Re: Anybody happens to know VF of this cable ?
Very good point about actual VF vs published VF. There are several ways to quickly get the actual VF of the cable using a NanoVNA but the OP ("Anne") doesn't like posts that go beyond specifically answering her question.
OK, humor me and tel me TWO of several ways to ":get the actual VF of the cable using a NanoVNA"
PS
According to last test - my " digital ( other superlatives intentionally removed ) RG6" VF is .66 !
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Re: Estimating coaxial cable length - using TDR
Roy J. Tellason, Sr
It looks as "this TDR" subject has life of its own,,,
The Agilent article will take me some time to digest...
At present I am trying to "run the source code of nanoVNASaver" in Qt debug mode.
Tentatively I will try to make "TDR" and "TDR display " to match...
My last test - finding known length of my "fancy digital RG6" of VF . 82 ( VF value thanks to the group replies, appreciate that )
matches my inch stick when I set the VF to .66 !
So... is it real or Memorex?
Is my fancy RG6 mislabeled and it is really plain RG6 of .66 VF?
Where is the problem ?
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Re: Anybody happens to know VF of this cable ?
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Ok, you said "there are several ways to determine the actual VF of a cable using a NanoVNA". WHY did you stop there? Dispense with the attitude and just TELL US what these methods are!!------ Original message------From: Roger Need via groups.ioDate: Sun, Jun 11, 2023 3:05 PMTo: [email protected];Cc: Subject:Re: [nanovna-users] Anybody happens to know VF of this cable ?On Sun, Jun 11, 2023 at 11:59 AM, Joe WB9SBD wrote:
Now something to remember,
The VF can be FAR from that spec.
I have seen Brand New cables that were different THAN THE SPECIFIED VALUE.
And as cables age, and it seems this stuff is OLD, that it changes
sometimes a LOT as it gets older!
Joe, Very good point about actual VF vs published VF. There are several ways to quickly get the actual VF of the cable using a NanoVNA but the OP ("Anne") doesn't like posts that go beyond specifically answering her question. Roger
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Re: Estimating coaxial cable length - using TDR
On Saturday 10 June 2023 02:04:13 pm Roger Need via groups.io wrote: For more details on how the S11/IFFT method of TDR works this tutorial by Agilent is quite informative. ?It includes details on why "windowing" the data is necessary, how to determine the upper stop frequency required based on estimated cable length, why the lower start frequency should be close to DC and other considerations.
Some intersting reading, there. -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin
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Re: When I connect NanoVNA Saa-2N to the USB-port
Sorry, it was the USB-cable. Should have used the one included.
-Oddleiv
s?n. 11. juni 2023 kl. 14:33 skrev Oddleiv Tungland <oddleiv@...>:
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s?n. 11. juni 2023 kl. 14:27 skrev Oddleiv Tungland <oddleiv@...>:
the display starts to flicker.
-Oddleiv
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Ok now, is there a easy way to figure out the resonance of the antenna?
I'm useing a different whip and ground plane so the factory (height) on the coil is going to be off so I'm wondering if there is a easy way to get a idea of where the coil is setting the antenna up at.
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NanoVNA-H not seen by windows11 (no com port)
#nanovna-h
Hello all,
I have a NanoVNA-H wich used to work under W10 with Nanosaver app. After upgrade to W11, when I connect the NanoVNA to usb port nothing happens, no new com port is seen under device manager.
Wonder if anyone had the same problem. Any help its welcome.
thank you.
Marius
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Sorry, didn't read your post correctly. Make sure you save the calibration, Then look on the left of the display to make sure you recall the saved calibration.
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On 2023-06-11 11:16, Mike Anderson/KF?AWL via groups.io wrote: Ok new question.
I'm following the setup in the beginner's guide for process of calibration, get it done according to the guide and try to verify with the Smith chart . I screw my open to port 1 trace 1 (trace 0 is my swr trace) were I did the calibrate and according to the guide it should go to the far right of the Smith chart. It dont, it just sits in the same place. What am I doing wrong here?
I'm following it step by step!
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Far right is very high resistance, far left is very low resistance. Your open calibration looks good!
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On 2023-06-11 11:16, Mike Anderson/KF?AWL via groups.io wrote: Ok new question.
I'm following the setup in the beginner's guide for process of calibration, get it done according to the guide and try to verify with the Smith chart . I screw my open to port 1 trace 1 (trace 0 is my swr trace) were I did the calibrate and according to the guide it should go to the far right of the Smith chart. It dont, it just sits in the same place. What am I doing wrong here?
I'm following it step by step!
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Re: Anybody happens to know VF of this cable ?
On Sun, Jun 11, 2023 at 11:59 AM, Joe WB9SBD wrote:
Now something to remember,
The VF can be FAR from that spec.
I have seen Brand New cables that were different THAN THE SPECIFIED VALUE.
And as cables age, and it seems this stuff is OLD, that it changes
sometimes a LOT as it gets older!
Joe, Very good point about actual VF vs published VF. There are several ways to quickly get the actual VF of the cable using a NanoVNA but the OP ("Anne") doesn't like posts that go beyond specifically answering her question. Roger
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Re: Anybody happens to know VF of this cable ?
Now something to remember,
The VF can be FAR from that spec.
I have seen Brand New cables that were different THAN THE SPECIFIED VALUE.
And as cables age, and it seems this stuff is OLD, that it changes sometimes a LOT as it gets older!
Joe WB9SBD
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Show quoted text
On 6/11/2023 1:07 PM, Jim Shorney wrote: Yes, well, the point was to have the OP go the last mile to get the information by following the archive link and maybe learn a thing or two in the process. This probably comes from having a mother who was a teacher. She had some clever ways of tricking me into learning things...
73
-Jim
NU0C
On Sat, 10 Jun 2023 20:31:21 -0700
"Jim Lux"<jimlux@...> wrote:
foam, 82% VF
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Re: Anybody happens to know VF of this cable ?
Yes, well, the point was to have the OP go the last mile to get the information by following the archive link and maybe learn a thing or two in the process. This probably comes from having a mother who was a teacher. She had some clever ways of tricking me into learning things... 73 -Jim NU0C On Sat, 10 Jun 2023 20:31:21 -0700 "Jim Lux" <jimlux@...> wrote: foam, 82% VF
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Ok got the Smith chart working in conjunction with SWR reading on port one and verified my calibration (honestly it was a fluke and not sure how I did it lol)
So got that issue solved this new software in this one has more settings and things in the menu that weren't there before and are not meantioned in the beginner's guide now.
So on we go!
Thanks for the help guys ill be confused again I'm sure lol
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Use the Smith Chart display and make sure that the trace is set to S11
And you (very confusingly) need to connect to and calibrate port 0 for S11 measurements. Port 1 (normally 2) is the return port for S21 measurements.
I think that the original nanoVNA designer did a disservice when they labeled the RF ports 0 and 1 (computer style) when everyone else in the known universe's VNA (and the S-parameter numbering and equations) use ports 1 and 2; S11, S21 is a lot more meaningful that way.
Similarly, everyone else uses trace 1,2,3... and save/recall register 1,2,3...
This kind of avoidable confusion has got to be tough on beginners.
Best regards, Don Brant
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Re: When I connect NanoVNA Saa-2N to the USB-port
Although we occasionally talk about other products with the NanoVNA name, this group is primarily about the original NanoVNA design by edy555 and the improvements of it by Hugen (NanoVNA-H and NanoVNA-H4). You might get better information about your problem with the SAA2 on the group for that product ( /g/NanoVNAV2 - from the original name of that design) or on its web site ( ).
On Sun, Jun 11, 2023 at 9:43?AM Rick Murphy <k1mu.nospam@...> wrote: The USB-C port on the NanoVNA systems is reported to be rudimentary, and
not capable of properly negotiating the voltage it wants. 5 Volts is
expected.
Use a USB-A to USB-C cable and this won't usually be an issue. Some cases
where the computer fed far too much voltage than the Nano could accept have
apparently fried the Nano, so be careful.
73,
-Rick
On Sun, Jun 11, 2023 at 8:46?AM Oddleiv Tungland - LA3GW <
Oddleiv@...>
wrote:
s?n. 11. juni 2023 kl. 14:27 skrev Oddleiv Tungland <oddleiv@...>:
the display starts to flicker.
-Oddleiv
--
Rick Murphy, D. Sc., CISSP-ISSAP, K1MU/4, Annandale VA USA
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On Sun, Jun 11, 2023 at 09:16 AM, Mike Anderson/KF?AWL wrote:
Ok new question.
I'm following the setup in the beginner's guide for process of calibration,
get it done according to the guide and try to verify with the Smith chart . I
screw my open to port 1 trace 1 (trace 0 is my swr trace) were I did the
calibrate and according to the guide it should go to the far right of the
Smith chart. It dont, it just sits in the same place. What am I doing wrong
here?
I'm following it step by step!
Use the Smith Chart display and make sure that the trace is set to S11 Roger
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Re: When I connect NanoVNA Saa-2N to the USB-port
Not familiar with setup, but the nano is "embedded " is some other hardware.
Can you actually see / observe the nano LED 's?
I believe one is a power / battery indicator and the other monitors the software.
My guess is - the battery is not fully charged and the LCD state is pretty much unknown...
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Ok new question.
I'm following the setup in the beginner's guide for process of calibration, get it done according to the guide and try to verify with the Smith chart . I screw my open to port 1 trace 1 (trace 0 is my swr trace) were I did the calibrate and according to the guide it should go to the far right of the Smith chart. It dont, it just sits in the same place. What am I doing wrong here?
I'm following it step by step!
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Re: Estimating coaxial cable length - using TDR
On Sat, Jun 10, 2023 at 11:44 AM, Jim Lux wrote:
Jim Lux,
I got a break from TDR by seeing "Swan Lake" , enjoyed the music , not sure about the ballet. My XYL comment was "woman body legs are not attached to the body..." BTW the antenna "mast" fell in recent windstorm, dummy forgot to add hose clamp to the first cammo pol;e and it broke . No damage to anything, just pride. I found a short piece of same, labelled RG6 cable so I can compare it with the unlabeled one. I need to go back to grammar school and study Fourier to make sense of all of this. I still believe the nanoVNASaver has an issue with using the "sweep" entries... Also the "TDR" and the TDR display options do not match - the "POP up sub menu in particular. PS During my college study there was a joke going around with one of the professors pet question "draw me a graph..."... if you forgot to add dimensions to either axis you have failed the exam. TDR graph is missing the "y axis" dimension. 73 Vaclav AA7EJ of this.
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Re: Anybody happens to know VF of this cable ?
Thanks, all reposes are greatly appreciated.
73 Vaclav AA7EJ
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Mike Anderson/KF?AWL
Roger Need
Jim Shorney
Donald S Brant Jr
Shirley Dulcey KE1L