Re: negative impedance values in smith chart
Check you calibration
Op 19-2-2020 om 12:12 schreef Hern¨¢n Freschi:
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I recently tried to measure input impedance on a helical filter. the problem is, the plot went outside the smith chart, and the marker showed negative impedance values and other crazy stuff.
what could be the cause for this?
the filter was only 137mhz so it should be well within the range of the VNA. the expected impedance is 50 ohms. the filter passband was measured correctly, and the return loss showed a sane value. only the smith chart was empty.
thanks.
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negative impedance values in smith chart
I recently tried to measure input impedance on a helical filter. the problem is, the plot went outside the smith chart, and the marker showed negative impedance values and other crazy stuff.
what could be the cause for this?
the filter was only 137mhz so it should be well within the range of the VNA. the expected impedance is 50 ohms. the filter passband was measured correctly, and the return loss showed a sane value. only the smith chart was empty.
thanks.
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Re: Anyone had news from Maggie King?
Hi
I just had a shipment from them.
It's due for delivery tomorrow.
She has didn't respond to any messages, but the package got shipped.
Kind Regards
ZS1SCI
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Re: Android app cable not working!
Before I go to that testing, my Windows 10 PC communicates fine with
the Nano using nanovnasaver...
but two android phones, three cables and using teh web app as well as
the android app, always the same "no device found" error.
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On Tue, Feb 18, 2020 at 6:49 PM Larry Rothman <nlroth@...> wrote:
Dumb question: have you tried using TeraTerm on a PC to talk to your Nano via the console?
If that works, then refer to the following thread and see if your phone can talk through a terminal app...
/g/nanovna-users/message/9978
On Tue, 18 Feb 2020 at 6:15 PM, Kayak<kayak1176@...> wrote: weird. I just received my THIRD OTG adapter cable and two USB-A to
micro-USB cables, and tried the supposedly always-compatible nano web
version on the J7 Prime and the LG Aristo, no joy whatsoever. 'no
compatible device found' doesnt work in the app either.
Two apps
Three OTG adapter caboles
Two phones
Two USB cables
Zero luck.
On Tue, Feb 18, 2020 at 1:48 PM gary <w9td@...> wrote:
Here is my Willkac cable working with a Moto X to the nanoVNA. The X is running Android 7 and asks if the nanoVNA should be allowed to use the USB when it is connected. The NanoVNA app just works without fuss. Note that the Wiilkac cable is a standard type A USB 3 socket not type C.
Gary W9TD
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Re: Anyone had news from Maggie King?
I went to my alibaba before asking question here.
thanks Hugen for the answer, I paid the extra 10$ for DHL shipping cause I
wanted it faster.. I do understand there was a longueur holiday then
expected. so will have to wait.
Left a message yesterday. still no response.. I just hope she is ok , same
for Hugen.
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Le mar. 18 f¨¦vr. 2020 ¨¤ 16:56, PA7RG <robert.pa7rg@...> a ¨¦crit : In my alibaba I found this.
Feb. 15, 2020, 03:17:44 PST., the order has been shipped.
So I¡¯ll have to wait.
Best regards,
Robert PA7RG
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Re: Android app cable not working!
Dumb question: have you tried using TeraTerm on a PC to talk to your Nano via the console? If that works, then refer to the following thread and see if your phone can talk through a terminal app... /g/nanovna-users/message/9978 On Tue, 18 Feb 2020 at 6:15 PM, Kayak<kayak1176@...> wrote: weird. I just received my THIRD OTG adapter cable and two USB-A to micro-USB cables, and tried the supposedly always-compatible nano web version on the J7 Prime and the LG Aristo, no joy whatsoever. 'no compatible device found'? doesnt work in the app either. Two apps Three OTG adapter caboles Two phones Two USB cables Zero luck.
On Tue, Feb 18, 2020 at 1:48 PM gary <w9td@...> wrote:
Here is my Willkac cable working with a Moto X? to the nanoVNA. The X is running Android 7 and asks if the nanoVNA should be allowed to use the USB when it is connected. The NanoVNA app just works without fuss. Note that the Wiilkac cable is a standard type A USB 3 socket not type C.
Gary W9TD
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Re: Android app cable not working!
weird. I just received my THIRD OTG adapter cable and two USB-A to
micro-USB cables, and tried the supposedly always-compatible nano web
version on the J7 Prime and the LG Aristo, no joy whatsoever. 'no
compatible device found' doesnt work in the app either.
Two apps
Three OTG adapter caboles
Two phones
Two USB cables
Zero luck.
toggle quoted message
Show quoted text
On Tue, Feb 18, 2020 at 1:48 PM gary <w9td@...> wrote:
Here is my Willkac cable working with a Moto X to the nanoVNA. The X is running Android 7 and asks if the nanoVNA should be allowed to use the USB when it is connected. The NanoVNA app just works without fuss. Note that the Wiilkac cable is a standard type A USB 3 socket not type C.
Gary W9TD
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Re: Functions of the rocker switch
Some of the forum members including myself have removed the jog switch and installed buttons.? Check the files section for hardware mods.? On Tue, 18 Feb 2020 at 5:34 PM, DaveH52<ac2gl.dave@...> wrote: I think it's primary function is to break. Looks like I've got some inventing to do.
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Re: Functions of the rocker switch
I think it's primary function is to break.
Looks like I've got some inventing to do.
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Re: SWR trace always showing 1:1 as flat line at bottom of screen
Mine also. VNASaver is somewhat more in line with other tools. I''ve been wondering why, too.
Cheers, Ed -KT4ED
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On 2/18/2020 4:46 PM, RetroDude wrote: NanoVNA displays SWR values that are consistently much lower than shown on any of my outboard bridges.
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Re: SWR trace always showing 1:1 as flat line at bottom of screen
I was not sure how to change the scale only for the SWR trace as the other two
traces (Ret-Loss, and Smith) seemed to be working fine CHANNEL, SCALE and FORMAT menus apply only to the most recently selected TRACE
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Re: Anyone had news from Maggie King?
In my alibaba I found this.
Feb. 15, 2020, 03:17:44 PST., the order has been shipped.
So I¡¯ll have to wait.
Best regards,
Robert PA7RG
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Re: SWR trace always showing 1:1 as flat line at bottom of screen
I have not had a flat line problem, but, my NanoVNA displays SWR values that are consistently much lower than shown on any of my outboard bridges.
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Re: SWR trace always showing 1:1 as flat line at bottom of screen
On Tue, Feb 18, 2020 at 09:27 AM, Bill Smotrilla wrote: You may need to use a smaller freq sweep range and select only the bands you
want to sweep individually. The device only has 100 data points of resolution
and a full 30Mhz sweep could easily miss the SWR dips with only 100 data
points. Not sure I am understanding you correctly, but the SWR trace remained flat at the bottom of the screen all the time, there where no dips or peaks of any sort being shown, which is what I would have expected to see, as in fact I know that this multi-band antenna that was being tested has overall quite high SWR across all the ham bands, and that was one of the main reasons that my friend purchased the NanoVNA as he was hoping to make some sense out of the antenna's resonant points, or if there even where any. After the initial 2-35Mhz sweep I switched to a narrower band scan limited to only from 2-10MHz and recalibrated, but the SWR trace was still only flat at the bottom of the screen and the readout was showing 1:1 across the board. I am aware of the 101 data point limitation, but still even with the wider 2-35Mhz initial sweep it should have shown a resolution of about 325Khz which I would think would be more than enough to at least show a good part of the overall varying SWR at the antenna in relation the the frequency sweep. Another theory I had at the time I was playing with the device is that somehow the "signal" going to the SWR trace is too low, and its trace is just somewhere hidden further down on the screen because the scaling is too high, or something to that effect. But I was not sure how to change the scale only for the SWR trace as the other two traces (Ret-Loss, and Smith) seemed to be working fine.
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--- Mit freundlichen Gr¨¹?en Marc Pittorf -----Urspr¨¹ngliche Nachricht----- Von: "Larry Rothman" <nlroth@...> Gesendet: Dienstag, 18. Februar 2020 19:53 An: [email protected]Betreff: Re: [nanovna-users] State save/recall #firmware Why not save it to any of the other 3 or 4 save locations instead of the power-on default? Set up what you want then select calibrate, save, location. To recall, go to recall, location.
On Tuesday, February 18, 2020, 1:44:34 p.m. GMT-5, Nels Nelsen <nels.nelsen@...> wrote: Not being able to save the "state" of the nanoVNA is my #1 dislike. My work around is to save it to "place zero" of recallables as then it will survive on/off .? Once I get set up for a frequency I want to work on I stay there for a week at a time. Nels On Mon, Feb 17, 2020, 10:06 AM <g8kuw@...> wrote: I'm running nanoVNA @edy555 version firmware v0.5.4. Is there the ability
to save the state of the nanoVNA over power cycles? I have the battery
installed, and I can recall 0-4, but not save anything that could be
recalled. Am I missing something? I have only had this for a few days, so
that could be possible.
73 G8KUW
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Why not save it to any of the other 3 or 4 save locations instead of the power-on default?
Set up what you want then select calibrate, save, location.
To recall, go to recall, location.
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On Tuesday, February 18, 2020, 1:44:34 p.m. GMT-5, Nels Nelsen <nels.nelsen@...> wrote: Not being able to save the "state" of the nanoVNA is my #1 dislike. My work around is to save it to "place zero" of recallables as then it will survive on/off .? Once I get set up for a frequency I want to work on I stay there for a week at a time. Nels On Mon, Feb 17, 2020, 10:06 AM <g8kuw@...> wrote: I'm running nanoVNA @edy555 version firmware v0.5.4. Is there the ability
to save the state of the nanoVNA over power cycles? I have the battery
installed, and I can recall 0-4, but not save anything that could be
recalled. Am I missing something? I have only had this for a few days, so
that could be possible.
73 G8KUW
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Re: Android app cable not working!
Here is my Willkac cable working with a Moto X to the nanoVNA. The X is running Android 7 and asks if the nanoVNA should be allowed to use the USB when it is connected. The NanoVNA app just works without fuss. Note that the Wiilkac cable is a standard type A USB 3 socket not type C.
Gary W9TD
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Not being able to save the "state" of the nanoVNA is my #1 dislike.
My work around is to save it to "place zero" of recallables as then it will
survive on/off . Once I get set up for a frequency I want to work on I
stay there for a week at a time.
Nels
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Show quoted text
On Mon, Feb 17, 2020, 10:06 AM <g8kuw@...> wrote: I'm running nanoVNA @edy555 version firmware v0.5.4. Is there the ability
to save the state of the nanoVNA over power cycles? I have the battery
installed, and I can recall 0-4, but not save anything that could be
recalled. Am I missing something? I have only had this for a few days, so
that could be possible.
73 G8KUW
|
Re: Anyone had news from Maggie King?
Go on Alibaba and send her a message from your account. I sent her one last night and she replied this morning.
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Re: Anyone had news from Maggie King?
I placed an order a couple of weeks back for the H4. Just got a shipping notification from alibaba.
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Ohan Smit
DaveH52
Oristo
Gary W9TD
Chris Prosser