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what is your vswr at the antenna?

Eldorado828

8-2-8 in the Lonestar state
Feb 21, 2016
2,867
5,192
523
The Lonestar State
Ok, so going into some antenna experiments at the house and going to out the rigexpert to work.

I hear you seasoned techs talking about swr at the feed point of the antenna.

If using per se rg8x as the jumper to that feed point, how long a jumper should a guy use?
 

Crawdad

Down in the mud invasive species
Nov 11, 2016
902
1,884
153
I believe it's dependent on your frequency of operation. A half wavelength times the velocity factor of your 8x. The real experts will be along to correct me I hope.
 

The DB

Sr. Member
Aug 14, 2011
2,008
1,536
193
St. Louis, MO
Ok, so going into some antenna experiments at the house and going to out the rigexpert to work.

I hear you seasoned techs talking about swr at the feed point of the antenna.

If using per se rg8x as the jumper to that feed point, how long a jumper should a guy use?

The first question is, what version RigExpert do you have. The AA-55 Zoom and up you don't need to worry about coax length as it is possible to calibrate out the effects of the coax, there are instructions for this in the manual, look in the table of contents for the word "Calibration". If, however, you have the AA-35 Zoom, unfortunately there is no way to do this.

If you look at the AA-35 Zoom manual, on page 17, there are instructions on making a half wavelength coax for a specific frequency. A word of note, this half wavelength coax is good for exactly one frequency and one frequency only. It does not cover the entire range of the graphs that the device displays, or even the CB band. The further you get away from its tuned frequency, the less accurate it will be.

Honestly, because of this limitation, I highly recommend staying away from the RigExpert AA-35 Zoom, and getting the next version up. Yea, its about $50 more, but take it from someone who has worked with multiple devices over the years from the very cheap to the very expensive, the ability to calibrate out the effects of the feed line is worth much more than this small difference in price. Yes, it adds an extra step, but at the same time it also gets you much more accurate results that you can rely on.


The DB
 

Eldorado828

8-2-8 in the Lonestar state
Feb 21, 2016
2,867
5,192
523
The Lonestar State
The first question is, what version RigExpert do you have. The AA-55 Zoom and up you don't need to worry about coax length as it is possible to calibrate out the effects of the coax, there are instructions for this in the manual, look in the table of contents for the word "Calibration". If, however, you have the AA-35 Zoom, unfortunately there is no way to do this.

If you look at the AA-35 Zoom manual, on page 17, there are instructions on making a half wavelength coax for a specific frequency. A word of note, this half wavelength coax is good for exactly one frequency and one frequency only. It does not cover the entire range of the graphs that the device displays, or even the CB band. The further you get away from its tuned frequency, the less accurate it will be.

Honestly, because of this limitation, I highly recommend staying away from the RigExpert AA-35 Zoom, and getting the next version up. Yea, its about $50 more, but take it from someone who has worked with multiple devices over the years from the very cheap to the very expensive, the ability to calibrate out the effects of the feed line is worth much more than this small difference in price. Yes, it adds an extra step, but at the same time it also gets you much more accurate results that you can rely on.


The DB
Thank you for the reply.
I have the aa-54 (not the zoom) and it appears to be as you're stating with this older model too.
So now I'll do some more reading and determine what I'll need.

Your help is greatly appreciated sir.
 

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