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[W9IQ]

I would suggest simply reversing the connection between the tuner and the ladder line from the antenna. It may change the SWR results.

- Glenn W9IQ

[WA5YOM]

Certainly a cleaner installation....and meets spec, whereas the concrete pedestal did not....
I am not sure what results I expected....but at least better than it was...if the theory of the design is even close to valid.....
Yeah....bacically the suggested modification turns it into a standard vertical with ground.......just no radials

It isn't hard to.....the lowest section of the pole....has a screw terminal....for connection....and I already have the ground rod in place....just not connected...I can try this...probably wouldn't take an hour to do......if that long.....

I will try that modification this weekend....when I can find some time...

I am not sure at what swr level the tuner is supposed to function.....but it seems like it has to be pretty high before it tries...

Yes..I did a complete system reset and erased all the memories.....

It isn't hard to do......and I may try that again....just to see if it improves.....

Glen,

Are you referring to the reversing the upper and lower half connections?

I can, but based on the design....the lower half is supposed to be the shield (-) and the upper half is supposed to be the center connection on the PL259 (+)..

I have checked the polarity before...but I probably should check again....

[RFRY]

...
Are you referring to the reversing the upper and lower half connections?

I can, but based on the design....the lower half is supposed to be the shield (-) and the upper half is supposed to be the center connection on the PL259 (+)..

I have checked the polarity before...but I probably should check again....

Remember that the feedpoints of an antenna system are connected to a device that produces/uses alternating r-f current & voltage (+ and - ), not direct r-f current & voltage (+ or -).

[W9IQ]

The transmission line from the antenna is highly imbalanced. It is not acting as a transmission line should.

But if you follow the flawed logic of the designer and presume it to be balanced, the tuner will imbalance it no matter how well you float the tuner. This is because a balanced transmission line requires an equal magnitude of current of opposite phase between the two conductors. The tuner inserts an inductor in series with only one transmission line wire (remember ELI the ICE man?). That is guaranteed to make the line imbalanced if it ever was, as the designer incorrectly imagined.

The lesson is that a single sided L tuner can never properly drive a balanced line without the use of a good current balun on its output.

- Glenn W9IQ

[WA5YOM]

Glen...

When I first installed it....I did not use the remote antenna tuner, thus the balun was on the outout of my shack tuner.......I did have slight success tuning on 80........but nearly nothing was radiated......
Also, that configuration.......the atu was grounded......
I switched to the remote atu......then set it up...just as the manufacturer requires....at that is where I am today....
I can move the balun back to the atu output.....and see what it does.....

[W9IQ]

Measure the R and X for each band at the input to the ladderline from the antenna (ATU disconnected) before anything else.

- Glenn W9IQ

[WA5YOM]

Well....moving the Balun...recreates the way it performed before I installed the remote atu.....tunes on the low end of 80 and 40.....haven't tried the other bands...

I will have to build and adapter to measure the antenna...at the twin lead....since the analyzer only has a pl259 connection......

[WA5YOM]

3.5 mhz, R=7938.71 ohms, X= +3175.87  ohms
7 mhz, R=11.43 ohms, X= -250.71 ohms
10.1 mhz, R= 16.28 ohms, X= -97.43 ohms
14 mhz, R= 98.34 ohms, X= +30.13 ohms
18.068 mhz, R= 52 ohms, X= +56.57 ohms
21 mhz, R= 37.44 ohms, +184.67 ohms
24.89 mhz, R= 106.99 ohms, X= +551.38 ohms
28 mhz, R= 1025.91 ohms, X= +1986.96 ohms
50.1 mhz, R= 73.34 ohms, X= -86.45 ohms

I did not run a test on 160

The values are charted across each band, so the above values represent one frequency....the start of eaxh band segment.
The plot includes, SWR, Z, R, X, Return loss and Phase angle.
Includes Smith chart for Impedence and S11

The analyzer, MFJ-226, was connected directly to the antenna twin lead, as designed (OCF).

Tim
wa5yom

[W9IQ]

Tim,

Based on your measurements, here are my observations:



The L and C values in the chart are the component values needed to match the impedance to 50 ohms in the low pass L match configuration used in your tuner.

• On 80 meters the tuner does not have sufficient range. It is also possible to damage it due to high voltage
  
  
• On 40 meters, the loss within the tuner could be sufficient so as to cause damage due to excessive heat. This is difficult to pinpoint due to actual inductor Q. For this chart, I estimated the inductor Q to be 100
  
  
• On 10 meters, there is also the danger of high voltage and it has moderate loss
  
  
• The tuner is not rated for 6 meters
  
  
• The tuner should provide a reasonable match on the other bands although it may not be an SWR of 1

I suspect that if you put your 1:1 balun on the output of the tuner that it would find a reasonable match except on those bands with an indicated note. I would also recommend a common mode choke / 1:1 current balun on the coax before it enters the shack.

You may find some better results by varying the length or type of the feedline between the tuner and the antenna as this will change the impedance transformation that you are seeing.

- Glenn W9IQ

[WA5YOM]

Thanks for your analysis...
Yeah, after I saw the data.....I could see that 80 and 10....was probably a no-go...which is why I did not even try to test 160......I didn't conclude that 40....could cause a problem....but I did see that the SWR would not come down....
I tested 6....only because the antenna was supposed to work on 6......
So, basically....the low bands were my desire....in the first place....and it is useless on those frequencies...Looks like I have an extremely expensive Flagpole...
Do you think my results are caused by something in my installation?
Or, will this design ever meet the manufacturers claims...
So, what do you think the results would be if I modify the antenna to a standard vertical with ground plain?
Recall...I moved the 1:1 Choke Balun to the antenna side of the tuner before this test....results were so---so....
Tim
wa5yom

[WA5YOM]

I am not sure that modifying the antenna for 80 will ever work without electrically changing the overall length of the pole...

[W9IQ]

I would agree, Tim. No doubt you could add a high Q inductor at the base to make the current vertical length a reasonable match on 80. But I don't think you would be happy with its performance. But if you have no other options, why not?

You could add a loaded section on top or perhaps a large top hat to improve its performance in a vertical configuration but that is quite a deviation from the aluminum you currently have in the air.

There is lots of good experience on the forum so perhaps you could indicate how far, or not, you are willing to go. I am sure ideas will then be forthcoming.

- Glenn W9IQ

[WA5YOM]

I have the option of increasing the length in 4 ft increments.......which would land on 32 ft or 36 ft.......with the tuner......that should get me close......for 80 meters.....might have to turn it into a standard vertical....and it might still improve on the original design concept....
I am mostly concerned about throwing more money into this......but right now all I have is a useless expensive stick in the ground.....I might be better off dismantling it.... reselling it,,,and just take my losses...and move on.....

[WA5YOM]

For experimentation purposes I could install the loading coil I made and see what happens......narrow swr....for the moment is fine.......since my main interest is the cw and digital portion of the band........

[WA5YOM]

upon more research....connecting with others that have the antenna..reading reviews...most experience the same problems... don't think anyone is getting it to work as advertised....
Some are using a 4:1 balun....and their shack tuner...I might try that.....will have to buy one...