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
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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
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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
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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
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Re: Smith's book. free download
The title of the book is "Electronic Applications Of The Smith Chart"
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Re: Smith's book. free download
On 8/5/22 5:14 PM, Donald Hellen wrote: Is this the book?
You have to go through the process on that website, then let it compress the book before you download it. I have no idea if it's in the public domain at this point or not, or if copyright still applies, so download at your own risk. I clicked the first download button and not the download original button.
The book is still sold as an e-book:
If it is out of copyright protection, it wouldn't be the first time a book in the public domain was for sale.
Donald KX8K
It was published after 1927, so most likely, it is still under copyright.
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Re: Smith's book. free download
Bryan, Thank you much for providing the opportunity to access this magnificent publication.?73 kd2wot / Chris
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On Friday, August 5, 2022 at 08:39:40 PM EDT, Bryan Steinberg <bryan@...> wrote:
Here's a link to the document:
73, Bryan, KB?A
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My copy has 253 pages. My guess is that that is the real thing.
Chuck KF8TI
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On Aug 5, 2022, at 8:14 PM, Donald Hellen <donhellen@...> wrote:
Is this the book?
You have to go through the process on that website, then let it compress the book before you download it. I have no idea if it's in the public domain at this point or not, or if copyright still applies, so download at your own risk. I clicked the first download button and not the download original button.
The book is still sold as an e-book:
If it is out of copyright protection, it wouldn't be the first time a book in the public domain was for sale.
Donald KX8K
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Re: Smith's book. free download
Here's a link to the document:
73, Bryan, KB?A
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Re: Smith's book. free download
Is this the book?
You have to go through the process on that website, then let it compress the book before you download it. I have no idea if it's in the public domain at this point or not, or if copyright still applies, so download at your own risk. I clicked the first download button and not the download original button.
The book is still sold as an e-book:
If it is out of copyright protection, it wouldn't be the first time a book in the public domain was for sale.
Donald KX8K
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Re: At which point do we take the value of impedance to tune an antenna?
On Fri, Aug 5, 2022 at 09:49 AM, MICHAEL BELL wrote:
Roger, you make an excellent point. I would however like to point out that I
believe your 100 +j0 and 25 +j0 are swapped. 25 should be on the left side
and 100 should be on the right side of the graph. Am I wrong? Still trying to
learn Smith Charts.
73 Mike N7ATC
Mike, You are correct. I made an updated post yesterday. Unfortunately the group owner has disabled post editing so I was unable to change the original post. /g/nanovna-users/message/29143Roger
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Re: New owner of nanovna-H and H4, However pondering the next step in precision
for what you pay all the nano vna vna2 (and clones brothers sisters) are superb ...
he asked for a higher price range (but not 20k bucks)
something better as the v2 ... but not toooo expensive
and there the kc901 begins to shine .... much higher dynamic and accuracy but still portable .. more functions .. etc etc
not a used boatanchor with questionable results but new ... and exactly in his price range
climb a tower with a hp?? no way! ... do the same with a 901?? yes that does work well :-)
dg9bfc sigi
Am 04.08.2022 um 18:37 schrieb W0LEV:
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Don't downplay the accuracy of the NANOVNAs. I have compared several
offerings from the NANOVNAs with the HP 8753C with the associated
S-Parameter test set using HP cal. standards. The agreement, within each
other's limitations, is astounding. Sure, the cal. standards that come
with the NANOs are not the quality of those from HP, but not bad at all,
especially in the HF to low VHF range. I seriously doubt you will find
anything more "accurate" within your targeted price range. If you want to
increase your upper price limit to $10 or $12 killobucks, then, yes, you
can do better. You "might" find a used 8753C, but beware. I have a
friend who went that route for $4k, and the display does not behave
properly.
Dave - W?LEV
On Thu, Aug 4, 2022 at 4:30 AM Siegfried Jackstien <
siegfried.jackstien@...> wrote:
KC901
Different range (and so price) available
Between 1000 and 2000 bucks or so
Much more professional and accurate as all the Nanos... And still portable
use (with a bit bigger display)
So i recommend those if you really want to spent more for a better unit
Dg9bfc sigi
Am 04.08.2022 03:32 schrieb "0root via groups.io" <hntpro@...
:
Hi John
Good guess at both my range of interest(indeed below 900MHz) and the
education side... I have very limited techniques as im new to it all.
Im going to try and find that article you mention, if not il try to buy an
old hard copy of the mag on ebay.
Re the loads, you are referring to the three calibration connectors
provided correct?
Would making my own finer tuned ones be a realistic task? as in
components, pricing, and skill?
If not if you know anywhere to buy some finer tuned I would appreciate the
link
Thanks for the help!
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Re: New owner of nanovna-H and H4, However pondering the next step in precision
provided with the nanovna is not rpsma caps .. its an open .. a short and a load (not the best one but usable)
dg9bfc sigi
Am 04.08.2022 um 18:39 schrieb 0root via groups.io:
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Siegfried Jackstien - Thanks for the recommendation, I will research these.
John Gord - Re maintaining a consistent length between O, S, L - the three now provided with the nanoVNA are just RPSMA caps... therefore they should meet this criteria?
Thanks for the details on the article, Should be able to find it.
Donald S Brant Jr - Thanks for the recommendation, I'll research LibreVNA
Also, you're right re making your own...a matter of confidence vs doubt... I guess buying multiple kits then testing them all to see the alignment may help put faith in the chosen kit?
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Re: Smith's book. free download
thank you On Fri, Aug 5, 2022 at 1:38 PM Larry McElhiney via groups.io <lmcelhiney= [email protected]> wrote: Free PDF download here:
Just downloaded it.
Larry
AC9OX
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Re: NanaVNA H4 battery indicator shows full but unit powers off after a minute
Scott,
This may not help, but try leaving it charging overnight and see if that helps. It could be just the battery went bad.
73,
Cliff, AE5ZA
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On Aug 5, 2022, at 15:10, Scott Ginsburg <k1oa@...> wrote:
My battery indicator icon shows a full charge but the unit turns off after about a minute.
I charged it for about 5 minutes, unplugged the USB cable and it stayed on for about the same amount of time then turned off again, acting as if it needed a charge.
I have seen the indicator show a partial charge in the past.
I haven't used it in a few months, don't recall how much charge was on it when it was last used.
Is this a known issue?
tnx and 73,
Scott
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NanaVNA H4 battery indicator shows full but unit powers off after a minute
My battery indicator icon shows a full charge but the unit turns off after about a minute.
I charged it for about 5 minutes, unplugged the USB cable and it stayed on for about the same amount of time then turned off again, acting as if it needed a charge.
I have seen the indicator show a partial charge in the past.
I haven't used it in a few months, don't recall how much charge was on it when it was last used.
Is this a known issue?
tnx and 73,
Scott
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Re: Smith's book. free download
Here are the ISBN numbers for his book:
ISBN: 1-884932-39-8?
ISBN 13: 978-1-8849-3239-7
You may be able to find an electronic copy by searching the ISBN
numbers. ?I hope that helps.
Sincerely,
Everett McArthur
KE5QVC
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On Fri, 2022-08-05 at 19:39 +0000, W0LEV wrote: Thank's, Jim (Lux)!? I'm an old fart (75) and still much prefer a
printed
copy.?? With ARRL so non-technical these days, I seriously doubt we
could
convince them to, once again, carry the reprints?
At the time, $400 was all I had in my pocket in travel money from my
employer.? He knew what he had!!!? I'll never forget that meeting.? I
can
still review it in my mind's eyes......
Dave - W?LEV
On Fri, Aug 5, 2022 at 7:34 PM Jim Lux <jimlux@...> wrote:
On 8/5/22 11:38 AM, Charles Young wrote:
Smith Chart lovers:
A few months ago I downloaded a free copy of Mr. Smith¡¯s book. I
have
mislaid the URL. Keep looking. I am sure you will find it.
Chuck KF8TI
"Electronic applications of the Smith Chart
in waveguide, circuit and component analysis"
Phillip H Smith
It's not on archive.org
--
*Dave - W?LEV*
*Just Let Darwin Work*
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Re: upgrade old version NanoVNA H vers 3.4
Hi, I know the config DFU setting, but with my HW modification it is even faster to enter DFU mode - switch off, press the jog, switch on, release the jog - this helps me when I test my own FW modifications - and more important this works also when something goes wrong and the device doesn't respond anymore (luckily you cannot brick the NanoVNA, because the bootloader is built in HW and cannot be damaged).
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Re: Smith's book. free download
Free PDF download here:
Just downloaded it.
Larry
AC9OX
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Re: Smith's book. free download
On 8/5/22 12:39 PM, W0LEV wrote: Thank's, Jim (Lux)! I'm an old fart (75) and still much prefer a printed
copy. With ARRL so non-technical these days, I seriously doubt we could
convince them to, once again, carry the reprints? I'm not sure it would really be worth it - there are lots of later books which might have a better tutorial. So you'd be possessing it for its historical significance - for which the $400 might be reasonable. Amazon will sell you a copy for $90, hardcover, as an import from 1969. Abebooks will sell you various copies for more. They've got a first edition, fifth printing for $854 I used to use Bowick's RF Circuit Design which I see on Amazon is about $42 for the 2nd edition. Something like that might be a better choice for someone starting out.
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Re: Smith's book. free download
Thank's, Jim (Lux)! I'm an old fart (75) and still much prefer a printed
copy. With ARRL so non-technical these days, I seriously doubt we could
convince them to, once again, carry the reprints?
At the time, $400 was all I had in my pocket in travel money from my
employer. He knew what he had!!! I'll never forget that meeting. I can
still review it in my mind's eyes......
Dave - W?LEV
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On Fri, Aug 5, 2022 at 7:34 PM Jim Lux <jimlux@...> wrote: On 8/5/22 11:38 AM, Charles Young wrote:
Smith Chart lovers:
A few months ago I downloaded a free copy of Mr. Smith¡¯s book. I have
mislaid the URL. Keep looking. I am sure you will find it.
Chuck KF8TI
"Electronic applications of the Smith Chart
in waveguide, circuit and component analysis"
Phillip H Smith
It's not on archive.org
-- *Dave - W?LEV* *Just Let Darwin Work*
--
Dave - W?LEV
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Larry Macionski
Donald S Brant Jr
Roger Need
Martin Glazer
Ho-Ro
Larry McElhiney