¿ªÔÆÌåÓý

ctrl + shift + ? for shortcuts
© 2025 Groups.io
Date

Re: Where to Buy?

 

On Sun, Mar 29, 2020 at 08:39 AM, jac hil wrote:


The problem with P O Box is the battery in the VNA.
PO rules prohibit a lot of things that burn and record how the parcel was
shook in transit.
That is absolutely not true. The only restriction for Lithium batteries (or any other hazardous materials) is air freight. Nothing to do with a PO Box being the final recipient. The problem is not at the destination, but rather in the process to get it there. I have received many times various Lithium batteries for radios, cell phones etc, even the backup cell I needed to refit in my HP3468A DMM via my PO Box absolutely without any issues. Some of the bigger packages even had the Lithium battery inside sticker warning as required.

The ONLY valid reason to exclude a PO Box is if the shipment is being sent by UPS, Fedex, or DHL, which require a signature upon delivery, so they do not deliver to a PO Box address.

There are US based sellers on ebay (a lot of them chinese) that advertise shipping with USPS in capital big letters and still exclude PO Box on various smallish items, nothing hazardous. The reason is usually that they are drop shipping, and are not really the entity that will handle the shipping so they have no control over it, and are not even able to provide you with a tracking number, or just send you a fake one. Sometimes you end up with an Amazon box even tough you made your purchase on ebay. Been there seen it happen, now I steer clear of any seller that is US based that excludes PO Box. Something funny going on there for sure. Life is short why waste time with drop-shippers.

And as I said before, the PO Box address is my ONLY practical option for small packages. I am not in the US. I do have a street address as well, but only for freight cargo so it has a base charge and does not make sense for small items. Been doing mail forwarding for many years with 99.99% success rate.


Re: edy555 release 0.7.1-20200321 #firmware

 

Hi

I flashed this firmware into my NanoVNA-H4 and itworks ! .Anyhow it works normally under NanoVNASaver. ? In the menu I see several addon's but these are not (yet ?) supported by NanoVNASaver ofcourse.

The extra bandwith settings seem to work when standalone? , I see that the smaller the bandwith, the slower the display updates. The DFU option does not work on the H4.

Jos

Op 30-3DiSlord:-2020 om 08:44 schreef Compile version for NanoVNAt -H4 (0.7.1-20200321+ last improvement

a new item


Idon`t have hardware H4 for tests, but must work

At whis version added all my additional Bandwidth improvements, speed optimizations + bigger font from my old fixes to AA version


Re: Review of S-A-A-2 #nanovna-v2

 

you mention the schematic - can it be seen somewhere online?
=============================================
Marko,
The attached file is the version 2_2 schematic provided by Gabriel.

- Herb


Re: Review of S-A-A-2 #nanovna-v2

 

Schematics at:
gEDA format.

On Mon, 30 Mar 2020 at 11:15, <mcebokli@...> wrote:

Hello Herb,

you mention the schematic - can it be seen somewhere online?
I will definitely buy this, but I can not do it currently from Tindie, not
shipping to Slovenia (in fact, there is a quite long list of "no ship"
countries there). Hopefully, this will change - don't want to pay double at
Ebay.
Also, currently the postal service here in Europe is out of whack because
of COVID, I am waiting for some other parcels for quite long now, if they
will arrive at all. I will wait a bit anyway, order later, if still alive.
So, in the mean time I would like to at least study the schematic :-)

Marko Cebokli




Re: Review of S-A-A-2 #nanovna-v2

 

Hello Herb,

you mention the schematic - can it be seen somewhere online?
I will definitely buy this, but I can not do it currently from Tindie, not shipping to Slovenia (in fact, there is a quite long list of "no ship" countries there). Hopefully, this will change - don't want to pay double at Ebay.
Also, currently the postal service here in Europe is out of whack because of COVID, I am waiting for some other parcels for quite long now, if they will arrive at all. I will wait a bit anyway, order later, if still alive.
So, in the mean time I would like to at least study the schematic :-)

Marko Cebokli


Re: edy555 release 0.7.1-20200321 #firmware

 

Compile version for NanoVNA-H4 (0.7.1-20200321 + last improvements)



Idon`t have hardware H4 for tests, but must work

At whis version added all my additional Bandwidth improvements, speed optimizations + bigger font from my old fixes to AA version


Re: SMITH CHART TUTORIAL

 

Nbridgema wrote:
Reading off the chart, we see the following values:...
Would you please explain where these values are seen?
The answer is, you cannot directly read frequency off of the Smith chart.
There should be little notes and arrows added as annotation to the chart,
telling where the 14.0mhz, 14.175mhz, and 14.35mhz points of the blue arc are at.

The blue arc goes clockwise from 14.0mhz in the upper left to 14.35mhz in the lower right.
If you zoom in and put on your best reading glasses, you may see a little green pixel in the blue arc
just below the horizontal line identified as "0.2", this point on the blue arc is 14.175mhz.

The first entry of the table after the chart says that the reflection coefficient at 14mhz
is (-0.12, j0.26). That's a complex number, having a real part of -0.12 and an imaginary part of j0.26.
This corresponds to the upper left end of the blue arc.
The real part of -0.12 is slightly to the left of the center vertical axis of the chart, a bit more than halfway to that first -0.2 vertical line.
The imaginary part of j0.26 is up from the center horizontal axis of the chart, a bit above the first horizontal marker at 0.2.


There's all of four sentences in this tutorial describing the central concept of what a Smith Chart is:
Radio operators are inherently familiar with the concept of standing-wave ratio, i.e., a measure of how well a load
is matched to a transmission line. A slightly more obscure concept is that of the reflection coefficient.
Notated using the Greek letter gamma (¦£), the reflection coefficient describes how much of an
electromagnetic wave is reflected by an impedance discontinuity such as a mismatched load. ...
First, let¡¯s plot the real and imaginary components of ¦£ for this DUT on a rectilinear graph.
So I'd say Aldo's tutorial is not very useful to someone starting out, you pretty much have to already know
what a Smith Chart is. The title should give a hint of this: "Revisiting the Smith Chart".
But if you do understand the basics, there is plenty of good information there.

Here's an old post about a different Smith Chart tutorial: /g/nanovna-users/message/5223
This tutorial does try to explain in simple terms what a Smith Chart is.
That entire thread might still be of interest to those thinking about how to better document these VNA's.

Another good resource for understanding the Smith Chart is at

Jerry, KE7ER


Re: SMITH CHART TUTORIAL

 

Thanks for trying to help, Tom in AZ, but what good will it do to study hundreds of hours to try to make sense of that one line?
That is, I do not see on the chart any markings that allow scaling frequency relative to the (nearly invisible) green mark.

I used Smith charts to guide fabrication of waveguide filters, more years ago than I care to remember! : > )

--
I_B_Nbridgema


Re: S-A-A-2 Programming Problem #nanovna-v2

 

On Sun, Mar 29, 2020 at 11:27 AM, CT2FZI wrote:

Do you think a specific groups.io group would help?
==============================================
³¢³Ü¨ª²õ,
So far only about 150 S-A-A-2 units appear to have been sold before the first production run ended. I don't know if that is enough volume to warrant another user group, but only time will tell. This groups.io forum and the NanoVNA Facebook page also support the S-A-A-2. If you can get the S-A-A-2 manufacturer to designate your forum as an official support site that would be advantageous.

- Herb


Re: SMITH CHART TUTORIAL

 

There several tutorials in the files section, I've spent may years in
electronics and I still need a refresher from time to time. Read the
tutorials and it will clarify
Tom Sides KI7FTK
skype: Thomas Sides
4243 e. st Charles ave
Phx AZ 85042



On Sun, Mar 29, 2020 at 11:38 AM Nbridgema via Groups.Io <nbridgema=
[email protected]> wrote:

Aldo, in your tutorial is said:

Reading off the chart, we see the following values:...
Would you please explain where these values are seen?

Thanks!!
--
I_B_Nbridgema




Re: SMITH CHART TUTORIAL

 

Aldo, in your tutorial is said:

Reading off the chart, we see the following values:...
Would you please explain where these values are seen?

Thanks!!
--
I_B_Nbridgema


Re: S-A-A-2 Programming Problem #nanovna-v2

 

Hi there,

Do you think a specific groups.io group would help?

I have created one already, as I am waiting for my unit, but I am not sure
if its impolite to mention it here.

*73 de ³¢³Ü¨ª²õ, CT2FZI*




<>

On Sun, 29 Mar 2020 at 17:42, hwalker <herbwalker2476@...> wrote:

On Sat, Mar 28, 2020 at 09:53 PM, Gabriel Tenma White wrote:
I can confirm that currently the only way to exit USB mode is to toggle
the power switch. I'll look into adding a register to allow changing modes.

The USB interface always outputs raw, uncalibrated values, as is in the
user manual. The reason is the assumption that the PC software always has
superior calibration routines (e.g. supporting arbitrary cal kit
parameters) and it is far less error prone if you can't be confused whether
you are readin calibrated or uncalibrate values.
=============================================================
Gabriel,
Thanks for your response. I understand blanking the display while
NanoVNA-QT or similar programs are running to increase the speed of data
transfers. Plenty of commercial applications do the same thing. For small
scripts, where you just want to work with the trace data currently on the
display, it would really help if you could add a firmware command to
un-blank the display, and also a firmware command to transfer corrected
CH0 and CH1 data.

Do you know it the client, HCXQS group, plans on a support forum for
the S-A-A-2?

Regards,

- Herb




Re: Where to Buy?

Eric KE6US
 

Or an amazon drop box if one is not far away. They are all over the place. The local Rite Aid, Ralphs,? UPS Store and health food store all have them within two miles of me.

Eric KE6US

On 3/29/2020 8:39 AM, jac hil wrote:
The problem with P O Box is the battery in the VNA.
PO rules prohibit a lot of things that burn and record how the parcel was
shook in transit.

Amazon follows the rules, but some of the flighty others don't. Or you get
a VNA with out a battery.

Could suggest a friend to drop ship to

Good luck


On Sun, Mar 29, 2020, 11:33 AM <nanovnagroup@...> wrote:

OK I am trying to order it but turns out they don't send to US PO Box
addresses which in this case is my only practical option. Why in the world
would you put such a stupid restriction on this small sized purchase???
Unless this is being drop-shipped which I would not be surprised at all
give amazon's sales system where you never know from where you are really
getting your item from. This is why I hate amazon, and will wait for it to
turn up on ebay at a similar price and zero complications.

SORRY AURSINC: NO SALE TODAY.




Re: S-A-A-2 Programming Problem #nanovna-v2

 

On Sat, Mar 28, 2020 at 09:53 PM, Gabriel Tenma White wrote:
I can confirm that currently the only way to exit USB mode is to toggle the power switch. I'll look into adding a register to allow changing modes.

The USB interface always outputs raw, uncalibrated values, as is in the user manual. The reason is the assumption that the PC software always has superior calibration routines (e.g. supporting arbitrary cal kit parameters) and it is far less error prone if you can't be confused whether you are readin calibrated or uncalibrate values.
=============================================================
Gabriel,
Thanks for your response. I understand blanking the display while NanoVNA-QT or similar programs are running to increase the speed of data transfers. Plenty of commercial applications do the same thing. For small scripts, where you just want to work with the trace data currently on the display, it would really help if you could add a firmware command to un-blank the display, and also a firmware command to transfer corrected CH0 and CH1 data.

Do you know it the client, HCXQS group, plans on a support forum for the S-A-A-2?

Regards,

- Herb


Re: Where to Buy?

 

The problem with P O Box is the battery in the VNA.
PO rules prohibit a lot of things that burn and record how the parcel was
shook in transit.

Amazon follows the rules, but some of the flighty others don't. Or you get
a VNA with out a battery.

Could suggest a friend to drop ship to

Good luck

On Sun, Mar 29, 2020, 11:33 AM <nanovnagroup@...> wrote:

OK I am trying to order it but turns out they don't send to US PO Box
addresses which in this case is my only practical option. Why in the world
would you put such a stupid restriction on this small sized purchase???
Unless this is being drop-shipped which I would not be surprised at all
give amazon's sales system where you never know from where you are really
getting your item from. This is why I hate amazon, and will wait for it to
turn up on ebay at a similar price and zero complications.

SORRY AURSINC: NO SALE TODAY.




Re: Where to Buy?

 

OK I am trying to order it but turns out they don't send to US PO Box addresses which in this case is my only practical option. Why in the world would you put such a stupid restriction on this small sized purchase??? Unless this is being drop-shipped which I would not be surprised at all give amazon's sales system where you never know from where you are really getting your item from. This is why I hate amazon, and will wait for it to turn up on ebay at a similar price and zero complications.

SORRY AURSINC: NO SALE TODAY.


Re: S-A-A-2 Programming Problem #nanovna-v2

 

Gabriel,

What program did the team use to simulate the PCB with the various components? I want to simulate (initially) some lumped component (SMD L and C) filters till 1GHz on a double sided FR4 PCB and looking for a free tool with an acceptable learning curve.
I found Ansoft Designer SV but that requires some study time. Can you recommend something?

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


Re: S-A-A-2 Programming Problem #nanovna-v2

 

That sure makes for some mystery, Gabriel! Why do you use a pseudonym?

Randy
NC8U

On Mar 28, 2020, at 9:53 PM, Gabriel Tenma White <OwOwOwOwO123@...> wrote:

btw the V2 team is not just me ;) I'm just the only one publicly talking about it and even then I don't use my real name ;)

I can confirm that currently the only way to exit USB mode is to toggle the power switch. I'll look into adding a register to allow changing modes.

The USB interface always outputs raw, uncalibrated values, as is in the user manual. The reason is the assumption that the PC software always has superior calibration routines (e.g. supporting arbitrary cal kit parameters) and it is far less error prone if you can't be confused whether you are reading calibrated or uncalibrate values.

The VNA logic in the firmware was written from scratch, and we haven't yet implemented calibration interpolation (it wasn't removed, just never implemented). Personally I've not had good experience with using interpolation on other VNAs that support it; I've found it to give wrong results every time unless you have an insanely high number of sweep points (1000). However if there is popular demand we can go and implement interpolation.



Re: Analysing Input Impedance Matching Circuit for the NE602

 

I have now made up my NE602 mixer circuit on prototype board and have tested it again using 1 to 8 turn transformers and (as suggested by Roger above) 1 to 7 transformers.

The nanovna-saver images show that when attached to the NE602 the 1:7 turns ratio is very slightly better at 7.15MHz:

1:8 VSWR 1.885
1:7 VSWR 1.818

1:8 return loss -10.26dB
1:7 return loss -10.75dB

Looking at the spectrum analyser plots though it looks like the 1 to 8 transformers are slightly better for output gain and reducing the level of the closest intermodulation peaks to my IF frequency of 10MHz:

1:8 output with -30dB input is -15.18dB
1:7 output with -30dB input is -15.63dB

I think for now I am going to keep the 1 to 8 turns ratio as it gives a slightly higher output and the two closest intermodulation peaks to 10MHz are a little lower with this turns ratio but the difference for 8 vs 7 turns appears to be very small with a 7.15MHz RF input and 10MHz IF output.


Re: Review of S-A-A-2 #nanovna-v2

 

On Sat, Mar 28, 2020 at 10:49 PM, Joe Burkleo wrote:

One thing I have not seen in the spec's so far is what the output level is.
Have you measured that or do you know what it is?
If I remember correctly the original version was in the -10 dbm range.
==========================================================
Joe,
I haven't gotten around to measuring the output levels. I'm not sure how accurate my power meter is pass 1 GHz. If it helps these are the levels that Gabriel has annotated on her schematic.

IN to OUT transmission: ?10dB
IN to REFL (OUT shorted): ?30dB
IN to REFL (OUT open): ?30dB
Coupling factor: ?20dB

I not sure if the -10dB IN to OUT transmission is really dBm or actual loss through the directional coupler. Most directional couplers I've used have less than a dB through loss.

- Herb