Topband: Inverted L improvement question - Part 2

[Grant Saviers]

Modeling I've done shows it a bad idea to have in ground and elevated 
radials connected together, but that is not clear from what you 
described.  Then with the elevated separate, moving the feedpoint up at 
least 8', to 12' is better and elevated radials run out at that height. 
I think it is a tossup if the "flying V" feed is used - ie gain some 
vertical wire length by feeding near ground and then angle the wires to 
the the elevated ones say at 45 degrees.  It doesn't hurt to have the 
buried radials below the elevated but doesn't help either according to 
NEC4.2 models I've tried.  The elevated ones shield the currents enough 
from the ground in the near field.

Check out what N6LF has to say about elevated radials (if you haven't 
already)  antennasbyn6lf.com

Then develop an swr curve with 5 watts from your rig.  Better than nothing.

Borrow a different antenna analyzer to try or put a quality BCB filter 
on the input.  You need one anyway.  A two port VNA can calibrate out 
the filter.

It is also hard to compare antennas unless the A/B testing is real time. 
  This week proves that on 160, one night nada to EU, Thur night was 
pretty good and I missed the killer opening on Wed according to PNW 
reports.

Grant KZ1W

On 12/28/2018 15:35 PM, Todd Goins wrote:
> I originally started this thread and I want to once again thank everyone
> who provided input and advise both privately and on the reflector.
> 
> So the 100' tall vertical with the 30' horizontal loading wire works
> **horribly**. I have about a week with it now every evening and it is much,
> much poorer transmitting (and receiving, as expected I guess) than the 43'
> vertical with the 90' horizontal.
> 
> Since everyone was united in the opinion that I needed a dedicated
> receiving antenna I put out a 200' BOG (pointing east) with the transformer
> and terminating resistor from DXEngineering. The BOG is really quiet
> (S1-S2) compared to the verticals and it hears "okay" but I wouldn't say it
> was great by any means. The Stew Perry tomorrow will give me better chance
> to evaluate it.
> 
> Back to the 100' vertical. Since it wasn't working being tied into the
> buried radial field I was using for the 43' (PSK Reported showed dreadful
> performance) I decided to take a different approach and made it have an
> elevated feed point at about 7' above ground and I ran three 130' elevated
> (also around 6' to 7' high) counterpoise wires. This antenna works a little
> better but still not nearly as good as the 43'.
> 
> Several people asked me to make R/Z measurements of the antenna at the feed
> point. I'd love to provide that info but my Comet CAA-500 MarkII antenna
> analyzer is being totally killed on 160m by a 27.5KW AM broadcast station
> that is about 2 miles from my QTH. It will not work. The analyzer has been
> fine on 6-40m and sometimes works on 80m but 160 is no-go. So I can't get
> the reactance and resistance values you all wanted.
> 
> So, here is my question. The one easy modification I can make to the
> antenna, now that I have elevated radials connected, is that I can elevate
> the feed point. I can raise it to about any height necessary. Would this
> make any difference? I would lengthen the horizontal wire by whatever
> distance I raised the feed point, right? Any ideas or am I just chasing my
> tail?
> 
> Thanks for reading and any advise you can give.
> 73,
> Todd - NR7RR
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