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HF Rig....

You may need to play with jumper lengths to get the vswr down with the amp in line. What type readings do you get without amp Inline??
 
If you have your setup as described above, and you pull the amp out of line, what do the readings look like on the dosy?
 
When you say your mfj says 1.0 and 1.1 across the band. what are the X and R values at these readings? Is R near 50? Just curious.
 
the ohms with just the antenna is around 70ohms but i'll do some more testing with the jumpers, maybe i need to go to 3ft jumpers instead of 6ft...i take it 70ohms is bad!
 
ok took antenna to amp....and reading from mfj R=50 x=14 and right around 55 ohms, swr is 1.3...now gonna have all 3 inline and(OFF) and do a reading
 
Analyzers are great tools especially for building antennas and antenna matching. I use mine exclusively and couldn't do with out it since I now own one. If these were around when the old timers started out, I bet they would have appreciated back them as we do now.

Analyzers show you what your antenna system is doing and it is more than just a low SWR reading that makes an antenna resonant.

If you are interested in getting an analyzer, forget the MFJ 259b, they are antiquated. The RIG expert series are far better. It has more screens to select from with more information, and can plug into a computer via USB for more detailed graphs, and uses only 2 AA batteries where the MFJ use 10 batteries and drains them quick. It also can check 5 SWR readings at one time on user selectable bands which is nice for a quick check on multiband antennas.

http://www.rigexpert.com/index?s=aa54

Here is a screen shot from My RIGEXPERT analyzer on a previous post I put up analyzing a SIRIO performer 5000 mobile antenna.

img_20150316_140510-1-jpg.15414


As you can see this antenna at 26.580 MHz tested near perfect resonance at this frequency. The resistance value (R) matches the (Z) value which is the magnitude of impedance giving a reactance value of less than 0 resulting in a SWR of less than 1:1. It is also showing how much capacitance is in the circuit.

Here is a screen shot showing the SWR bandwidth of the antenna that the MFJ259B can't do. This also easily helps in finding the resonant point for adjusting the antenna by moving the curser arrow over to the lowest part of the curve which will change the analyzers frequency. Then you can tell by the frequency reading which way you need to go with the antenna to get it to the frequency you want it set at.

img_20150316_141035-1-jpg.15412


You can see how a Analyzer can be a useful tool for all your antennas whether matching correctly the manufactured ones or your home brew antennas.

Like all tools, they can be useful if you understand them and use them properly.
 
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you need to get the mfj meter at the feed point of the antenna and take your readings there. With and R of 70 what was X like? without the amp or anything In line? As its stands you have a bad impedance mismatch and your x value is way too high. Ylu may want to pull your antenna down and retune it or if you can get close to the feed point connect the mfj meter there and take your readings. JMHO.
 
If you cannot place the SWR meter or analyzer directly at the feedpoint use an electrical 1/2 wavelength of coax cable between it and the antenna. The readings will be the exact same thing however any other length of cable will affect the impedance reading on the analyzer. I have 1/2 electrical wavelength cables all made up for each amateur band from 80m up.
 
If you cannot place the SWR meter or analyzer directly at the feedpoint use an electrical 1/2 wavelength of coax cable between it and the antenna. The readings will be the exact same thing however any other length of cable will affect the impedance reading on the analyzer. I have 1/2 electrical wavelength cables all made up for each amateur band from 80m up.
Funny CK what were we talking about 16 posts posts ago?
 
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