Re: Antennas
Slide rules: https://www.oughtred.org/index.shtml Larry AC9OX
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Larry McElhiney
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#29046
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Re: Antennas
I have two different Post slide rules from back in the day, but my most valued one is specifically designed for electronics formula use by Picket (reactance, resonance, resistance, etc). Stephen W9SK
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Stephen W9SK
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#29045
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Re: Antennas
One must wonder if you ever owned a slide rule? hihi (Still own my eye saving yellow one by Picket) I recently saw an article for a 20 Meter beam with dimensions in 1/10,000ths of an inch. Someone
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KENT BRITAIN
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#29044
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Re: cut/lengthen vertical antenna wire
And forgets to say whether these are Imperial Gallons (defined as 4.54609l) or Queen Anne (as used in the USA) gallons (defined as 231 cubic inches¡ªwhatever an inch might have been at the time,
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G8DQX list
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#29043
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Re: nanovna-saver question
#nanovna-saver
Thanks Roger. Using Linux Mint here. Found the file though ~/.config/NanoVNASaver/NanoVNASaver.ini But there don't appear to be any sweep settings in that file except
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Nick
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#29042
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Re: Touchstone file format
#consolecommands
#docs
While the file format spec may define formats for things other than S parameters, they're not particularly common. Not to say that they don't exist, but every tool I've used only uses S parameters. Th
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Jim Lux
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#29041
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Re: cut/lengthen vertical antenna wire
Hey guys, Bringing the? reactance to zero (if you really want that for your antenna), don't forget that there might be a coax cable involved in the measurement set-up.? That coax can move the Z of
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Arie Kleingeld PA3A
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#29040
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Re: cut/lengthen vertical antenna wire
I agree with W0LEV 100% on using the phase information to guide one's tuning efforts. That valuable phase information is what puts the "Vector" in "vector network analyzer"(VNA) and is what makes it
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Donald S Brant Jr
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#29039
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Re: Touchstone file format
#consolecommands
#docs
Sorry, checked the wrong input file, scikit-rf cannot read Z-Parameter (NotImplementedError: only s-parameters supported for now.): Traceback (most recent call last): File "<stdin>", line 1, in
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Ho-Ro
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#29038
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Re: Touchstone file format
#consolecommands
#docs
Did you see the example 9 and 10 from my posting below (out of touchstone rev 2.0 spec)? You can for sure store also impedance in a s1p file if you calculate the Z-parameter from S-parameter - this is
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Ho-Ro
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#29037
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Re: cut/lengthen vertical antenna wire
Hey Doug, If you can figure out how to build and tune an antenna with the Nano after a stroke you¡¯re OK in my book (a retired family doc). The body may not follow all your commands but some of the
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David Wilcox K8WPE
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#29036
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Re: Touchstone file format
#consolecommands
#docs
In a .S1P file it is not an impedance that is described but S11 # HZ S RI R 50 6800000 0.4178235144152254 -0.6694732263322638 For each line you find in order: Frequency in Hz the real part of S11 the
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F1AMM <18471@...>
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#29035
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Re: Read polar impedance (Ohms and phase) directly?
I attach simple Excel file for the same example. It uses some of the in-built functions for dealing with complex numbers. A complete list of available functions can be found at
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Ed G8FAX
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#29034
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Touchstone file format
#consolecommands
#docs
Hi, https://github.com/Ho-Ro/nanovna-tools When developing my nanovna mini-tools, I am unclear about the "Touchstone" file format regarding the storage of Z-parameters for a one-port (nanovna_snp.py).
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Ho-Ro
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#29033
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Re: Common ground and 2-port measuring
Thanks Ed, AG6CX, An interesting read. Kind regards Ed, G8FAX
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Ed G8FAX
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#29032
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Re: Read polar impedance (Ohms and phase) directly?
Hi Francois, Here is a worked example in a simple way avoiding manipulations with the complex conjugate. Based on the example at bottom of page 3 of the document. I will start off with Zn = 2.33 +
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Ed G8FAX
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#29031
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Re: Read polar impedance (Ohms and phase) directly?
I had already browsed this website I did not find the text relevant and, as a result, I did not trust what I was reading there. It lacks, as often, many developments to understand. Example : Back to
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F1AMM <18471@...>
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#29030
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Re: cut/lengthen vertical antenna wire
Hi Doug The 234/freq is a average, not an exact value. The real value varies with the diameter of the wire element. Much like the lad who puts 7 gal of petrol in his car, drives 243 miles,and says he
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KENT BRITAIN
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#29029
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Re: cut/lengthen vertical antenna wire
What's a lot of fun is to make a ground plane antenna, and then hook up a VNA, and watch how it changes as you bend things. People spend a lot of time trying to build matching networks, when often,
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Jim Lux
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#29028
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Re: Common ground and 2-port measuring
To those interested in Woodward's work, I found the 1953 paper that was referenced in the recent link. Sent FYI. Ed McCann AG6CX Sausalito
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AG6CX
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#29027
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