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No, what you want is a coupler. A coax jumper will throw the X and R values off some which would defeat the purpose of measuring at the antenna itself. If measuring at the antennas feed point you want as little as possible between the analyzer and the antenna, which is a male to male coupler. If you can get that coax jumper under a foot in length it will be very close, however, if you have direct access to the antenna's feed point it is easier and cheaper to just buy a coupler...

Something like this.

And just a note on what Road Squawker said, SWR (or VSWR for one of the long forms) doesn't change with coax length as stated in the manual he quoted. I am clarifying this as he essentially said two very different things in his post. What repeats is the R and X readings, and they repeat every electrical half wavelength, not physical half wavelength, which is why you need to factor in the velocity factor, and why the coax used will be be physically shorter than a physical half wavelength.

The DB

<blockquote data-quote="The DB" data-source="post: 540910" data-attributes="member: 21346">No, what you want is a coupler.&nbsp; A coax jumper will throw the X and R values off some which would defeat the purpose of measuring at the antenna itself.&nbsp; If measuring at the antennas feed point you want as little as possible between the analyzer and the antenna, which is a male to male coupler.&nbsp; If you can get that coax jumper under a foot in length it will be very close, however, if you have direct access to the antenna&#039;s feed point it is easier and cheaper to just buy a coupler...Something like <a href="http://www.mfjenterprises.com/Product.php?productid=MFJ-7702" target="_blank">this</a>.And just a note on what Road Squawker said, SWR (or VSWR for one of the long forms) doesn&#039;t change with coax length as stated in the manual he quoted.&nbsp; I am clarifying this as he essentially said two very different things in his post.&nbsp; What repeats is the R and X readings, and they repeat every electrical half wavelength, not physical half wavelength, which is why you need to factor in the velocity factor, and why the coax used will be be physically shorter than a physical half wavelength.<a href="http://hittman.us" target="_blank">The DB</a></blockquote>

[QUOTE="The DB, post: 540910, member: 21346"] No, what you want is a coupler. A coax jumper will throw the X and R values off some which would defeat the purpose of measuring at the antenna itself. If measuring at the antennas feed point you want as little as possible between the analyzer and the antenna, which is a male to male coupler. If you can get that coax jumper under a foot in length it will be very close, however, if you have direct access to the antenna's feed point it is easier and cheaper to just buy a coupler... Something like [URL='http://www.mfjenterprises.com/Product.php?productid=MFJ-7702'][COLOR=#0080ff]this[/COLOR][/URL]. And just a note on what Road Squawker said, SWR (or VSWR for one of the long forms) doesn't change with coax length as stated in the manual he quoted. I am clarifying this as he essentially said two very different things in his post. What repeats is the R and X readings, and they repeat every electrical half wavelength, not physical half wavelength, which is why you need to factor in the velocity factor, and why the coax used will be be physically shorter than a physical half wavelength. [URL='http://hittman.us'][COLOR=#000000]The DB[/COLOR][/URL] [/QUOTE]

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