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Here is a link to the "official" SD cared formatter by the SD Association



Roger

Hi all,i have just installed firmware ver 1.2.15,trouble is the active trace is on logmag,i see no options to set the active trace to swr,am i missing something? .73 and TIA

On 25/11/2022 18:48, Michael Reid wrote:

Hello Larry...thanks for response...I may have found the answer in
"messages"...my card is 32Mb and many responses to this "fail to write" are
resolved with a slower 16GB card, so I ordered some...
in reply to your questions, 1. new card, never used, never put into my
computer; 2. inserted in Nano with power off; 3. never put into my
computer...
Mike

You could try formatting the card in a camera first,

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

Hello Larry...thanks for response...I may have found the answer in
"messages"...my card is 32Mb and many responses to this "fail to write" are
resolved with a slower 16GB card, so I ordered some...
in reply to your questions, 1. new card, never used, never put into my
computer; 2. inserted in Nano with power off; 3. never put into my
computer...
Mike

On Thu, Nov 24, 2022 at 3:30 PM Larry McElhiney via groups.io <lmcelhiney=
[email protected]> wrote:

Hi Michael,

1) Have you previously written to that card or is it the first time.
(I.e., compatibility)

2) Was the card in the slot when you powered up or did you insert it with
power on?
(Best to insert and remove with no power.)

3) When you read the card from your computer do you always reject the card
electronically before removing it?

Hope it gets resolved for you.

Larry
AC9OX

sorted,it was the vervier dial on cap 2,the shaft was making intermitent contacts to ground,was using a solid brass coupler not insulated,now sorted,cheers 73 de m3vuv Paul.

General advice, Ken G3YKI, identify who you are responding to correctly! Just for your information, I know this wasn't directed to me but there could be a great number of people called Paul who could be subscribed to this group and all will be scratching their heads at seeing your post hit their inbox!

General advice, and please do not be offended, Paul.
If you have a long story, divide it up into several shorter sentences. It will be easier to get your message across and you will find it helps you to consider the problem more clearly yourself.

If r93 is a 10 ohm resistor, try shorting r93.
/g/nanovna-users/topic/micro_sd_card_issue/94630098?p=,,,20,0,0,0::recentpostdate/sticky,,,20,2,20,94630098,previd%3D1668372635506758650,nextid%3D1666746808442404351&previd=1668372635506758650&nextid=1666746808442404351

Hi Michael,

1) Have you previously written to that card or is it the first time. (I.e., compatibility)

2) Was the card in the slot when you powered up or did you insert it with power on?
(Best to insert and remove with no power.)

3) When you read the card from your computer do you always reject the card electronically before removing it?

Hope it gets resolved for you.

Larry
AC9OX

Most likely need to use a different card. Some are not compatible.
Search the messages here for SD card to see what has been shared by others
on this topic.

New NanoVNA-H4 with latest DiSlord v.1.2.00 upgrade, Clk SD CARD, Clk Save S1P and enter a name, Clk Return gives message "Fail Write". any suggestions???
Thanks in advance, Mike

On Thu, Nov 24, 2022 at 07:25 PM, Jim Lux wrote:

That's not generally true

Jim,
Ok, my bad, my answer was too short, I should have written: Don't be surprised if you measure 50 Ω - and if you do not see 50 Ω think twice what could be the reason. You gave good examples of influence:

On Thu, Nov 24, 2022 at 07:25 PM, Jim Lux wrote:

only if the power is on
other ports are terminated
blocking capacitor
design frequency
...

On Thu, Nov 24, 2022 at 07:25 PM, Jim Lux wrote:

be careful measuring the ports of RF devices with a ohmmeter

You could measure the port resistance of the VNA with a VNA - oops, catch 22 :)

Martin

On 11/24/22 9:29 AM, Ho-Ro wrote:

On Thu, Nov 24, 2022 at 05:47 PM, Paul M3VUV wrote:

measured the resistance on the s11 port on my vna ... it read 49 ohms ... is that normal ... ?

On a NanoVNA the CHO port connects to a bridge with ~50 ohm DC resistance. See the schematic of at least one version.

CH1 connects to a attenuator, also with approximately 50 ohm DC resistance.

All RF devices have input and output resistance of 50 Ω - unless you're in the TV business (they have 75 Ω) - otherwise youi'll get reflections (bad SWR).

That's not generally true - A lot of devices will have a RF impedance of 50 ohm resistive, but that's also only if the power is on and if the other ports are terminated in their expected impedances. And at the design frequency.

For example, a Bias T might show infinite DC resistance, because there's a blocking capacitor.

a typical power divider will NOT show 50 ohms DC resistance, depending on the configuration. A Wilkinson, certainly not, since it depends on the impedance transformation of the 1/4 wavelength lines. Same with a Lange coupler.

A "triangle" resistive power divider might show 50 ohms DC, if the output ports are terminated in 50 ohms.

One does want to be careful measuring the ports of RF devices with a ohmmeter, too. For instance the NanoVNA2 has some RF switches connected directly to the ports, and depending on the voltage of your ohmmeter, those could be damaged.

On Thu, Nov 24, 2022 at 05:47 PM, Paul M3VUV wrote:

measured the resistance on the s11 port on my vna ... it read 49 ohms ... is that normal ... ?

All RF devices have input and output resistance of 50 Ω - unless you're in the TV business (they have 75 Ω) - otherwise youi'll get reflections (bad SWR).

Martin

On Thu, Nov 24, 2022 at 04:45 PM, Paul M3VUV wrote:

Hi ,i have loaded this but cant seem to get swr to show on trace 1,it says
logmag,it used to have swr in yellow numerals in the top middle of the screen
with my old fw,any ideas?.

Paul,

Trace 1? Yellow is the color of the 1st trace (Trace 0) - but nevertheless:

Menu - Display - Trace - set Trace 0 active - Back - Format S11 (Refl) - set SWR active

Enable/disable the other traces accordingly.

Martin

Hi all,long story my homebrew pi network atu wasnt tuning so stuck my v2 vna on it to have a look,at one point in the c2(variable cap nearest the output jack for the rig)looked as iff the vanes were shorting to ground,after removing the said cap it actualy looked ok but both sides looked like shorting to ground,the cap was still wired to the atu at this point, also the vna was conected to the atu,my meter was belling out between both legs of the cap and ground,i disconnected the vna and it stopped buzzing,i then measured the resistance on the s11 port on my vna,ie the center pin and outer of the s11 plug,it read 49 ohms low enough to make my fluke 87 dmm buzz on resistance mode,is that normal or a diode sc in my vna front end?.

Hi ,i have loaded this but cant seem to get swr to show on trace 1,it says logmag,it used to have swr in yellow numerals in the top middle of the screen with my old fw,any ideas?.

On 11/24/22 5:57 AM, N3MEL - Glenn wrote:

Is there a document that better explains what the returned data from a sweep really means?

In terms of the raw message from the NanoVNA (in response to the "data" command)?

It's real and imaginary of the reflection coefficient(for CH0) or transmission coefficient (for CH1)

You'll also need to do a "sweep" command which returns the start and stop frequency, and number of points.


The document I use is a pdf from 2019 called NanoVNA_Console_Commands_Dec 9-19.pdf

It's on the wiki here
/g/nanovna-users/wiki#For-Beginners-and-Experienced-Users

73 de Glenn N3MEL
(FRNPA) 1st Responders Network of Pa
PKT:145.090 &?VARA HF:3.596?WL2K:145.670
Emergency Coordinator
Chester County ARES/RACES

Is there a document that better explains what the returned data from a sweep really means?

73 de Glenn N3MEL
(FRNPA) 1st Responders Network of Pa
PKT:145.090 &?VARA HF:3.596?WL2K:145.670
Emergency Coordinator
Chester County ARES/RACES

I would also encourage you to try PayPal, and to include any independent statements you can get about the non-delivery of your item.

I raised a case with eBay about non-delivery of an item from a UK seller which may, in fact, have never been sent. eBay were unhelpful and did the same thing to me as they did to you: removed the item from my "purchased" list as soon as the case was opened. Fortunately I had email copies of all the invoices, shipping advice, etc. I submitted these to PayPal, and received a commitment to resolve the case one way or the other within a couple of weeks. Within an hour or two of submitting the case to PayPal, eBay closed the case - despite their tardiness in getting an actual human to discuss my case (never did achieve that). A few days later PayPal refunded my money, including shipping, taxes and foreign exchange charges. Although the amount involved was not huge, I considered the PayPal purchasing charges to be well worthwhile.

Don't waste your time with eBay, but do see if you can get some independent statement about the fictitious package for PayPal. And, as others have said, stay with the more reputable sellers - I only buy from "RF" oriented sellers (check out their "other items") with manufacturers' recommendations.

Regards, Peter.