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-   -   MFJ Antennae analysers? VNWA? (https://www.radiobanter.com/equipment/223327-mfj-antennae-analysers-vnwa.html)

[email protected] December 26th 15 11:25 PM

MFJ Antennae analysers? VNWA?
 
In rec.radio.amateur.antenna Jim GM4DHJ ... wrote:
On 26/12/2015 22:41, wrote:
In rec.radio.amateur.antenna Jim GM4DHJ ... wrote:

wrote in message
...
In rec.radio.amateur.antenna Ralph Mowery
wrote:

wrote in message
...
Despite its high price and snazzy interface, does it provide any more
useful information then the tried-and-trusted (transistorised!) GDO?

That depends on whether or not you have the skills to utilize the
information such devices provide.


Most of the hams I have seen with the MFJ do not have the skills to
really
use it and a simple swr meter would do just as well or beter for them.

That's a sad comment and contrary to my experience, though most of the
hams I know are also engineers or technicians in real life.

professionals should take up another hobby ......


Why?



because they are a pain in the arse trying to lord it over
non-professionals trying to enjoy their hobby ...


You mean like when they disparage old wives tales that have been passed
down from the days of spark but contradict the laws of physics?



--
Jim Pennino

Jeff Liebermann[_2_] December 27th 15 04:13 AM

MFJ Antennae analysers? VNWA?
 
On Sat, 26 Dec 2015 12:24:54 -0000, "gareth"
wrote:

Anyone have an inkling of what you get for your £350-odd?


You can probably get a fair idea of what's inside and how it works
from the following links. The major limitations of the MFJ-259/269
analyzers is the inability to sweep a frequency range and the tendency
for static electricity or too much RF to blow out the front end
diodes.

MFJ-269 repair:
http://802.11junk.com/jeffl/MFJ-269-repair/

MFJ-269 schematic:
http://802.11junk.com/jeffl/MFJ-269-repair/mfj-269-schematic.pdf

MFJ-259 calibration:
http://www.w8ji.com/mfj-259b_calibration.htm
http://www.ok1cjb.cz/pdf/390_kalibrace.pdf

Build Your Own Antenna Analyzer for under $50
http://www.hamstack.com/project_antenna_analyzer.html
http://www.hamstack.com/hs_projects/k6bez_antenna_analyzer.pdf

For single port measurements, I prefer to use a return loss bridge:
https://www.google.com/search?q=return+loss+bridge&tbm=isch
http://www.qsl.net/n9zia/wireless/pics/rtrn_loss_bridge.png
It doesn't give reactance information or draw a Smith Chart as with a
real VNA. It also requires an RF sweep generator and an oscilloscope.
With a collection of small bridges, I can sweep and measure most
anything from VLF to wi-fi:
http://pe2er.nl/wifiswr/

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

Jim GM4DHJ ...[_2_] December 27th 15 06:21 AM

MFJ Antennae analysers? VNWA?
 
On 26/12/2015 23:25, wrote:
In rec.radio.amateur.antenna Jim GM4DHJ ... wrote:
On 26/12/2015 22:41,
wrote:
In rec.radio.amateur.antenna Jim GM4DHJ ... wrote:

wrote in message
...
In rec.radio.amateur.antenna Ralph Mowery
wrote:

wrote in message
...
Despite its high price and snazzy interface, does it provide any more
useful information then the tried-and-trusted (transistorised!) GDO?

That depends on whether or not you have the skills to utilize the
information such devices provide.


Most of the hams I have seen with the MFJ do not have the skills to
really
use it and a simple swr meter would do just as well or beter for them.

That's a sad comment and contrary to my experience, though most of the
hams I know are also engineers or technicians in real life.

professionals should take up another hobby ......

Why?



because they are a pain in the arse trying to lord it over
non-professionals trying to enjoy their hobby ...


You mean like when they disparage old wives tales that have been passed
down from the days of spark but contradict the laws of physics?



yes...and boy do they love to make you feel small....

--
Moderated groups kill abuse
No spare wheel isn't progress
The latest model is not always the best
A rubber cam belt is not acceptable
Cheat your way through life, join the Freemasons
DIGITAL just doesn't work

Brian Reay[_5_] December 27th 15 09:46 AM

MFJ Antennae analysers? VNWA?
 
On 27/12/15 06:21, Jim GM4DHJ ... wrote:
On 26/12/2015 23:25, wrote:
In rec.radio.amateur.antenna Jim GM4DHJ ...
wrote:
On 26/12/2015 22:41,
wrote:
In rec.radio.amateur.antenna Jim GM4DHJ ...
wrote:

wrote in message
...
In rec.radio.amateur.antenna Ralph Mowery

wrote:

wrote in message
...
Despite its high price and snazzy interface, does it provide
any more
useful information then the tried-and-trusted (transistorised!)
GDO?

That depends on whether or not you have the skills to utilize the
information such devices provide.


Most of the hams I have seen with the MFJ do not have the skills to
really
use it and a simple swr meter would do just as well or beter for
them.

That's a sad comment and contrary to my experience, though most of
the
hams I know are also engineers or technicians in real life.

professionals should take up another hobby ......

Why?



because they are a pain in the arse trying to lord it over
non-professionals trying to enjoy their hobby ...


You mean like when they disparage old wives tales that have been passed
down from the days of spark but contradict the laws of physics?



yes...and boy do they love to make you feel small....



You are simply blaming others for your own lack of knowledge, hardwork,
and self-esteem. Take some responsibility for your life.



--
Why you should not ignore animal neglect and cruelty:
http://www.caar-uk.org/why.html

Jim GM4DHJ ...[_2_] December 27th 15 11:37 AM

MFJ Antennae analysers? VNWA?
 

"Brian Reay" wrote in message
...
On 27/12/15 06:21, Jim GM4DHJ ... wrote:
On 26/12/2015 23:25, wrote:
In rec.radio.amateur.antenna Jim GM4DHJ ...
wrote:
On 26/12/2015 22:41,
wrote:
In rec.radio.amateur.antenna Jim GM4DHJ ...
wrote:

wrote in message
...
In rec.radio.amateur.antenna Ralph Mowery

wrote:

wrote in message
...
Despite its high price and snazzy interface, does it provide
any more
useful information then the tried-and-trusted (transistorised!)
GDO?

That depends on whether or not you have the skills to utilize the
information such devices provide.


Most of the hams I have seen with the MFJ do not have the skills to
really
use it and a simple swr meter would do just as well or beter for
them.

That's a sad comment and contrary to my experience, though most of
the
hams I know are also engineers or technicians in real life.

professionals should take up another hobby ......

Why?



because they are a pain in the arse trying to lord it over
non-professionals trying to enjoy their hobby ...

You mean like when they disparage old wives tales that have been passed
down from the days of spark but contradict the laws of physics?



yes...and boy do they love to make you feel small....



You are simply blaming others for your own lack of knowledge, hardwork,
and self-esteem. Take some responsibility for your life.



........political and contentious sig deleted .....

No I blame others for being conceited and big headed ......thank god for the
moderated group where you can get a reply to a technical query without the
snide comments ...



gareth December 27th 15 12:15 PM

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.



[email protected] December 27th 15 06:45 PM

MFJ Antennae analysers? VNWA?
 
In rec.radio.amateur.antenna Jim GM4DHJ ... wrote:
On 26/12/2015 23:25, wrote:
In rec.radio.amateur.antenna Jim GM4DHJ ... wrote:
On 26/12/2015 22:41,
wrote:
In rec.radio.amateur.antenna Jim GM4DHJ ... wrote:

wrote in message
...
In rec.radio.amateur.antenna Ralph Mowery
wrote:

wrote in message
...
Despite its high price and snazzy interface, does it provide any more
useful information then the tried-and-trusted (transistorised!) GDO?

That depends on whether or not you have the skills to utilize the
information such devices provide.


Most of the hams I have seen with the MFJ do not have the skills to
really
use it and a simple swr meter would do just as well or beter for them.

That's a sad comment and contrary to my experience, though most of the
hams I know are also engineers or technicians in real life.

professionals should take up another hobby ......

Why?



because they are a pain in the arse trying to lord it over
non-professionals trying to enjoy their hobby ...


You mean like when they disparage old wives tales that have been passed
down from the days of spark but contradict the laws of physics?



yes...and boy do they love to make you feel small....


Sounds like sour grapes to me.

Most hams I know are eager to learn new things.


--
Jim Pennino

[email protected] December 27th 15 06:46 PM

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

Jeff Liebermann[_2_] December 27th 15 07:50 PM

MFJ Antennae analysers? VNWA?
 
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




--
Jeff Liebermann

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

Fred Roberts December 27th 15 07:55 PM

MFJ Antennae analysers? VNWA?
 
On 27/12/2015 18:45, wrote:

yes...and boy do they love to make you feel small....


Sounds like sour grapes to me.

Most hams I know are eager to learn new things.


Morse is pretty new to some "hams" around here.



--
Extend ****s law - make 'em wear a cheat sheet 24/7


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