开云体育

Who can increase the font size in the firmware?

Radu,
Please note there is a big difference between upper case C and lower case c as an indication of calibration.?
Refer to the User Guide in the Forum files section. I emphasized this in the section on calibration.?
If you see c0 instead of C0 then the unit is NOT calibrated. (The number can be 0 thru 4)
Remember to always press the Reset menu button before calibration and then Save to one of the memories ( 0 is the power-on recall default memory).?



On Sat, 23 May 2020 at 10:29 PM, Radu Bogdan Dicher<vondicher@...> wrote: Larry,
Thank you for your input. When I run the scan, I see "c1" on the top/left
side, and I'm always keeping it current.
That said, I just tried in both modes - RECALL 0, and RECALL 1 - and I
can't see a difference in the graph shape. Maybe my calibration hasn't been
successful?... Or, maybe this is a sign the device is defective?
Thank you,
Radu.


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On Sat, May 23, 2020 at 4:04 PM Larry Rothman <nlroth@...> wrote:

Please remember that if even if you've saved your new calibration to c1,
if you power cycle the Nano, it automatically recalls c0 and you need to
manually recall c1 every time you turn the unit ON

On top of that, many Nano units will power cycle when connected to USB
power.


? On Sat, 23 May 2020 at 6:56 PM, Radu Bogdan Dicher<vondicher@...>
wrote:? Just to document this a bit better - I placed my calibration data
on "c1,"
which I'm recalling (and I see on the left side of the screen, on top)
before running measurements. I calibrated for a CENTER of 10.7MHz, and a
SPAN of 1.4MHz. This was done with the cables in place, including the patch
extension (per guidelines), but my little kit that allows me to socket the
filters was not connected during calibration (I came to wonder if I should
do that).

To continue establishing the baseline of my setup, the kit has proper
termination for the filters (~330ohm) and cables (~50ohm), and also a 10pF
cap on the filters output (per Murata datasheet).


<

Virus-free.
www.avg.com
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<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

On Sat, May 23, 2020 at 3:29 PM Radu Bogdan Dicher via groups.io
<vondicher=
[email protected]> wrote:

Hi all,
Having some confidence I've completed calibration on the band of interest
to me (I think I did 10MHz to 11MHz), I am getting the same titled scan

of

pretty much any number of filters I threw at this (I enclose a sample). I
am not sure if I need to return this, or request a replacement some other
way.
I contacted the seller (R&L), but it doesn't look like they have stock at
all and they haven't had any in a while.
[image: image.png]
Thank you all for you input.
Radu.

<

Virus-free.
www.avg.com
<

<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

On Wed, May 6, 2020 at 8:23 PM Radu Bogdan Dicher via groups.io
<vondicher=
[email protected]> wrote:

I think I figured it, a bit trial and error and such. The idea seems to

be

to turn off two traces out of four and make sure the two left follow
certain inputs (LOGMAG for each CH). Past this step, it's a bit weird

how

the calibration menu steps one ahead on you, making it a bit confusing

as

to whether it completed the previous step or not. But it seems the

traces

settle in a way that tells me the device read "itself" and calibrated
accordingly.

I'm repeating the procedure, as my 10.7MHz filters plots still lean

lower

on the left side. This is across multiple filters, can't be due to

them,

still think it's the device.

On Wed, May 6, 2020 at 7:41 PM Radu Bogdan Dicher via groups.io
<vondicher=
[email protected]> wrote:

I'm at the start of the calibration procedure, and I've connected

both

cables on CH0 and CH1, while using the pass-through attachment ("F-F

SMA"

in the v1.1 guidelines, in my interpretation) on the other end of the

SMA

cable coming from CH0.

The menu steps are clear until step 4, which calls for a "4. SINGLE."

I'm

not sure what this is. I don't see it anywhere following/around

TRACE 0

(which is there). I wonder if this is due to recent changes in the

menu

structure. Or maybe I am just missing something...

Thank you all for your help.
Radu.

On Tue, May 5, 2020 at 7:14 PM Radu Bogdan Dicher via groups.io
<vondicher=
[email protected]> wrote:

Thank you all.

Firstly - on the attachments. Paul: I guess by elimination works

great!

;)

In fact, makes complete sense and thank you.

Secondly - on the filters. Jim: yes, I am terminating the measuring

rig

properly by impedance matching (closest possible to 330ohm to

filters

and

50ohm to the NanoVNA). Even after eliminating unnecessary
complications (50ohm BNC cables, SMA adapters, etc.), the filters

response

is still screwy (though much improved), and this is across multiple
filters. I assume next step on this pursuit is to recalibrate. I

assume

this is probably about as good as factory calibration, so there's

not

much

to loose there.

Thirdly - on the manuals/files: Thank you for that repository, I

wasn't

aware of it!

Radu.

On Tue, May 5, 2020 at 6:37 PM Jim Allyn - N7JA <

jim@...>

wrote:

If the filters are not properly impedance matched, they will not

be

symmetrical.? In fact, the passband may be horribly distorted

compared

to

what you expect.? Further, the group delay of the filter will be

screwy,

which is important to those going for minimum distortion in their

FM

receivers.

<

Virus-free.
www.avg.com
<

<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

<

Virus-free.
www.avg.com
<

<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

<>
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www.avg.com
<>
<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

Hello,

You still need to compile it, but I have attached a nanovna-SAVER release that its compatible with the V2 and H4, with the addition of a small form
where one can add "attenuation" threshold to S21, courtesy from user @gaionim .

Luis, CT2FZI

Update NanoVNA H4 firmware to v0.9.1 beta

Work around errors in SD card support:

Cleanup my SD card support code
Implement read/write data CRC16 check
Implement command CRC7 check
Fix SPI bus problems
Enable support short and long filenames

Now firmware have beta status and look stable (at this time no errors on read/write on my test card while made 100 screenshots)
Debug console log still present, need for support

I measured the CW frequency error during "my" NanoVNA warm-up.

Without the DiSlord's installed FW, the actual error would be shifted higher !

May be not a TCXO but XO as i wrote in a past message.

Error during assembly ? Cost reason ? They are just assumptions.

Rudi

PS As i don't have a temperature sensor to measure the internal

closed NanoVNA-H value, i'v just measured the elapsed time since power-up.

(Sorry for my English language)

Looks like it's on its way into Hugen's NanoVNA-H:



Just checked my NanoVNA-H Feb 21 2020 firmware and i don't see that menu
yet.



Thanks,

Chris.

On Sun, May 24, 2020 at 12:29 PM Chris Keladis via groups.io <ckeladis=
[email protected]> wrote:

Thanks Larry, will submit there.



Chris.

On Sun, 24 May 2020, 11:57 am Larry Rothman, <nlroth@...> wrote:

A much better place for feature requests is in the GitHub repo for the
individual developers where it can be commented on and tracked.



On Sat, 23 May 2020 at 9:05 PM, Chris Keladis<ckeladis@...>
wrote: Was just reading about Reald's "big font overlay" feature from

his

firmware, looks something like this:

[image: image.png]

This is great to have as a standard feature in all firmwares. Would also

be

useful on 4" displays as well.

I know Hugen and others are on the list so just wanted to submit this as

a

feature request ::)




Thanks,

Chris.

Larry,
Thank you for your input. When I run the scan, I see "c1" on the top/left
side, and I'm always keeping it current.
That said, I just tried in both modes - RECALL 0, and RECALL 1 - and I
can't see a difference in the graph shape. Maybe my calibration hasn't been
successful?... Or, maybe this is a sign the device is defective?
Thank you,
Radu.


<>
Virus-free.
www.avg.com
<>
<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

On Sat, May 23, 2020 at 4:04 PM Larry Rothman <nlroth@...> wrote:

Please remember that if even if you've saved your new calibration to c1,
if you power cycle the Nano, it automatically recalls c0 and you need to
manually recall c1 every time you turn the unit ON

On top of that, many Nano units will power cycle when connected to USB
power.


On Sat, 23 May 2020 at 6:56 PM, Radu Bogdan Dicher<vondicher@...>
wrote: Just to document this a bit better - I placed my calibration data
on "c1,"
which I'm recalling (and I see on the left side of the screen, on top)
before running measurements. I calibrated for a CENTER of 10.7MHz, and a
SPAN of 1.4MHz. This was done with the cables in place, including the patch
extension (per guidelines), but my little kit that allows me to socket the
filters was not connected during calibration (I came to wonder if I should
do that).

To continue establishing the baseline of my setup, the kit has proper
termination for the filters (~330ohm) and cables (~50ohm), and also a 10pF
cap on the filters output (per Murata datasheet).


<

Virus-free.
www.avg.com
<

<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

On Sat, May 23, 2020 at 3:29 PM Radu Bogdan Dicher via groups.io
<vondicher=
[email protected]> wrote:

Hi all,
Having some confidence I've completed calibration on the band of interest
to me (I think I did 10MHz to 11MHz), I am getting the same titled scan

of

pretty much any number of filters I threw at this (I enclose a sample). I
am not sure if I need to return this, or request a replacement some other
way.
I contacted the seller (R&L), but it doesn't look like they have stock at
all and they haven't had any in a while.
[image: image.png]
Thank you all for you input.
Radu.

<

Virus-free.
www.avg.com
<

<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

On Wed, May 6, 2020 at 8:23 PM Radu Bogdan Dicher via groups.io
<vondicher=
[email protected]> wrote:

I think I figured it, a bit trial and error and such. The idea seems to

be

to turn off two traces out of four and make sure the two left follow
certain inputs (LOGMAG for each CH). Past this step, it's a bit weird

how

the calibration menu steps one ahead on you, making it a bit confusing

as

to whether it completed the previous step or not. But it seems the

traces

settle in a way that tells me the device read "itself" and calibrated
accordingly.

I'm repeating the procedure, as my 10.7MHz filters plots still lean

lower

on the left side. This is across multiple filters, can't be due to

them,

still think it's the device.

On Wed, May 6, 2020 at 7:41 PM Radu Bogdan Dicher via groups.io
<vondicher=
[email protected]> wrote:

I'm at the start of the calibration procedure, and I've connected

both

cables on CH0 and CH1, while using the pass-through attachment ("F-F

SMA"

in the v1.1 guidelines, in my interpretation) on the other end of the

SMA

cable coming from CH0.

The menu steps are clear until step 4, which calls for a "4. SINGLE."

I'm

not sure what this is. I don't see it anywhere following/around

TRACE 0

(which is there). I wonder if this is due to recent changes in the

menu

structure. Or maybe I am just missing something...

Thank you all for your help.
Radu.

On Tue, May 5, 2020 at 7:14 PM Radu Bogdan Dicher via groups.io
<vondicher=
[email protected]> wrote:

Thank you all.

Firstly - on the attachments. Paul: I guess by elimination works

great!

;)

In fact, makes complete sense and thank you.

Secondly - on the filters. Jim: yes, I am terminating the measuring

rig

properly by impedance matching (closest possible to 330ohm to

filters

and

50ohm to the NanoVNA). Even after eliminating unnecessary
complications (50ohm BNC cables, SMA adapters, etc.), the filters

response

is still screwy (though much improved), and this is across multiple
filters. I assume next step on this pursuit is to recalibrate. I

assume

this is probably about as good as factory calibration, so there's

not

much

to loose there.

Thirdly - on the manuals/files: Thank you for that repository, I

wasn't

aware of it!

Radu.

On Tue, May 5, 2020 at 6:37 PM Jim Allyn - N7JA <

jim@...>

wrote:

If the filters are not properly impedance matched, they will not

be

symmetrical. In fact, the passband may be horribly distorted

compared

to

what you expect. Further, the group delay of the filter will be

screwy,

which is important to those going for minimum distortion in their

FM

receivers.

<

Virus-free.
www.avg.com
<

<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

<

Virus-free.
www.avg.com
<

<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

<>
Virus-free.
www.avg.com
<>
<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

Thanks Larry, will submit there.



Chris.

A much better place for feature requests is in the GitHub repo for the individual developers where it can be commented on and tracked.?



On Sat, 23 May 2020 at 9:05 PM, Chris Keladis<ckeladis@...> wrote: Was just reading about Reald's "big font overlay" feature from his
firmware, looks something like this:

[image: image.png]

This is great to have as a standard feature in all firmwares. Would also be
useful on 4" displays as well.

I know Hugen and others are on the list so just wanted to submit this as a
feature request ::)




Thanks,

Chris.

Was just reading about Reald's "big font overlay" feature from his
firmware, looks something like this:

[image: image.png]

This is great to have as a standard feature in all firmwares. Would also be
useful on 4" displays as well.

I know Hugen and others are on the list so just wanted to submit this as a
feature request ::)




Thanks,

Chris.

Please remember that if even if you've saved your new calibration to c1, if you power cycle the Nano, it automatically recalls c0 and you need to manually recall c1 every time you turn the unit ON

On top of that, many Nano units will power cycle when connected to USB power.?


On Sat, 23 May 2020 at 6:56 PM, Radu Bogdan Dicher<vondicher@...> wrote: Just to document this a bit better - I placed my calibration data on "c1,"
which I'm recalling (and I see on the left side of the screen, on top)
before running measurements. I calibrated for a CENTER of 10.7MHz, and a
SPAN of 1.4MHz. This was done with the cables in place, including the patch
extension (per guidelines), but my little kit that allows me to socket the
filters was not connected during calibration (I came to wonder if I should
do that).

To continue establishing the baseline of my setup, the kit has proper
termination for the filters (~330ohm) and cables (~50ohm), and also a 10pF
cap on the filters output (per Murata datasheet).


<>
Virus-free.
www.avg.com
<>
<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

On Sat, May 23, 2020 at 3:29 PM Radu Bogdan Dicher via groups.io <vondicher=
[email protected]> wrote:

Hi all,
Having some confidence I've completed calibration on the band of interest
to me (I think I did 10MHz to 11MHz), I am getting the same titled scan of
pretty much any number of filters I threw at this (I enclose a sample). I
am not sure if I need to return this, or request a replacement some other
way.
I contacted the seller (R&L), but it doesn't look like they have stock at
all and they haven't had any in a while.
[image: image.png]
Thank you all for you input.
Radu.

<

Virus-free.
www.avg.com
<

<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

On Wed, May 6, 2020 at 8:23 PM Radu Bogdan Dicher via groups.io
<vondicher=
[email protected]> wrote:

I think I figured it, a bit trial and error and such. The idea seems to

be

to turn off two traces out of four and make sure the two left follow
certain inputs (LOGMAG for each CH). Past this step, it's a bit weird how
the calibration menu steps one ahead on you, making it a bit confusing as
to whether it completed the previous step or not. But it seems the traces
settle in a way that tells me the device read "itself" and calibrated
accordingly.

I'm repeating the procedure, as my 10.7MHz filters plots still lean lower
on the left side. This is across multiple filters, can't be due to them,
still think it's the device.

On Wed, May 6, 2020 at 7:41 PM Radu Bogdan Dicher via groups.io
<vondicher=
[email protected]> wrote:

I'm at the start of the calibration procedure, and I've connected both
cables on CH0 and CH1, while using the pass-through attachment ("F-F

SMA"

in the v1.1 guidelines, in my interpretation) on the other end of the

SMA

cable coming from CH0.

The menu steps are clear until step 4, which calls for a "4. SINGLE."

I'm

not sure what this is. I don't see it anywhere following/around TRACE 0
(which is there). I wonder if this is due to recent changes in the menu
structure. Or maybe I am just missing something...

Thank you all for your help.
Radu.

On Tue, May 5, 2020 at 7:14 PM Radu Bogdan Dicher via groups.io
<vondicher=
[email protected]> wrote:

Thank you all.

Firstly - on the attachments. Paul: I guess by elimination works

great!

;)

In fact, makes complete sense and thank you.

Secondly - on the filters. Jim: yes, I am terminating the measuring

rig

properly by impedance matching (closest possible to 330ohm to filters

and

50ohm to the NanoVNA). Even after eliminating unnecessary
complications (50ohm BNC cables, SMA adapters, etc.), the filters

response

is still screwy (though much improved), and this is across multiple
filters. I assume next step on this pursuit is to recalibrate. I

assume

this is probably about as good as factory calibration, so there's not

much

to loose there.

Thirdly - on the manuals/files: Thank you for that repository, I

wasn't

aware of it!

Radu.

On Tue, May 5, 2020 at 6:37 PM Jim Allyn - N7JA <

jim@...>

wrote:

If the filters are not properly impedance matched, they will not be
symmetrical.? In fact, the passband may be horribly distorted

compared

to

what you expect.? Further, the group delay of the filter will be

screwy,

which is important to those going for minimum distortion in their

FM

receivers.

<

Virus-free.
www.avg.com
<

<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

<>
Virus-free.
www.avg.com
<>
<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

Just to document this a bit better - I placed my calibration data on "c1,"
which I'm recalling (and I see on the left side of the screen, on top)
before running measurements. I calibrated for a CENTER of 10.7MHz, and a
SPAN of 1.4MHz. This was done with the cables in place, including the patch
extension (per guidelines), but my little kit that allows me to socket the
filters was not connected during calibration (I came to wonder if I should
do that).

To continue establishing the baseline of my setup, the kit has proper
termination for the filters (~330ohm) and cables (~50ohm), and also a 10pF
cap on the filters output (per Murata datasheet).


<>
Virus-free.
www.avg.com
<>
<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

On Sat, May 23, 2020 at 3:29 PM Radu Bogdan Dicher via groups.io <vondicher=
[email protected]> wrote:

Hi all,
Having some confidence I've completed calibration on the band of interest
to me (I think I did 10MHz to 11MHz), I am getting the same titled scan of
pretty much any number of filters I threw at this (I enclose a sample). I
am not sure if I need to return this, or request a replacement some other
way.
I contacted the seller (R&L), but it doesn't look like they have stock at
all and they haven't had any in a while.
[image: image.png]
Thank you all for you input.
Radu.

<

Virus-free.
www.avg.com
<

<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

On Wed, May 6, 2020 at 8:23 PM Radu Bogdan Dicher via groups.io
<vondicher=
[email protected]> wrote:

I think I figured it, a bit trial and error and such. The idea seems to

be

to turn off two traces out of four and make sure the two left follow
certain inputs (LOGMAG for each CH). Past this step, it's a bit weird how
the calibration menu steps one ahead on you, making it a bit confusing as
to whether it completed the previous step or not. But it seems the traces
settle in a way that tells me the device read "itself" and calibrated
accordingly.

I'm repeating the procedure, as my 10.7MHz filters plots still lean lower
on the left side. This is across multiple filters, can't be due to them,
still think it's the device.

On Wed, May 6, 2020 at 7:41 PM Radu Bogdan Dicher via groups.io
<vondicher=
[email protected]> wrote:

I'm at the start of the calibration procedure, and I've connected both
cables on CH0 and CH1, while using the pass-through attachment ("F-F

SMA"

in the v1.1 guidelines, in my interpretation) on the other end of the

SMA

cable coming from CH0.

The menu steps are clear until step 4, which calls for a "4. SINGLE."

I'm

not sure what this is. I don't see it anywhere following/around TRACE 0
(which is there). I wonder if this is due to recent changes in the menu
structure. Or maybe I am just missing something...

Thank you all for your help.
Radu.

On Tue, May 5, 2020 at 7:14 PM Radu Bogdan Dicher via groups.io
<vondicher=
[email protected]> wrote:

Thank you all.

Firstly - on the attachments. Paul: I guess by elimination works

great!

;)

In fact, makes complete sense and thank you.

Secondly - on the filters. Jim: yes, I am terminating the measuring

rig

properly by impedance matching (closest possible to 330ohm to filters

and

50ohm to the NanoVNA). Even after eliminating unnecessary
complications (50ohm BNC cables, SMA adapters, etc.), the filters

response

is still screwy (though much improved), and this is across multiple
filters. I assume next step on this pursuit is to recalibrate. I

assume

this is probably about as good as factory calibration, so there's not

much

to loose there.

Thirdly - on the manuals/files: Thank you for that repository, I

wasn't

aware of it!

Radu.

On Tue, May 5, 2020 at 6:37 PM Jim Allyn - N7JA <

jim@...>

wrote:

If the filters are not properly impedance matched, they will not be
symmetrical. In fact, the passband may be horribly distorted

compared

to

what you expect. Further, the group delay of the filter will be

screwy,

which is important to those going for minimum distortion in their

FM

receivers.

<

Virus-free.
www.avg.com
<

<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

<>
Virus-free.
www.avg.com
<>
<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

Hi all,
Having some confidence I've completed calibration on the band of interest
to me (I think I did 10MHz to 11MHz), I am getting the same titled scan of
pretty much any number of filters I threw at this (I enclose a sample). I
am not sure if I need to return this, or request a replacement some other
way.
I contacted the seller (R&L), but it doesn't look like they have stock at
all and they haven't had any in a while.
[image: image.png]
Thank you all for you input.
Radu.

<>
Virus-free.
www.avg.com
<>
<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

On Wed, May 6, 2020 at 8:23 PM Radu Bogdan Dicher via groups.io <vondicher=
[email protected]> wrote:

I think I figured it, a bit trial and error and such. The idea seems to be
to turn off two traces out of four and make sure the two left follow
certain inputs (LOGMAG for each CH). Past this step, it's a bit weird how
the calibration menu steps one ahead on you, making it a bit confusing as
to whether it completed the previous step or not. But it seems the traces
settle in a way that tells me the device read "itself" and calibrated
accordingly.

I'm repeating the procedure, as my 10.7MHz filters plots still lean lower
on the left side. This is across multiple filters, can't be due to them,
still think it's the device.

On Wed, May 6, 2020 at 7:41 PM Radu Bogdan Dicher via groups.io
<vondicher=
[email protected]> wrote:

I'm at the start of the calibration procedure, and I've connected both
cables on CH0 and CH1, while using the pass-through attachment ("F-F SMA"
in the v1.1 guidelines, in my interpretation) on the other end of the SMA
cable coming from CH0.

The menu steps are clear until step 4, which calls for a "4. SINGLE." I'm
not sure what this is. I don't see it anywhere following/around TRACE 0
(which is there). I wonder if this is due to recent changes in the menu
structure. Or maybe I am just missing something...

Thank you all for your help.
Radu.

On Tue, May 5, 2020 at 7:14 PM Radu Bogdan Dicher via groups.io
<vondicher=
[email protected]> wrote:

Thank you all.

Firstly - on the attachments. Paul: I guess by elimination works great!

;)

In fact, makes complete sense and thank you.

Secondly - on the filters. Jim: yes, I am terminating the measuring rig
properly by impedance matching (closest possible to 330ohm to filters

and

50ohm to the NanoVNA). Even after eliminating unnecessary
complications (50ohm BNC cables, SMA adapters, etc.), the filters

response

is still screwy (though much improved), and this is across multiple
filters. I assume next step on this pursuit is to recalibrate. I assume
this is probably about as good as factory calibration, so there's not

much

to loose there.

Thirdly - on the manuals/files: Thank you for that repository, I wasn't
aware of it!

Radu.

On Tue, May 5, 2020 at 6:37 PM Jim Allyn - N7JA <

jim@...>

wrote:

If the filters are not properly impedance matched, they will not be
symmetrical. In fact, the passband may be horribly distorted

compared

to

what you expect. Further, the group delay of the filter will be

screwy,

which is important to those going for minimum distortion in their FM
receivers.

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I purchased the H4 from Alibaba. I'm very satisfied. It was $70 USD delivered in less than a month.

The vendor was recomended by a microwave group I'm a member of.

?___
Sent from my two way wrist watch
73 de W3AB/GEO?

I am looking for a nanoVNA that will cover 23cms band and has a larger screen that my old eyes can see :-(
At the moment, there are several Ebay sellers offering what appears to be the 4" screen 1.5GHz version of the nanoVNA at a very attractive price? (attached screen grab)
The pictured device claims to be a 4.2 Version (I assume they mean firmware?) so seems pretty current?
However they call it an Antenna Network Analyser rather than VNA.
I am sure I read on this group that when upgrading the firmware there is VNA, and a separate Antenna Analyser firmware.
Also there is a spelling mistake in the on-screen menu :- MARKER is spelled MARKEY leading me to suspect it is a clone?
I would welcome all your experienced advice and advice please :-

1) Has anyone purchased one of these devices recently off Ebay ?
2) Is it running the full VNA firmware ie. Logmag, Phase, Delay, Smith, SWR, etc?
3) Does it have the full input screening?
4) is it a Hugen device or a clone?
5) how well does it work at 1296MHz

Having bought a cheap nanoVNA only to discover is was rated as a BAD clone on this forum (and spent today adding screening cans to 'tame' the input noise), I thought I had better get some advice from you before making the same mistake again.
Thanks in anticipation.....
Dave

I agree with you. My problem was how to modify this ratio into the NanoVNA firmware; thanks to DiSlord, who modified the code with "my" oscillator value and giving to me the modified dfu file,

i was able to upgrade my NanoVNA with this file and get a very acceptable 1 ppm error instead of the previous -85.5 ppm.

Hello Dave,
The screen shots you appended show just a quarter of thr screen.
I think you wanted to append the whole screen size of the nanoVNA.
I thought you have already seen that.
73, Rudi DL5FA

Hi Rudi what did you wish to know?
My nanoVNA was the 'BAD' clone without screening cans over the input stages
and exhibited unwanted vectors due to noise pickup when is Smith Chart mode.
Since adding the cans the noise is cured :-)
Dave

That's the method HP uses in a lot of their gear. They use a very stable TCXO and to calibrate the frequency you change the divide by ratio. On my 8920 to calibrate the frequency you input a 10MHz frequency from a standard (GPS or whatever) and it compares the 2 and then changes the divide by on the internal oscillator (which doesn't run at 10 MHz) to match the reference. Very easy this way, no tweaking.

Why not ?

As i want to replace my oscillator in the future, a good idea

to reverse to a new value !

Thank you one more time and all the best.

Rudi