nanovna-users@groups.io

Re: Measure Inductance?

Hi David, but the capacitance of the internal windings of a chip inductor are usually unknown.Of course after you have measured the SRF, you can then calculate it.Kent(I have fought this problem for years with some EW Broadband amps)

Show quoted text

On Sunday, August 15, 2021, 12:41:12 PM CDT, David Eckhardt <davearea51a@...> wrote:  
 
 If you know the capacitor value, calculating the inductance from the
resonance formula is trivial for any calculator.? Just like the Grid Dipper!
? ? ? ? ? 2
? ? ? ? f? ? =? 25330 / (L x C)? ? ? ? ? f in MHz? ? ? ? ? L in
?H? ? ? ? ? ? C in pF

This is easily derived by setting up the requirement for resonance:? XL =
XC? ? and plugging in the appropriate units.

I would propose the inductance measurement would be most meaningful if
measured at the required target frequency.

Dave - W?LEV

On Sun, Aug 15, 2021 at 5:30 PM Joe WB9SBD <nss@...> wrote:

Hi Dave,

Ok I'll try both methods and see if it comes up with different answers.

Now is there anywhere a he he he "Video" or a written step by step etc,
on how to do the smith chart way?

Joe WB9SBD

On 8/15/2021 11:41 AM, David Eckhardt wrote:
Is everything these days a YouTube "presentation".? I'm not knocking what
is presented, as the theory is sound and is rather reminiscent of thesetup
employed when measuring inductance with a grid dip oscillator, but a bit
more accurate.

Any of the NANOs can measure inductance (and capacitance) directly using
the Smith Chart option and the Cursors.? Once calibrated, the inductor is
connected across the source port directly, yes, both center pin and
backshell of the connector.? It will be in parallel with that port.? Once
configured, the value of the real part and the equivalent reactance ofthe
complex port (the inductor) can be easily read in the upper left of the
NANO display.? The NANOs can also be configured to simply display the
reactance of the complex part directly instead of the equivalent value of
the lumped inductor.? Again, just an absolutely wonderful instrumentwhich
compares embarrassingly well to the (expensive) HP/Agilent/Keysite VNAs.

Dave - W?LEV

On Sun, Aug 15, 2021 at 1:59 PM Joe WB9SBD <nss@...> wrote:

I found this video,

It seems like maybe a better way?

Thoughts?

Joe WB9SBD

On 8/15/2021 4:59 AM, Victor Reijs wrote:
I think you need a low frequency to determine the inductance (as sayyou
know).Say between 10kHz and 200kHz? The log(|Z|) curve in a log(Freq)
should go up in a straight line (NanoVNA Saver can provide this logaxis).
All the best,

Victor

Op zo 15 aug. 2021 om 01:29 schreef Bob Albert via groups.io<bob91343=
[email protected]>:

? ? First put an adapter on the SMA connector and set up thecalibration.? Go
to Smith Chart.? Select your frequency range.? Short the test leadsand
see
how much residual inductance there is.? Then connect the unknown.Move
the
marker to whatever frequency you like and it will read out directly.
Bob
? ? ? On Saturday, August 14, 2021, 02:58:37 PM PDT, Joe WB9SBD <nss@...>
wrote:

? ? I have a NanoVNA-H4.
Using this, what is the best accurate way to measure the inductanceof a
coil?

Joe WB9SBD

-- 
*Dave - W?LEV*
*Just Let Darwin Work*

Re: Measure Inductance?

#23973

There is an excellent WIKI on this site.  There is also a beginners guide
to using the NANOVNAs.  There are even a few good YouTube presentation
available in the archives of this site.

Dave - W?LEV

Show quoted text

On Sun, Aug 15, 2021 at 5:40 PM KENT BRITAIN <WA5VJB@...> wrote:

 On very handy reading when making a wide frequency sweep of an
inductor,is that you easily see the jump where the inductor is self
resonance.
You really don't want to use an inductor above it's self resonance
frequency.
It the inductor S.R.F. is say 100 MHz, then above 100 MHz it looks like a
capacitor, not an inductor.
Kent WA5VJB
    On Sunday, August 15, 2021, 12:30:36 PM CDT, Joe WB9SBD <nss@...>
wrote:

 Hi Dave,

Ok I'll try both methods and see if it comes up with different answers.

Now is there anywhere a he he he "Video" or a written step by step etc,
on how to do the smith chart way?

Joe WB9SBD

On 8/15/2021 11:41 AM, David Eckhardt wrote:
Is everything these days a YouTube "presentation".  I'm not knocking what
is presented, as the theory is sound and is rather reminiscent of thesetup
employed when measuring inductance with a grid dip oscillator, but a bit
more accurate.

Any of the NANOs can measure inductance (and capacitance) directly using
the Smith Chart option and the Cursors.  Once calibrated, the inductor is
connected across the source port directly, yes, both center pin and
backshell of the connector.  It will be in parallel with that port.  Once
configured, the value of the real part and the equivalent reactance ofthe
complex port (the inductor) can be easily read in the upper left of the
NANO display.  The NANOs can also be configured to simply display the
reactance of the complex part directly instead of the equivalent value of
the lumped inductor.  Again, just an absolutely wonderful instrumentwhich
compares embarrassingly well to the (expensive) HP/Agilent/KeysiteVNAs.

-- 
*Dave - W?LEV*
*Just Let Darwin Work*

Re: Measure Inductance?

#23972

If you know the capacitor value, calculating the inductance from the
resonance formula is trivial for any calculator.  Just like the Grid Dipper!
          2
        f     =   25330 / (L x C)          f in MHz          L in
?H            C in pF

This is easily derived by setting up the requirement for resonance:  XL =
XC    and plugging in the appropriate units.

I would propose the inductance measurement would be most meaningful if
measured at the required target frequency.

Dave - W?LEV

Show quoted text

On Sun, Aug 15, 2021 at 5:30 PM Joe WB9SBD <nss@...> wrote:

Hi Dave,

Ok I'll try both methods and see if it comes up with different answers.

Now is there anywhere a he he he "Video" or a written step by step etc,
on how to do the smith chart way?

Joe WB9SBD

On 8/15/2021 11:41 AM, David Eckhardt wrote:
Is everything these days a YouTube "presentation".  I'm not knocking what
is presented, as the theory is sound and is rather reminiscent of thesetup
employed when measuring inductance with a grid dip oscillator, but a bit
more accurate.

Any of the NANOs can measure inductance (and capacitance) directly using
the Smith Chart option and the Cursors.  Once calibrated, the inductor is
connected across the source port directly, yes, both center pin and
backshell of the connector.  It will be in parallel with that port.  Once
configured, the value of the real part and the equivalent reactance ofthe
complex port (the inductor) can be easily read in the upper left of the
NANO display.  The NANOs can also be configured to simply display the
reactance of the complex part directly instead of the equivalent value of
the lumped inductor.  Again, just an absolutely wonderful instrumentwhich
compares embarrassingly well to the (expensive) HP/Agilent/Keysite VNAs.

Dave - W?LEV

On Sun, Aug 15, 2021 at 1:59 PM Joe WB9SBD <nss@...> wrote:

I found this video,

It seems like maybe a better way?



Thoughts?

Joe WB9SBD

On 8/15/2021 4:59 AM, Victor Reijs wrote:
I think you need a low frequency to determine the inductance (as sayyou
know).Say between 10kHz and 200kHz? The log(|Z|) curve in a log(Freq)
should go up in a straight line (NanoVNA Saver can provide this logaxis).
All the best,

Victor

Op zo 15 aug. 2021 om 01:29 schreef Bob Albert via groups.io<bob91343=
[email protected]>:

   First put an adapter on the SMA connector and set up thecalibration.  Go
to Smith Chart.  Select your frequency range.  Short the test leadsand
see
how much residual inductance there is.  Then connect the unknown.Move
the
marker to whatever frequency you like and it will read out directly.
Bob
      On Saturday, August 14, 2021, 02:58:37 PM PDT, Joe WB9SBD <nss@...>
wrote:

   I have a NanoVNA-H4.
Using this, what is the best accurate way to measure the inductanceof a
coil?

Joe WB9SBD

-- 
*Dave - W?LEV*
*Just Let Darwin Work*

Re: Measure Inductance?

#23971

On very handy reading when making a wide frequency sweep of an inductor,is that you easily see the jump where the inductor is self resonance.
You really don't want to use an inductor above it's self resonance frequency.
It the inductor S.R.F. is say 100 MHz, then above 100 MHz it looks like a capacitor, not an inductor.
Kent WA5VJB

Show quoted text

On Sunday, August 15, 2021, 12:30:36 PM CDT, Joe WB9SBD <nss@...> wrote:  
 
 Hi Dave,

Ok I'll try both methods and see if it comes up with different answers.

Now is there anywhere a he he he "Video" or a written step by step etc, 
on how to do the smith chart way?

Joe WB9SBD

On 8/15/2021 11:41 AM, David Eckhardt wrote:
Is everything these days a YouTube "presentation".? I'm not knocking what
is presented, as the theory is sound and is rather reminiscent of the setup
employed when measuring inductance with a grid dip oscillator, but a bit
more accurate.

Any of the NANOs can measure inductance (and capacitance) directly using
the Smith Chart option and the Cursors.? Once calibrated, the inductor is
connected across the source port directly, yes, both center pin and
backshell of the connector.? It will be in parallel with that port.? Once
configured, the value of the real part and the equivalent reactance of the
complex port (the inductor) can be easily read in the upper left of the
NANO display.? The NANOs can also be configured to simply display the
reactance of the complex part directly instead of the equivalent value of
the lumped inductor.? Again, just an absolutely wonderful instrument which
compares embarrassingly well to the (expensive) HP/Agilent/Keysite VNAs.

Re: NanoVNA H / H4 / V2 / V2Plus / V2Plus4 firmware v1.0.69 #firmware

#23970

Hmmm. Since the cable type can't be read, we can conjecture that thed.u.t. is old cable or, perhaps, it's cable with an unknown history.
Looking at it with a megger first might be considered.

Johnat radio station VE7AOV.+++++


On 2021-08-14 7:20 a.m., Lou W7HV via groups.io wrote:
Yeah, longer would be better, and there's no need to cut a specific length to make the measurement.  Any reasonable length you have lying around can be used as long as you can measure its physical length with adequate relative accuracy. 1% is good enough.   I've used arbitrary lengths I had on hand ranging from around 10' to over 50'.  (I have a 100' tape measure).  Set the max frequency of the measurement scan range appropriate to the length being measured. Higher for shorter lengths and lower for longer lengths. 

Re: Measuring S11 at input of RF power amplifier - could I calibrate "through" an attenuator?

#23969

Is the tuner between the source and the amp, or between the amp and the load?
But it's telling you more about what impedance the amp likes, not what it really is.
Kent WA5VJB

Show quoted text

On Sunday, August 15, 2021, 12:04:18 PM CDT, Joe <k1ike_mail@...> wrote:  
 
 What about connecting the amplifier to a dummy load thru an antenna 
tuner. Tune for minimum SWR. Then use the Nano to read the impedance of 
the tuner/dummy load?

Joe

Re: Measure Inductance?

#23968

Hi Dave,

Ok I'll try both methods and see if it comes up with different answers.

Now is there anywhere a he he he "Video" or a written step by step etc, on how to do the smith chart way?

Joe WB9SBD

Show quoted text

On 8/15/2021 11:41 AM, David Eckhardt wrote:
Is everything these days a YouTube "presentation".  I'm not knocking what
is presented, as the theory is sound and is rather reminiscent of the setup
employed when measuring inductance with a grid dip oscillator, but a bit
more accurate.

Any of the NANOs can measure inductance (and capacitance) directly using
the Smith Chart option and the Cursors.  Once calibrated, the inductor is
connected across the source port directly, yes, both center pin and
backshell of the connector.  It will be in parallel with that port.  Once
configured, the value of the real part and the equivalent reactance of the
complex port (the inductor) can be easily read in the upper left of the
NANO display.  The NANOs can also be configured to simply display the
reactance of the complex part directly instead of the equivalent value of
the lumped inductor.  Again, just an absolutely wonderful instrument which
compares embarrassingly well to the (expensive) HP/Agilent/Keysite VNAs.

Dave - W?LEV

On Sun, Aug 15, 2021 at 1:59 PM Joe WB9SBD <nss@...> wrote:

I found this video,

It seems like maybe a better way?



Thoughts?

Joe WB9SBD

On 8/15/2021 4:59 AM, Victor Reijs wrote:
I think you need a low frequency to determine the inductance (as say you
know).Say between 10kHz and 200kHz? The log(|Z|) curve in a log(Freq)
should go up in a straight line (NanoVNA Saver can provide this logaxis).
All the best,

Victor

Op zo 15 aug. 2021 om 01:29 schreef Bob Albert via groups.io <bob91343=
[email protected]>:

   First put an adapter on the SMA connector and set up thecalibration.  Go
to Smith Chart.  Select your frequency range.  Short the test leads andsee
how much residual inductance there is.  Then connect the unknown.  Movethe
marker to whatever frequency you like and it will read out directly.
Bob
      On Saturday, August 14, 2021, 02:58:37 PM PDT, Joe WB9SBD <nss@...>
wrote:

   I have a NanoVNA-H4.
Using this, what is the best accurate way to measure the inductance of a
coil?

Joe WB9SBD

Re: Measure Inductance?

#23967

Agree.? Measure it directly.? Using the method in the vid gives the capacitance inductance product, but not the individual values.? You still need to know the value of one of them to measure the value of the other.? Maybe the value printed on the capacitor is good, but it has a tolerance and may be off even more than that.? Plus, the test setup is adding stray capacitance and inductance that further obfuscates what you want to measure. No need to go back to the old grid dip days, except perhaps for nostalgia. 

Agree on YouTubes too.

Show quoted text

On Sunday, August 15, 2021, 10:41:30 AM MDT, David Eckhardt <davearea51a@...> wrote:  
 
 Is everything these days a YouTube "presentation".? I'm not knocking what
is presented, as the theory is sound and is rather reminiscent of the setup
employed when measuring inductance with a grid dip oscillator, but a bit
more accurate.

Any of the NANOs can measure inductance (and capacitance) directly using
the Smith Chart option and the Cursors.? Once calibrated, the inductor is
connected across the source port directly, yes, both center pin and
backshell of the connector.? It will be in parallel with that port.? Once
configured, the value of the real part and the equivalent reactance of the
complex port (the inductor) can be easily read in the upper left of the
NANO display.? The NANOs can also be configured to simply display the
reactance of the complex part directly instead of the equivalent value of
the lumped inductor.? Again, just an absolutely wonderful instrument which
compares embarrassingly well to the (expensive) HP/Agilent/Keysite VNAs.

Dave - W?LEV

On Sun, Aug 15, 2021 at 1:59 PM Joe WB9SBD <nss@...> wrote:

I found this video,

It seems like maybe a better way?

Thoughts?

Joe WB9SBD

On 8/15/2021 4:59 AM, Victor Reijs wrote:
I think you need a low frequency to determine the inductance (as say you
know).Say between 10kHz and 200kHz? The log(|Z|) curve in a log(Freq)
should go up in a straight line (NanoVNA Saver can provide this logaxis).

All the best,

Victor

Op zo 15 aug. 2021 om 01:29 schreef Bob Albert via groups.io <bob91343=
[email protected]>:

? First put an adapter on the SMA connector and set up thecalibration.? Go
to Smith Chart.? Select your frequency range.? Short the test leads andsee
how much residual inductance there is.? Then connect the unknown.? Movethe
marker to whatever frequency you like and it will read out directly.
Bob
? ? ? On Saturday, August 14, 2021, 02:58:37 PM PDT, Joe WB9SBD <nss@...>
wrote:

? I have a NanoVNA-H4.
Using this, what is the best accurate way to measure the inductance of a
coil?

Joe WB9SBD

-- 
*Dave - W?LEV*
*Just Let Darwin Work*

Re: Measuring S11 at input of RF power amplifier - could I calibrate "through" an attenuator?

#23966

What about connecting the amplifier to a dummy load thru an antenna tuner. Tune for minimum SWR. Then use the Nano to read the impedance of the tuner/dummy load?

Joe

Re: Measure Inductance?

#23965

Is everything these days a YouTube "presentation".  I'm not knocking what
is presented, as the theory is sound and is rather reminiscent of the setup
employed when measuring inductance with a grid dip oscillator, but a bit
more accurate.

Any of the NANOs can measure inductance (and capacitance) directly using
the Smith Chart option and the Cursors.  Once calibrated, the inductor is
connected across the source port directly, yes, both center pin and
backshell of the connector.  It will be in parallel with that port.  Once
configured, the value of the real part and the equivalent reactance of the
complex port (the inductor) can be easily read in the upper left of the
NANO display.  The NANOs can also be configured to simply display the
reactance of the complex part directly instead of the equivalent value of
the lumped inductor.  Again, just an absolutely wonderful instrument which
compares embarrassingly well to the (expensive) HP/Agilent/Keysite VNAs.

Dave - W?LEV

Show quoted text

On Sun, Aug 15, 2021 at 1:59 PM Joe WB9SBD <nss@...> wrote:

I found this video,

It seems like maybe a better way?



Thoughts?

Joe WB9SBD

On 8/15/2021 4:59 AM, Victor Reijs wrote:
I think you need a low frequency to determine the inductance (as say you
know).Say between 10kHz and 200kHz? The log(|Z|) curve in a log(Freq)
should go up in a straight line (NanoVNA Saver can provide this logaxis).

All the best,

Victor

Op zo 15 aug. 2021 om 01:29 schreef Bob Albert via groups.io <bob91343=
[email protected]>:

  First put an adapter on the SMA connector and set up thecalibration.  Go
to Smith Chart.  Select your frequency range.  Short the test leads andsee
how much residual inductance there is.  Then connect the unknown.  Movethe
marker to whatever frequency you like and it will read out directly.
Bob
     On Saturday, August 14, 2021, 02:58:37 PM PDT, Joe WB9SBD <nss@...>
wrote:

  I have a NanoVNA-H4.
Using this, what is the best accurate way to measure the inductance of a
coil?

Joe WB9SBD

-- 
*Dave - W?LEV*
*Just Let Darwin Work*

Re: Measuring S11 at input of RF power amplifier - could I calibrate "through" an attenuator?

#23964

While an interesting measurement, unless the amp is powered, the characteristics of the active device will be way off.
Now when powered (A learning experience from years ago) there will be quite a bit of white noise generated by the active device.? ?This noise added to the actual reflected signal results in Input Return GAIN.? Not loss.? ? The VNA sees the circuit as a reflection amplifier.? Shades of Parametric Amps from the early days of Radio Astronomy.? ? ??
I'm afraid the NanoVNA just isn't the tool for this job.? ? Kent WA5VJB

Show quoted text

On Sunday, August 15, 2021, 08:57:36 AM CDT, eyecue_two@... <eyecue_two@...> wrote:  
 
 IT would help to know what amp you are looking into with the Nano.? I have been able to check and tune mine with the power off by manually closing the keying circuit

Re: Measure Inductance?

#23963

I found this video,

It seems like maybe a better way?

Thoughts?

Joe WB9SBD

Show quoted text

On 8/15/2021 4:59 AM, Victor Reijs wrote:
I think you need a low frequency to determine the inductance (as say you
know).Say between 10kHz and 200kHz? The log(|Z|) curve in a log(Freq)
should go up in a straight line (NanoVNA Saver can provide this log axis).

All the best,

Victor

Op zo 15 aug. 2021 om 01:29 schreef Bob Albert via groups.io <bob91343=
[email protected]>:

  First put an adapter on the SMA connector and set up the calibration.  Go
to Smith Chart.  Select your frequency range.  Short the test leads and see
how much residual inductance there is.  Then connect the unknown.  Move the
marker to whatever frequency you like and it will read out directly.
Bob
     On Saturday, August 14, 2021, 02:58:37 PM PDT, Joe WB9SBD <nss@...>
wrote:

  I have a NanoVNA-H4.
Using this, what is the best accurate way to measure the inductance of a
coil?

Joe WB9SBD

Re: Measuring S11 at input of RF power amplifier - could I calibrate "through" an attenuator?

#23962

IT would help to know what amp you are looking into with the Nano.  I have been able to check and tune mine with the power off by manually closing the keying circuit

Re: download the calibration from the NanoVNA

#23961

But this internal calibrstion format

Re: download the calibration from the NanoVNA

#23960

Use console data command
data 2
data 3
....
data 6

download the calibration from the NanoVNA

#23959

Hallo all of you,

Do you know if it is possible to download the calibration files from the
naanoVNA to the NanoVNA Saver? I understand NanoSave Saver can use the
device (NanaVNA) calibration...  . I would like to be able to save that
device calibration file from the NanoVNA Saver (which looks not to be
possible it seems...)?

Any help is welcome. Thanks.

All the best,

Victor

Re: Measure Inductance?

#23958

I think you need a low frequency to determine the inductance (as say you
know).Say between 10kHz and 200kHz? The log(|Z|) curve in a log(Freq)
should go up in a straight line (NanoVNA Saver can provide this log axis).

All the best,

Victor

Op zo 15 aug. 2021 om 01:29 schreef Bob Albert via groups.io <bob91343=
[email protected]>:

Show quoted text

 First put an adapter on the SMA connector and set up the calibration.  Go
to Smith Chart.  Select your frequency range.  Short the test leads and see
how much residual inductance there is.  Then connect the unknown.  Move the
marker to whatever frequency you like and it will read out directly.
Bob
    On Saturday, August 14, 2021, 02:58:37 PM PDT, Joe WB9SBD <nss@...>
wrote:

 I have a NanoVNA-H4.
Using this, what is the best accurate way to measure the inductance of a
coil?

Joe WB9SBD

Re: NanoVNA H / H4 / V2 / V2Plus / V2Plus4 firmware v1.0.69 #firmware

#23957

I remove first message, for download last firmware need use file section
/g/nanovna-users/files/Dislord%27s%20Nanovna%20-H%20Firmware

Note: firmware pack contain zip archive for H/H4/V2/V2plus/V2Plus4 devices. For V2 series also for different display size 2.8/3.5 inch need use 320x240, for 4 inch 480x320, all V2 formware build for disabled FPU

Re: Measure Inductance?

Bob Albert

#23956

First put an adapter on the SMA connector and set up the calibration.? Go to Smith Chart.? Select your frequency range.? Short the test leads and see how much residual inductance there is.? Then connect the unknown.? Move the marker to whatever frequency you like and it will read out directly.
Bob

Show quoted text

On Saturday, August 14, 2021, 02:58:37 PM PDT, Joe WB9SBD <nss@...> wrote:  
 
 I have a NanoVNA-H4.
Using this, what is the best accurate way to measure the inductance of a 
coil?

Joe WB9SBD

Re: danger measuring antenna

#23955

Dave:  That choke also serves another very important function; it will short the plate supply to ground if the anode coupling capacitor should suffer from leakage current or fail short, keeping you from impressing plate voltage onto your antenna and whatever else is attached to the output terminal.
73, Don N2VGU.

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