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Re: How find crystal filter terminaison resistor and capacitor

 

Thanks for this comment Gerard.

I upgraded to from DiSlord 1.1 to DiSlord 1.2.00 on an H4.3 and it seems to work.
I tried 300 ohm as Zo and it moved the 50 ohm load to the place it should be on a 300 ohm Smith Chart.

So far so good.

73

Arie PA3A


Op 8-8-2022 om 03:40 schreef John Gord via groups.io:

Gerard,
It looks like the latest H and H4 firmware from DiSlord also has the Port-Z rescaling.
--John Gord

On Sun, Aug 7, 2022 at 11:34 AM, John Gord wrote:


Re: How find crystal filter terminaison resistor and capacitor

 

Gerard,
It looks like the latest H and H4 firmware from DiSlord also has the Port-Z rescaling.
--John Gord

On Sun, Aug 7, 2022 at 11:34 AM, John Gord wrote:


Gerard,
In addition to the variable resistance fixture method, there is provision in
some firmware versions to mathematically modify the displayed data to show
what the response would be in a system with Z0 other than 50 ohms.
I think that this feature is available only for the V2 and later versions
because of the memory limitations in the original NanoVNA.
You can set Z0 to say, 330 ohms for typical 10.7 MHz ceramic filters. I don't
know how well this would work at 4kohm.
The DiSlord firmware has the Port-Z setting in the DISPLAY menu. The
ojisankoubou firmware has the Port-Z setting in the DISPLAY/SIMULATE menu.
--John Gord

On Sun, Aug 7, 2022 at 03:04 AM, Gerard wrote:


Hello,
I have a lot of 2 poles filters 20J26 Motorola and 45R15AZ.
I can¡¯t find the datasheet of these filters on the net, except on a site
that tells me that the 45R15AZ is a 3rd harmonic filter, but no datasheet.
So I have no value of termination resistance and capacity.
In addition, if you take a common model like a 45M15A, you find different
values depending on the manufacturer, it ranges from 560 Ohm/1pf to 4KOhm
-1pf.
My question is whether we can measure these values with a nanovna or some
other method.
and if you have the datasheet, put it.
Thank you


Re: How find crystal filter terminaison resistor and capacitor

 

Gerard,
In addition to the variable resistance fixture method, there is provision in some firmware versions to mathematically modify the displayed data to show what the response would be in a system with Z0 other than 50 ohms.
I think that this feature is available only for the V2 and later versions because of the memory limitations in the original NanoVNA.
You can set Z0 to say, 330 ohms for typical 10.7 MHz ceramic filters. I don't know how well this would work at 4kohm.
The DiSlord firmware has the Port-Z setting in the DISPLAY menu. The ojisankoubou firmware has the Port-Z setting in the DISPLAY/SIMULATE menu.
--John Gord

On Sun, Aug 7, 2022 at 03:04 AM, Gerard wrote:


Hello,
I have a lot of 2 poles filters 20J26 Motorola and 45R15AZ.
I can¡¯t find the datasheet of these filters on the net, except on a site
that tells me that the 45R15AZ is a 3rd harmonic filter, but no datasheet.
So I have no value of termination resistance and capacity.
In addition, if you take a common model like a 45M15A, you find different
values depending on the manufacturer, it ranges from 560 Ohm/1pf to 4KOhm
-1pf.
My question is whether we can measure these values with a nanovna or some
other method.
and if you have the datasheet, put it.
Thank you


Re: Smith's book. free download

 

You can create your own by printing or phocopying a blank chart onto A4 transparency film.- Michael (GW7BBY)

On 06/08/2022 21:46, alan victor wrote:
That book text site has a GOLDMINE of super books. Thanks for the link!

The Smith applications text comes with a dozen or so plastic overlays that are used in the text as a means of solving designs. You use a grease pencil.
Almost as munch fun as fooling with the vna. I have the originals and some where I stored away some clear plastic copies that I used in analog powerpoint
presentations!

Alan




Re: Smith's book. free download

 

Interesting! I use PCmatic anti-virus and it's perfectly happy with that site?? Rudy N6LF


Re: Smith's book. free download

 

Oops, 27 MB!

73,

Justin B.
KI5GKD


Re: Smith's book. free download

 

TNX, just downloaded it. Pretty hefty PDF @ 21 MB!

Not sure I'll understand anything in it... :-\

73,

Justin B.
KI5GKD


Re: Smith's book. free download

 

There are (were?) available plastic Smith charts with a rotatable outer scale and a slide-rule-like cursor, both pivoting on a rivet dead center on the chart. The cursor saved a lot of grease pencil plotting.
My copy of the book included erasable markers colored to match the various chart grids, to easier keep track of whether you were plotting impedances or admittances.
73, Don N2VGU


Re: How find crystal filter terminaison resistor and capacitor

 

People seem to do it with variable resistors at input and output and tweak those untill the passband looks nice and flat.
Then the resistors can be measured with a multimeter to find out the impedance.


How find crystal filter terminaison resistor and capacitor

 

Hello,
I have a lot of 2 poles filters 20J26 Motorola and 45R15AZ.
I can¡¯t find the datasheet of these filters on the net, except on a site that tells me that the 45R15AZ is a 3rd harmonic filter, but no datasheet.
So I have no value of termination resistance and capacity.
In addition, if you take a common model like a 45M15A, you find different values depending on the manufacturer, it ranges from 560 Ohm/1pf to 4KOhm -1pf.
My question is whether we can measure these values with a nanovna or some other method.
and if you have the datasheet, put it.
Thank you


Re: Smith's book. free download

 

Thank you! My browser wouldn't let me get it by clicking on the download button. But I was able to open it in pdf and then download.

Al, K2WM

On 8/6/2022 12:52 PM, rseverns@... wrote:
You can get a free copy of the second edition here:

Rudy N6LF




Re: Smith's book. free download

 

That book text site has a GOLDMINE of super books. Thanks for the link!

The Smith applications text comes with a dozen or so plastic overlays that are used in the text as a means of solving designs. You use a grease pencil.
Almost as munch fun as fooling with the vna. I have the originals and some where I stored away some clear plastic copies that I used in analog powerpoint
presentations!

Alan


Re: Smith's book. free download

 

My Malwarebytes firewall blocked the above link, and claimed it was due to a Trojan; false positive perhaps???IMHO, With regard to the file size differences of the previous two links to copies. One copy of the book appears to?have been from a book which had been essentially scanned in page by page to create a pdf file. (The pages almost look?like a photocopy). The newer book appears to be a textualized copy of the original book converted to a pdf file.

On Saturday, August 6, 2022 at 12:53:00 PM EDT, <rseverns@...> wrote:

You can get a free copy of the second edition here:

Rudy N6LF


Re: Smith's book. free download

 

You can get a free copy of the second edition here:

Rudy N6LF


Re: Smith's book. free download

 

On 06/08/2022 17:14, Roy J. Tellason, Sr. wrote:
Hm, 27MB as opposed to the 18.6MB from the link that I just posted, and the two sites appear to be*very* similar, if not identical. I wonder what the differences are in the files?
Different editions of the book.

David
--
SatSignal Software - Quality software for you
Web:
Email: david-taylor@...
Twitter: @gm8arv


Re: Smith's book. free download

 

On Friday 05 August 2022 04:38:10 pm Larry McElhiney via groups.io wrote:
Free PDF download here:



Just downloaded it.

Larry
AC9OX
Hm, 27MB as opposed to the 18.6MB from the link that I just posted, and the two sites appear to be *very* similar, if not identical. I wonder what the differences are in the files?

--
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


Re: Smith's book. free download

 

On Friday 05 August 2022 03:34:22 pm Jim Lux wrote:
"Electronic applications of the Smith Chart
in waveguide, circuit and component analysis"
Phillip H Smith
This it?




--
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


Re: NanaVNA H4 battery indicator shows full but unit powers off after a minute

 

If you look at a graph of voltage versus discharge time, you will see a knee where the voltage drops quickly just before the battery is fully depleted. If you want to test battery performance read my article QST May 2022 page 34.

Charge the battery and retry.. My battery lasts in excess of 45 minutes.

If you want to know more about batteries I recommend



Larry W8LM


Re: Smith's book. free download

 

In many cases, a PDF copy of a book is as good, or maybe better, than a hard copy. In
the case of Phillip Smith's book, I would urge you to obtain a hard copy of the book,
if the opportunity occurs, even if you have a PDF copy.

An envelope on the inside back cover of the book contains four transparencies
(overlay charts) that are designed to be written on with a pencil and then erased for
further use:

Chart A - Standard SMITH CHART with normalized series-impedance or shunt-
admittance coordinates.

Chart B - SMITH CHART with normalized parallel-impedance or series-admittance
coordinates.

Chart C - SMITH CHART with normalized negative series-resistance or shunt-
conductance coordinate components.

Chart D - CARTER CHART with polar-impedance coordinates.

73,

Maynard
W6PAP

On Saturday, August 06, 2022 01:10:14 AM Chris Gardner via groups.io wrote:
Bryan, Thank you much for providing the opportunity to access this
magnificent publication. 73 kd2wot / Chris On Friday, August 5, 2022 at
08:39:40 PM EDT, Bryan Steinberg <bryan@...> wrote:

Here's a link to the document:

eguide-circuit-and-component-analysis-1snrusdcv2h8

73, Bryan, KB?A





Re: Smith's book. free download

 

Bryan has provided the link to the updated 2nd edition that was published in 2000 by SciTech Publishing, Inc.

73 - Dino KL?S