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Yeah, there is flux all over and it looks like someone learning to solder assembled it. \_('_')_/

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On Fri, 13 Dec 2019 at 9:51 am, Oristo<ormpoa@...> wrote: Hi Larry -

I picked up a bridge from the eBay link above.
The build quality is poor and the 2, 100 ohm resistor pairs are each not in parallel.
So even though the board is green,
it's no better than one of those blue boards with the same issues.

Sorry to learn that;? I suppose only ones from Ukraine are better.

At least it's fixable.

Leaving 100 Ohm resistors NOT connected in parallel improves sensitivity for differences at higher impedances,
but fixing coax terminations thru ferrite beads is necessary.

I am not sure that makes it an effective balun. Or maybe at best a voltage balun, but not a current balun - which is what antennas require. As I recall, it is not possible to make a current balun, other than 1:1 ratio on a single core.

Dale W4OP

Hi Larry -

I picked up a bridge from the eBay link above.
The build quality is poor and the 2, 100 ohm resistor pairs are each not in parallel.
So even though the board is green,
it's no better than one of those blue boards with the same issues.

Sorry to learn that; I suppose only ones from Ukraine are better.

At least it's fixable.

Leaving 100 Ohm resistors NOT connected in parallel improves sensitivity for differences at higher impedances,
but fixing coax terminations thru ferrite beads is necessary.

Hi Lajos
I see you open phase is -0.22 degree at 250MHz and that equals 2.44ps delay. That look like you are suing the male open adaptor which in my calibration document gives has a offset one way delay of 1.62ps.
The 0.98ps is the one wat Offset delay when the SMA female adaptor is left unterminated during the calibration which after my calculation gives 1.111ps and that is so to speak the same as thee 0.1degree as the accuracy of the angle readout is limited by rounding to 1 or 2 decimal digits. There will always be fluctuations form sweep to sweep du to noise.
0.98ps is measured with the VNWA after calibration with my HP83033C 3.5 mm calibration kit.
I do not understand you comment "Now, next calculations you use 0,98 and 250, not 245,025. " where and when did I use these figures ?
Regarding the VNWA arbitrary values for calibration kits they can be converted to value to enter in the NanoVNA-saver calibration kit settings and that is a bit complicated for explaining in a mail response. I will make a document when I get time and publish of interest for those having VNWA software and want to use/purchase the SDR-Kits SMA and BNC and soon also N calibration standards with the NanoVNA .
The other way round the NanoVNA calibration kit is very easy to convert to VNWA as you just copy a calibration kit file to another name and use the simple settings and enter the two way delay data for short and open and the load data with two way delay data as indicated in my calibration document
Regarding the fringe C for load there is no easy way to find it an there might also be a delay and inductance to determine and requires a known calibration kit for determining these data.
One of my 3 NanoVNA loads are also broken
Kind regards
Kurt

-----Oprindelig meddelelse-----
Fra: [email protected] <[email protected]> P? vegne af pgc1682@...
Sendt: 13. december 2019 10:36
Til: [email protected]
Emne: Re: [nanovna-users] New version of NanoVNA-Saver: 0.2.1

Hi Kurt,

I tried your latest How_to_display_delay_shift_for_a_cable_in_NanoVNA_saver.pdf method.

Now I have many problems. I not understand what I do wrong, or what corrections/calibrations will be required.

See the attacment images. I think my nanovna calibrations not ok. Supplied coaxial cable not symmetrically spiraling inwards to centre smith diagram. Your calibration much better. I try this with different cable, also not good. Teflon dielectic cable, i think better than supplied. I currently not have semi rigid cable to better test. I will get it, but requires lots of time.

I use your method, and your calibration contans.

Now I use latest QRP 4.4 firmware, clearconfig executed, and instrument calibrated with your method.

Formerly, I have good calibrations without trick. It works well, I use many times, working good. But I lost it, I can't reproduce it. I not know why not.

Where from your 0.98 ps? I see on your document marker 1 cursor on 245,025Mhz S11 phase -0,1° so i get 1,134 ps, not 0,98ps. Now, next calculations you use 0,98 and 250, not 245,025.

Fringe C capatince not know how to compute what it causes (more than about clockvise phase shift), and i not know how to measure or compensate manually. Maybe my Hugen-H like calibrators not same? I measured load, only with multimeter. I get 49,9 ohm final value, (subtracted the internal 0,4 ohm error). Not a precise instrumnet, and not 4 leg method, but i think load resistance value good.

I see DG8SAQ WVNA arbitrary calibration formulas to oslt. I not understand this, which value where from. C0 - C3 L0 - L3 Resistance Delays and if exist loss. Many high quality oslt has loss values. I think for amateur instrument more interesting the calibrator loss. I see many cheap connector have much higher loss than precision air dielectric oslt.

So, i cannot convert nanovna values to DG8SAQ WVNA and reverse. Another problem, on wvna original male oslt damaged by other user. Only female oslt in good conditions.

I alsa have some problem on Hugen like load. I see many time contact error. I heard from another nanovna user, his load also problematic. Short, and opens always good. I have there another sma load from used mobile phone system. No data, but i think all of them is good. Contact error never exist. I tried to use these loads for calibrations but i see only minor difference to Hugen like load.

I not know the best method to convert C1-C4 to simple C value.

73,
Lajos

Its both
1:9 transformer with the 9 side not connected to ground

--
NanoVNA Wiki: /g/nanovna-users/wiki/home
NanoVNA Files: /g/nanovna-users/files
Erik, PD0EK

Can "sweep" "center" "span" be entered on the same console command line?

No, at least in ttrftech firmware, only the first argument can be one of {start|stop|center|span|cw}

<sweep center 30000000> and;
<sweep span 1000000> work for me. But not;
<sweep center 30000000 span 1000000>

It is sad (to me) that so much code is wasted on useless "flexibility".

Is it really a balun or a 9:1 transformer? Only a CMRR measurement would show that up.

I find that today the word balun and unun are almost always used to describe a transformer with unknown CMRR spec.

Dale W4OP

#83 : On the Doubtfulness

Hello,

Allow us, please, to announce that, as it seems, we may just found the deep
source of doubtfulness and in the following way : we thought that we had to
think historically, that is with terms of the time all this measurement adventure
begun, that is with the available accuracy of the calculations -rather than
computations- of that time.

Therefore, also allow us, please, to announce that having already in hand the
last, fully proved, "new" formulation of this "one-port" method of computation
of S-parameters of (reciprocal) two-ports, we focus our next research steps in
this very direction : on the comparison of these "one-port" computation results
with the "classic" one of "two-port" measurement ones.

Sincerely,

gin&pez@arg

:83#

Hugen,
Is there going to be a selectable USB/serial port PC I/O mode for this version with the new uP?
ThanksLarry



On Fri, 13 Dec 2019 at 3:18 AM, hugen@...<hugen@...> wrote: I've made a new PCB for testing, it's working well now, but At the moment ADC1 can't read VBAT data correctly, and I can't get into DFU mode through the menu yet, I haven't found the cause of the problem yet, maybe to fix it after Christmas. Most of the circuits are the same as the current NanoVNA-H, so I don't think this is the next generation of NanoVNA, it's just the NanoVNA that replaced the MCU and has a larger screen, but that's probably the version that many people in this group need. If there are suggestions for changes that can be directly replied to this message, I will improve it.

The attachment is a screenshot.

hugen

Yesterday I received the Nooelec "Balun One Nine V2" and did limited testing. It uses a Coilcraft WB9-1 transformer, with a published 3dB bandwidth of .125-125MHz; interpolating the datasheet graph shows about .5-70MHz at the 1dB points.
I put it on the nano and set span 1-30MHz and calibrated OSL with 450 Ohms as the load.
Then attached 900 ohms and got SWR 2.0; attached 4500 ohms and got SWR 10.0.
I have not yet tested it with reactive loads.
Certainly not a lab-grade test accessory, but may be useful for characterizing parallel transmission lines and high-impedance HF antennas.
--KV5R

From: nanovnauser@...

my post code is ln95je,i put that and it says wrong format every time,tried it in caps too,same result,what should i put then?
==========================================

My account shows the address as "EH10 6**" with "**" replaced by the real postcode.

BTW: I bought a nanoVNA-F which is already cased and with a considerably larger screen. It does make a difference particularly reading the numbers!

Cheers,
David
--
SatSignal Software - Quality software for you
Web:
Email: david-taylor@...
Twitter: @gm8arv

Hi Kurt,

I tried your latest How_to_display_delay_shift_for_a_cable_in_NanoVNA_saver.pdf method.

Now I have many problems. I not understand what I do wrong, or what corrections/calibrations will be required.

See the attacment images. I think my nanovna calibrations not ok. Supplied coaxial cable not symmetrically spiraling inwards to centre smith diagram. Your calibration much better. I try this with different cable, also not good. Teflon dielectic cable, i think better than supplied. I currently not have semi rigid cable to better test. I will get it, but requires lots of time.

I use your method, and your calibration contans.

Now I use latest QRP 4.4 firmware, clearconfig executed, and instrument calibrated with your method.

Formerly, I have good calibrations without trick. It works well, I use many times, working good. But I lost it, I can't reproduce it. I not know why not.

Where from your 0.98 ps? I see on your document marker 1 cursor on 245,025Mhz S11 phase -0,1° so i get 1,134 ps, not 0,98ps. Now, next calculations you use 0,98 and 250, not 245,025.

Fringe C capatince not know how to compute what it causes (more than about clockvise phase shift), and i not know how to measure or compensate manually. Maybe my Hugen-H like calibrators not same? I measured load, only with multimeter. I get 49,9 ohm final value, (subtracted the internal 0,4 ohm error). Not a precise instrumnet, and not 4 leg method, but i think load resistance value good.

I see DG8SAQ WVNA arbitrary calibration formulas to oslt. I not understand this, which value where from. C0 - C3 L0 - L3 Resistance Delays and if exist loss. Many high quality oslt has loss values. I think for amateur instrument more interesting the calibrator loss. I see many cheap connector have much higher loss than precision air dielectric oslt.

So, i cannot convert nanovna values to DG8SAQ WVNA and reverse. Another problem, on wvna original male oslt damaged by other user. Only female oslt in good conditions.

I alsa have some problem on Hugen like load. I see many time contact error. I heard from another nanovna user, his load also problematic. Short, and opens always good. I have there another sma load from used mobile phone system. No data, but i think all of them is good. Contact error never exist. I tried to use these loads for calibrations but i see only minor difference to Hugen like load.

I not know the best method to convert C1-C4 to simple C value.

73,
Lajos

hugen,
The larger display size is great and if the > 50 dB dynamic range to 1500 MHz holds up in the final release then I'd say you have a winner. Does the larger flash_size allow you to increase the measurement points to at least 201? Will firmware developed for the NanoVNA-H be compatible with the F303 based product? Any idea what the target price will be?

- Herb

On Thu, Dec 12, 2019 at 10:28 PM, <nanovnauser@...> wrote:

my post code is ln95je,i put that and it says wrong format every time,tried it in caps too,same result,what should i put then?
======================================================================
Sorry, I assumed you were in the states so my extended zip code comment didn't really apply. I see ln95je is in Horncastle, England. If you haven't already done so you might try using LN9 5JE with a space for the postal code.

- Herb

I've made a new PCB for testing, it's working well now, but At the moment ADC1 can't read VBAT data correctly, and I can't get into DFU mode through the menu yet, I haven't found the cause of the problem yet, maybe to fix it after Christmas. Most of the circuits are the same as the current NanoVNA-H, so I don't think this is the next generation of NanoVNA, it's just the NanoVNA that replaced the MCU and has a larger screen, but that's probably the version that many people in this group need. If there are suggestions for changes that can be directly replied to this message, I will improve it.

The attachment is a screenshot.

hugen

my post code is ln95je,i put that and it says wrong format every time,tried it in caps too,same result,what should i put then?

I have purchased it from them without any hassle, and with complete
tracking online.

On Sat, Nov 16, 2019 at 12:59 PM, Oristo wrote>

A green (not blue) ~US$10 reflection bridge
e.g. from eBay
with matched SMA references (want a matched pair to calibrate nanoVNA CH1)

Oristo,
I picked up a bridge from the eBay link above. The build quality is poor and the 2, 100 ohm resistor pairs are each not in parallel. So even though the board is green, it's no better than one of those blue boards with the same issues.

At least it's fixable.
I've attached a couple of photos.

Hi Herb,
I think Erik or QRP (and maybe Rune) will have to answer that more accurately than me, as what I wrote was my interpretation of their explanation in a forum post waaaay back in October some time.?
... Larry

On Wed, Dec 11, 2019 at 12:46 PM, "[email protected] Notification" <[email protected]> wrote:

* /NanoVNA_Console_Commands_Dec 9-19.pdf ( /g/nanovna-users/files/NanoVNA_Console_Commands_Dec 9-19.pdf )

*Uploaded By:* Larry Rothman <nlroth@...>

*Description:*

This is the latest update of the Console Commands for the NanoVNA as of Dec 9th. It replaces the previous version. updated some command descriptions (per QRP's new v0.4.3 F/W) Please let me know of any errors or omissions.
=========================================================================

I have a question regarding the "sweep" command:

sweep - usage: sweep {start(Hz)} [stop] [points]
if no inputs: then prints current setup eg:300000000 500000000 101
otherwise, can force new sweep settings using the following commands:
start
stop
center
span
cw
set – sets sweep points

Can "sweep" "center" "span" be entered on the same console command line?

<sweep center 30000000> and;
<sweep span 1000000> work for me. But not;
<sweep center 30000000 span 1000000>

TKs

- Herb