Re: Simultaneous S11 and S21 measurements ?
Yes ________________________________ From: [email protected] < [email protected]> on behalf of Neal Pollack <nealix@...> Sent: Monday, February 17, 2020 4:20 PM To: [email protected] < [email protected]> Subject: [nanovna-users] Simultaneous S11 and S21 measurements ? Is the nanovna capable of showing Simultaneous S11 and S21 measurements in one Sweep, like the DG8SAQ VNWA 3EC ? I think I recall something about this requiring two detectors? Beginner. Neal
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Simultaneous S11 and S21 measurements ?
Is the nanovna capable of showing Simultaneous S11 and S21 measurements in one Sweep,
like the DG8SAQ VNWA 3EC ? I think I recall something about this requiring two detectors?
Beginner.
Neal
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Thanks, so the only thing I should do is to multiply the impedance/resistance/reactance values by 6 and they should be correct?
Also looks like the attached picture became very low resolution after uploading. Here are the full screenshots, with marker details:
Cal. 50 ohm:
Cal. 300 ohm:
The antenna should be tuned to around the center of the CCIR FM band, so the 95 MHz match is most likely correct.
I'm not sure what causes the other SWR dips, it's just a regular folded dipole with nothing attached to it. The NanoVNA is right next to it, connected by a piece of PCB with two holes and an SMA connector soldered onto it, like this:
Are these dips present just because it isn't an ideal simulation-like environment?
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Having calibrated to a 300-ohm standard, then why not multiply the measured
value by 6? I believe there is a place in Saver for a multiplier or
arithmetic.
Note in your 300-ohm cal. presentation of the measured data of S11, VSWR,
you show a dip to 1:1 between 41 and 124 MHz (I can not read the closest
labeled point). That also shows extremely near the center of the Smith
Chart. You have placed the marker at this position. Since you have
calibrated with 300 ohms, the center of the chart is now 300 ohms, not
50-ohms. This is also true of your S11, VSWR data measurement.
This practice is quite common when using the Smith Chart. One can
'normalize' the chart center to about anything within the instruments range
of impedances. Many times, we use a 'normalized chart' and represent the
chart center as 1, unity. Then, in working the problem at hand, one
multiples everything presented on the chart by the characteristic
resistance in which one is working - most times, 50-ohms. In your case,
you are working in a 300-ohm system.
Dave - W?LEV
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On Mon, Feb 17, 2020 at 7:17 PM goscickiw <goscickiw@...> wrote: Is there a way to make the NanoVNA show the SWR as close to 1:1 on 300 ohm
antennas when measuring directly without an impedance transformer, while
still showing correct impedance? I need to measure just the antenna, so
that the cables and impedance transformers don't affect the result. I tried
calibrating with 300 ohm load, but then it shows 300 ohms as 50 ohms when
measuring impedance.
Attached example - FM folded dipole readout with NanoVNA calibrated with
50 ohm load, and with 300 ohm load
--
*Dave - W?LEV*
*Just Let Darwin Work*
*Just Think*
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Re: Functions of the rocker switch
Yep, I found this behavior after FW update... rocker switch change ¡°center¡± frequency instead of moving marker.. sometimes works weird on my unit and it drives me crazy...
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Is there a way to make the NanoVNA show the SWR as close to 1:1 on 300 ohm antennas when measuring directly without an impedance transformer, while still showing correct impedance? I need to measure just the antenna, so that the cables and impedance transformers don't affect the result. I tried calibrating with 300 ohm load, but then it shows 300 ohms as 50 ohms when measuring impedance.
Attached example - FM folded dipole readout with NanoVNA calibrated with 50 ohm load, and with 300 ohm load
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Re: Android app cable not working!
As I understand this, if a cable can communicate the phone with a PC, it cannot be used with a phone. A "normal" cable is due for connecting the PC, as a host, with a peripheral, being it a disk, a phone or the nano. For using a phone as a host you must use an "On The Go" cable, that forces the phone to behave as a host, being the other side a disk or the nano to act as the peripheral.
For the guys that uses a TV dongle as a V-UHF receiver connected to a PC, there is an APP that works in a phone and in this case you also need to use an OTG cable.
Regards,
Ignacio EB4APL
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El 17/02/2020 a las 19:06, Kayak escribi¨®: Thank you, I wasn't enabling that flag (didnt see the documentation,
moving too fast and assumed the s/w would provide a dialog about any
settings, my bad)
So the flag is set in the android chrome, confirmed, restarted android
chrome, same error "No compatible devices found". I repeated the
process on a clean LG Aristo 2 phone, same result.
Now do you suppose I should consider a somehow incompatible cable?
Cant really be anything else that I know of. The port communicate with
the pc.
As recommended in the documentation on github (which I would probably
never have found) I ordered a OTG usb-c to usb A adapter cable. Chose
this one, amazon.com/Anker-Adapter-Converts-Technology-Compatible/dp/B01COOQIKU
Thanks for the replies and help. Got to be something simple here...
On Mon, Feb 17, 2020 at 12:21 PM hwalker <herbwalker2476@...> wrote:
On Mon, Feb 17, 2020 at 09:07 AM, Kayak wrote:
I went to your web app online with my samsung (j7 prime) and still "no compatible devices found"
==============================================================
Kayak,
The Samsung (j7 prime) should at least work with the web app online.
These are the developer's instructions from :
1. Enable flag: chrome://flags/#enable-experimental-web-platform-features
2. Access to .
3. Connect your NanoVNA to USB port.
4. Click [CONNECT] and select the device.
- Herb
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Re: Android app cable not working!
On Mon, Feb 17, 2020 at 05:49 PM, hwalker wrote:
On Mon, Feb 17, 2020 at 09:23 AM, Ronan Daly wrote:
" I use a generic unbranded one that came with a chinese tablet and it works
fine with my Galaxy S7."
====================================================================================
Ronan,
Have you tried the NanoVNA app from the Google Play store with your S7?
That would let Kayak know if he might expect the NanoVNA to work off-line with
his j7 prime or not.
- Herb
Yes the app works fine.
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Re: Android app cable not working!
Thank you, I wasn't enabling that flag (didnt see the documentation,
moving too fast and assumed the s/w would provide a dialog about any
settings, my bad)
So the flag is set in the android chrome, confirmed, restarted android
chrome, same error "No compatible devices found". I repeated the
process on a clean LG Aristo 2 phone, same result.
Now do you suppose I should consider a somehow incompatible cable?
Cant really be anything else that I know of. The port communicate with
the pc.
As recommended in the documentation on github (which I would probably
never have found) I ordered a OTG usb-c to usb A adapter cable. Chose
this one, amazon.com/Anker-Adapter-Converts-Technology-Compatible/dp/B01COOQIKU
Thanks for the replies and help. Got to be something simple here...
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On Mon, Feb 17, 2020 at 12:21 PM hwalker <herbwalker2476@...> wrote:
On Mon, Feb 17, 2020 at 09:07 AM, Kayak wrote:
I went to your web app online with my samsung (j7 prime) and still "no compatible devices found"
==============================================================
Kayak,
The Samsung (j7 prime) should at least work with the web app online.
These are the developer's instructions from :
1. Enable flag: chrome://flags/#enable-experimental-web-platform-features
2. Access to .
3. Connect your NanoVNA to USB port.
4. Click [CONNECT] and select the device.
- Herb
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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!
On Mon, Feb 17, 2020 at 09:23 AM, Ronan Daly wrote:
" I use a generic unbranded one that came with a chinese tablet and it works fine with my Galaxy S7."
====================================================================================
Ronan,
Have you tried the NanoVNA app from the Google Play store with your S7? That would let Kayak know if he might expect the NanoVNA to work off-line with his j7 prime or not.
- Herb
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Re: Android app cable not working!
If your phone has a micro usb port then try an adapter like this one
I use a generic unbranded one that came with a chinese tablet and it works fine with my Galaxy S7.
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Re: Android app cable not working!
On Mon, Feb 17, 2020 at 09:07 AM, Kayak wrote:
I went to your web app online with my samsung (j7 prime) and still "no compatible devices found"
==============================================================
Kayak,
The Samsung (j7 prime) should at least work with the web app online.
These are the developer's instructions from :
1. Enable flag: chrome://flags/#enable-experimental-web-platform-features
2. Access to .
3. Connect your NanoVNA to USB port.
4. Click [CONNECT] and select the device.
- Herb
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Re: Android app cable not working!
Thanks Herb I must have missed that. This time, I went to your web app
online with my samsung (j7 prime) and still "no compatible devices
found".. This is the cable (below):
I am not sure what to try next? pretty frustrating, because the phone
screen is much larger and I'd like to make use of it rather than the
nano screen, and the pc (which does connect, just confirmed that now
with nanovna saver) is not portable.
USB C to Micro USB OTG Cable, CableCreation 0.65 ft Type C Braided
Cord, 480Mbps Compatible with MacBook (Pro), Galaxy S8, S9, S10, Pixel
3 XL, 2 XL, Android Devices, 0.2M/ Space Gray
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On Mon, Feb 17, 2020 at 11:36 AM hwalker <herbwalker2476@...> wrote:
On Mon, Feb 17, 2020 at 07:10 AM, Kayak wrote:
" NanoVNA Web App from play store says "no device found" when press connect."
==========================================================
As I warned you in your previous thread, "the apk installation from the Playstore is experimental and may not detect the NanoVNA even if you have the proper cable. The Web client at usually connects and works, but you need to have internet access to use it."
The fact that you were able to download the app from Google Play Store means that your phone meets the version requirements, however; the app is imperfect (read experimental) and some phone models will not connect with it regardless. Short of using the Web client if you have internet access, you either need to change phones (not sure which models are guaranteed to work) or remotely connect using a PC. The app is a free user contribution and he is only able to test it on the configuration he owns. When it works it works, when it doesn't he pretty much responds that it is experimental.
I tried a number of Android phones and tablets with Android version 7 or greater. Most will connect using the Web client but only one android tablet was able to connect using the android app.
- Herb
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Re: Android app cable question
Kayak,
That's one of the ones I got but it didn't work with my phone.
--
Chuck, W5USJ
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Re: Android app cable question
Herb,
That may be the problem I'm having. Tried two different cables and NADA...
My phone is a micro type so I got USB-C to USB-Micro/M
--
Chuck, W5USJ
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Re: Jog wheel switch causes problems
#parts
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Re: Jog wheel switch causes problems
#parts
On Mon, Feb 17, 2020 at 08:25 AM, Leif M wrote:
When I (try to) move a marker on the Nano screen (not PC) the jog wheel switch causes problems. It is too sensitive and starts to change frequency settings.
======================================================================
Leif,
Which firmware do you have loaded? Changing the frequency using the jog switch is a feature using certain firmware, but is disconcerting if you are used to the jog switch changing marker movement.
- Herb
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Re: Android app cable not working!
Hi
When opening your link to the USB cable (s
ee copy below) in the German Amazon store it does NOT state "OTG" capability.
May that's helpful info?
USB C to Micro USB OTG Cable, CableCreation 0.65 ft Type C Braided Cord,
480Mbps Compatible with MacBook (Pro), Galaxy S8, S9, S10, Pixel 3 XL, 2
XL, Android Devices, 0.2M/ Space Gray
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Re: Android app cable not working!
On Mon, Feb 17, 2020 at 07:10 AM, Kayak wrote:
" NanoVNA Web App from play store says "no device found" when press connect."
==========================================================
As I warned you in your previous thread, "the apk installation from the Playstore is experimental and may not detect the NanoVNA even if you have the proper cable. The Web client at usually connects and works, but you need to have internet access to use it."
The fact that you were able to download the app from Google Play Store means that your phone meets the version requirements, however; the app is imperfect (read experimental) and some phone models will not connect with it regardless. Short of using the Web client if you have internet access, you either need to change phones (not sure which models are guaranteed to work) or remotely connect using a PC. The app is a free user contribution and he is only able to test it on the configuration he owns. When it works it works, when it doesn't he pretty much responds that it is experimental.
I tried a number of Android phones and tablets with Android version 7 or greater. Most will connect using the Web client but only one android tablet was able to connect using the android app.
- Herb
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Neal AB6G
goscickiw
Chuck Carpenter