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Old December 27th 15, 12:15 PM posted to uk.radio.amateur,rec.radio.amateur.equipment,rec.radio.amateur.antenna
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Default MFJ Antennae analysers? VNWA?

"gareth" wrote in message
...

These questions are raised by the possibility of resurrecting a project
with
a former colleague from uni 43 years ago, now that we are both retired,
although it will be dismissed cynically as vapourware by some nasty
individual,
to produce a speccy covering up to 10GHz together with tracking genny
but based aroind COTS components that feature more and more
in domestic white goods.



There are two aspects of vector analysis under consideratiom; the first,
as for antennae measurement is to assess the amplitude and phase of
reflected
power from various circuits, which is where the interest in the VNWA arises,
but the second is the analysis of complex modulation, particularly
where there are constellations.


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Old December 27th 15, 06:46 PM posted to uk.radio.amateur,rec.radio.amateur.equipment,rec.radio.amateur.antenna
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Default MFJ Antennae analysers? VNWA?

In rec.radio.amateur.antenna gareth wrote:
"gareth" wrote in message
...

These questions are raised by the possibility of resurrecting a project
with
a former colleague from uni 43 years ago, now that we are both retired,
although it will be dismissed cynically as vapourware by some nasty
individual,
to produce a speccy covering up to 10GHz together with tracking genny
but based aroind COTS components that feature more and more
in domestic white goods.



There are two aspects of vector analysis under consideratiom; the first,
as for antennae measurement is to assess the amplitude and phase of
reflected
power from various circuits, which is where the interest in the VNWA arises,
but the second is the analysis of complex modulation, particularly
where there are constellations.


I can not think of any antenna that modulates signals.


--
Jim Pennino
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Old December 27th 15, 08:33 PM posted to uk.radio.amateur,rec.radio.amateur.equipment,rec.radio.amateur.antenna
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Default MFJ Antennae analysers? VNWA?

On Sun, 27 Dec 2015 20:15:10 -0000, wrote:

In rec.radio.amateur.antenna Jeff Liebermann wrote:
On Sun, 27 Dec 2015 18:46:42 -0000,
wrote:

I can not think of any antenna that modulates signals.


I talk to my antennas all the time. I only worry when they talk back.

DAM (Direct Antenna Modulation):
http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=5464640&url=http%3A%2F%2Fie eexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber% 3D5464640
http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=1339221&url=http%3A%2F%2Fie eexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber% 3D1339221
https://www.google.com/search?q=direct+antenna+modulation


Got plans for one for 40 meters?


Of course not. I just wanted to point out that there is such a thing
as an antenna modulator.

Skimming the literature, it seems to be made for very wide band mm
wave communications, not HF. I also don't have much of a clue as to
how it works. I think the ham radio version will need to wait until
the military and governments are done with their testing.



--
Jeff Liebermann

150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558


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Old December 27th 15, 08:01 PM posted to uk.radio.amateur,rec.radio.amateur.equipment,rec.radio.amateur.antenna
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Default MFJ Antennae analysers? VNWA?

On Sun, 27 Dec 2015 12:15:51 -0000, "gareth"
wrote:

There are two aspects of vector analysis under consideratiom; the first,
as for antennae measurement is to assess the amplitude and phase of
reflected
power from various circuits, which is where the interest in the VNWA arises,
but the second is the analysis of complex modulation, particularly
where there are constellations.


Antenna analyzers do NOT demodulate signals or present constellation
plots. They only measure antenna and transmission line impedances.
For a constellation plot, you'll need a service monitor with the
decoding software for whatever modulation type you want to view.
Compared to an MFJ-259/269, that will increase your test equipment
budget about 500 times. Or you can search for an RTL-SDR
implimentation that displays a constellation plot. Maybe this one:
http://yo3iiu.ro/blog/?p=1393
Lots of jitter, but cheap.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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Old December 28th 15, 07:57 AM posted to uk.radio.amateur,rec.radio.amateur.equipment,rec.radio.amateur.antenna
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Default MFJ Antennae analysers? VNWA?

professionla bounce up with snide comments ......


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Old December 28th 15, 07:33 PM posted to uk.radio.amateur,rec.radio.amateur.equipment,rec.radio.amateur.antenna
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Default MFJ Antennae analysers? VNWA?

On Mon, 28 Dec 2015 07:57:37 -0000, "Jim GM4DHJ ..."
wrote:

professionla bounce up with snide comments ......


Nothing of value has ever been written on one line.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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Old December 28th 15, 07:35 PM posted to uk.radio.amateur,rec.radio.amateur.equipment,rec.radio.amateur.antenna
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Default MFJ Antennae analysers? VNWA?

Jeff Liebermann wrote:
On Mon, 28 Dec 2015 07:57:37 -0000, "Jim GM4DHJ ..."
wrote:

professionla bounce up with snide comments ......


Nothing of value has ever been written on one line.


A bird in the hand is always greener on the other side.

--
STC // M0TEY // twitter.com/ukradioamateur
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Old December 28th 15, 07:43 PM posted to uk.radio.amateur,rec.radio.amateur.equipment,rec.radio.amateur.antenna
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Default MFJ Antennae analysers? VNWA?


"Jeff Liebermann" wrote in message
...
On Mon, 28 Dec 2015 07:57:37 -0000, "Jim GM4DHJ ..."
wrote:

professionla bounce up with snide comments ......


Nothing of value has ever been written on one line.

Jeff Liebermann


very true... I spelt that the wrong way....




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