it between NanoVNA the ports, the DM loss measurement should be nearly the same as measurements made with the ferrite. What you see is impedance mismatch loss.

Here's the reason the ferrite has negligible effect with a differential signal. For all practical purposes, the magnetic fields around each wire in the bifilar pair are equal and opposite because the current in each wire is equal and opposite in differential mode. This makes the magnetic fields cancel and there's nothing left to interact with the ferrite.

So why does the mismatch loss go up with frequency? Because as the frequency goes up, the length of the bifilar pair as a transmission line increases in terms of wavelength. As this happens, the bifilar pair progressively transforms the load impedance seen at the source. As it moves away from 50 ohms, the mismatch loss increases. Maximum impedance transformation (and therefore maximum mismatch loss) happens at the frequency where the bifilar pair is a quarter wavelength long. (Making a few guesses about the length and characteristics of the bifilar pair, I estimate the max mismatch loss happens around 70 MHz with an impedance seen at the source of about 290 ohms.) If the frequency is raised further, the mismatch loss starts going down as the transformed impedance circles back to 50 ohms! Mismatch loss would be lowest at the frequency where the bifilar pair was now a half wavelength and the NanoVNA source port would see 50 ohms. (Of course there's no intention of using these particular chokes at VHF frequencies, this is just a way of explaining what's happening with the measurement.)

Dave NU8A

P.S. Purists may want to discuss parasitic reactances, incomplete field cancellation, and transmission line loss, but those effects will not significantly change the primary cause of the measured DM loss at HF frequencies with these chokes.

Using VSWR or Return loss is a practical idea to avoid the dynamic range
issue. Connect a 50 load to both the antenna port and the opposite input.
Connect the NanoVNA to the input port of the duplexer with the NanoVNA set
to S11 with either both or either VSWR or Return loss.the VSWR or Return
loss will increase at the point of the resonance or notch. I use this
method more than the through method. Of course once tuned you can use the
through method to determine the loss at the pass frequency.

I was also thinking about using a low noise broadband amplifier as stated
by W8LM.


*Clyde K. Spencer*



On Thu, Feb 11, 2021 at 11:13 AM Larry Macionski via groups.io <am_fm_radio=
[email protected]> wrote:

55 years as a ham, and years ago, hams made due with what they had and all
they had to tune duplexers was it's transmitter and receiver, a step
attenuator, another 2way radio, Dummy loads and a good VOM. There is a
procedure to do it like hat in an old ARRL Repeater Handbook Circa 1980.

Last January I tuned a old pair of WACO duplexers. with my NanoVNA. All
fine since. Since you have no experience... CHECK the duplexers 1st before
you start screwing around. READ up on everything on repeaters. Go to this
site and download the white paper on "ANTENNA DUPLEXERS".. Print it and
read it twice.



EMR is one of the oldest, most trusted in the business.. The Founder was a
ham and knew his stuff..

A setup to check --NOTE CHECK--- a duplexer.. #1. carefully calibrate
NanoVNA for 3-4 megs around the frequencies of interest. Rough pictorial
but you should get the drift of how to connect.

------------------ ch0
NanoVNA ch1-------------------------
|
|

------------------CAN-------CAN------CAN--------------- |

CAN CAN CAN | |

CAN CAN CAN | |

+-----------

|

|
50 OHM DUMMY LOAD
------------------CAN-------CAN------CAN---------------

CAN CAN CAN

CAN CAN CAN

Set your marker frequencies for repeater input and output frequencies
set display to make 2-3 passes 101 points X3..... as the plot bottoms out,
at -50- -60 dB, the curve will get ragged there. You want the marker to be
in the middle of the ragged area. I have not tried it yet, but I did buy a
$5-10 20dB 0-2Ghz broad band amplifier, to install in the CH0 line to see
if I can "raise" the plot to more accurately adjust the notch. Think of
CH0 as a transmitter and CH1 as a receiver.
I also used this setup to measure SWR at inputs.
Swapping CH0 with the dummy load, will test both sides of the duplexer...

I used VNA saver as you can increase the number of points on a plot to
X8.. all thought the sweep is slower. You can save your plots to a file or
print them out. more practical than the NanoVNA alone.

Larry W8LM

I found 2 of my plots,,done with a NanoVNA 144.76 -145.27

55 years as a ham, and years ago, hams made due with what they had and all they had to tune duplexers was it's transmitter and receiver, a step attenuator, another 2way radio, Dummy loads and a good VOM. There is a procedure to do it like hat in an old ARRL Repeater Handbook Circa 1980.

Last January I tuned a old pair of WACO duplexers. with my NanoVNA. All fine since. Since you have no experience... CHECK the duplexers 1st before you start screwing around. READ up on everything on repeaters. Go to this site and download the white paper on "ANTENNA DUPLEXERS".. Print it and read it twice.



EMR is one of the oldest, most trusted in the business.. The Founder was a ham and knew his stuff..

A setup to check --NOTE CHECK--- a duplexer.. #1. carefully calibrate NanoVNA for 3-4 megs around the frequencies of interest. Rough pictorial but you should get the drift of how to connect.

------------------ ch0 NanoVNA ch1-------------------------
| |
------------------CAN-------CAN------CAN--------------- |
CAN CAN CAN | |
CAN CAN CAN | |
+-----------
|
|
50 OHM DUMMY LOAD ------------------CAN-------CAN------CAN---------------
CAN CAN CAN
CAN CAN CAN

Set your marker frequencies for repeater input and output frequencies set display to make 2-3 passes 101 points X3..... as the plot bottoms out, at -50- -60 dB, the curve will get ragged there. You want the marker to be in the middle of the ragged area. I have not tried it yet, but I did buy a $5-10 20dB 0-2Ghz broad band amplifier, to install in the CH0 line to see if I can "raise" the plot to more accurately adjust the notch. Think of CH0 as a transmitter and CH1 as a receiver.
I also used this setup to measure SWR at inputs.
Swapping CH0 with the dummy load, will test both sides of the duplexer...

I used VNA saver as you can increase the number of points on a plot to X8.. all thought the sweep is slower. You can save your plots to a file or print them out. more practical than the NanoVNA alone.

Larry W8LM

OK, I got my analyzer few months ago and it is abut time for me to start using it.
My fist victim is going to be my Beverage " (sitting) on the fence setup".

I am NOT looking for accurate measurements , with precision of 5 decimal points , just get some idea how the wire behaves.

So - for starters - it is fed with very short length ( ~ 3 meters ) 450 Ohms "window line " .
How critical is it to "convert " such balanced feed to analyzer coax input?

Since the feed line is so short and ONE end of Beverage is GROUNDED - does it make much difference in measurements?
Cheers

73 Vaclav AA7EJ

John. Great idea.
I will try with my smart phone.
I am also going to try and do a screen p

In July 2020 I measured several chokes for an article in a magazine.

Compared two 240-31-cores. One with RG58, tight windings, and one with RG174, loose windings.
Of course, not one 31 core is equal to the other, but it gives a nice comparison. The core with RG58 is in use in my station for 3.5MHz - 10MHz. The RG174 (loosely wound) core was measured out of curiousity.

Draw your own conclusions.

Measurements were made with a nanoVNA H3.2 and nanoSAVER v0.1.2


To Hugen: thanks for bringing this nice device to market
To Rune Broberg: thank you for this marvellous piece of software.

73,

Arie PA3A


Op 11-2-2021 om 02:28 schreef Jim Lux: