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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 |
MFJ Antennae analysers? VNWA?
In rec.radio.amateur.antenna Fred Roberts wrote:
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. You do know that there has been a resurgence in interest in morse code since the US eliminated it as a requirement? -- Jim Pennino |
MFJ Antennae analysers? VNWA?
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? -- Jim Pennino |
MFJ Antennae analysers? VNWA?
wrote in message ... 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 you mean fuel guru status? ... |
MFJ Antennae analysers? VNWA?
"Fred Roberts" wrote in message ... 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. yes they should learn something not connected with their profession..... |
MFJ Antennae analysers? VNWA?
professionla bounce up with snide comments ......
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MFJ Antennae analysers? VNWA?
wrote:
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. Most hams that post to uk.radio.amateur are incapable of learning new things. -- STC // M0TEY // twitter.com/ukradioamateur |
MFJ Antennae analysers? VNWA?
"Stephen Thomas Cole" wrote in message ... wrote: 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. Most hams that post to uk.radio.amateur are incapable of learning new things. yes brian never did learn CW .... |
MFJ Antennae analysers? VNWA?
On 27/12/2015 20:33, Jeff Liebermann wrote:
Of course not. I just wanted to point out that there is such a thing as an antenna modulator. I can think of one - the wind. A friend uses a VHF vertical. In very strong winds, his signal is amplitude modulated as the thing gets bent right over! Les. |
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