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Author Topic: Inverted V on steep hillside  (Read 2856 times)

Offline Antennae

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Inverted V on steep hillside
« on: June 02, 2014, 2109 UTC »
So if an inverted V is on level ground, it has a radiation pattern that goes up.  Say you have a steep hill and place the inverted V so that it is perpendicular to the angle of the slope.  The radiation pattern should then go at an angle and be useful for directional skip, no?  Possibly badass directional skip?
California Coast
RCVRs: Radio Shack DX-398 portable / SDR: Elad FDM S2
Antenna: usually a random wire with tuner

Offline redhat

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Re: Inverted V on steep hillside
« Reply #1 on: June 05, 2014, 0453 UTC »
Relative to its main lobes at 40 degrees, an inverted v has about 8 DB less radiation "straight up" which in theory would also make it a poor NVIS antenna.  It is however better than a low dipole, in this respect, having about 4 DB more radiation in the vertical direction.  Barring local terrain issues, the 1/4 wave vertical is usually going to be a better DX antenna, as its lobe elevation angle is much lower than a dipole, and has the added benefit of being omnidirectional.

Your mileage may vary, but that's what I've found.  I also like my verticals because they are quite portable, which is great for "field day" use.

+-RH
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WinRadio Excalibur/305 w/ a chi-town resonant loop, Kenwood KDC-U356 for mobile listening.
Please send QSL's and reception reports to xfmshortwave [at] gmail [d0t] com

Offline ChrisSmolinski

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Re: Inverted V on steep hillside
« Reply #2 on: June 05, 2014, 1053 UTC »
Have you had noise pickup issues with your verticals, redhat?
Chris Smolinski
Westminster, MD
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Offline redhat

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Re: Inverted V on steep hillside
« Reply #3 on: June 06, 2014, 0307 UTC »
I have observed it to be noisier than my inverted V, but I don't use the vertical much for reception ;)  The accepted notion that most man made noise is vertically polarized generally only refers to frequencies not intended for ionospheric propagation, ie VHF and above.  In all fairness, I haven't had the chance to compare the transmit vertical with, say, Farley's tuned loop side by side to determine relative noise level.  My suspicion is that all those who complain of verticals being noisy probably have a lot of common mode noise finding its way to the feedpoint, poor ground systems, severe local noise sources, or a combination of all the above.  Out in the country away from power lines and such, its quite a good RX antenna.

+-RH
Somewhere under the stars...
WinRadio Excalibur/305 w/ a chi-town resonant loop, Kenwood KDC-U356 for mobile listening.
Please send QSL's and reception reports to xfmshortwave [at] gmail [d0t] com

Offline Antennae

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Re: Inverted V on steep hillside
« Reply #4 on: June 07, 2014, 1609 UTC »
Chris, I had a 1/4 wave vertical with 4 radials 6 feet off the ground about 150' from the nearest house. It didn't pick up the noise from my house that I usually hear with my loop right next to my house. It was cut for 43meters and had no tuner. I connected my portable to its contacts with alligator clips. This is when there were some storms in the South (as I recall) in mid Feb. 2014. 
When I was only hooked up to the radials, I would hear the noise from the storms.  When I was only hooked up to the vertical wire, I didn't hear them so much.  When I was hooked up to both the wires sometimes I couldn't tell a difference. But sometimes both made the reception better.  This is storm noise I'm talking about receiving and I don't know if its polarized or not, its just my observations.

Without a tuner it was about as good as my loop that doesn't have a tuner.  I didn't compare it with the loop that much as the wires broke.
California Coast
RCVRs: Radio Shack DX-398 portable / SDR: Elad FDM S2
Antenna: usually a random wire with tuner

Offline Pigmeat

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Re: Inverted V on steep hillside
« Reply #5 on: June 11, 2014, 2010 UTC »
I used to use inverted v's  on steep hillsides, as that's about all there is around here.

I found that they work best when you're on bluff or a cliff with a steep vertical drop.You set the antenna up about 3-4 yards from edge of the bluff, get it up in the trees about 30 feet at it's apex. The antenna being so close to the edge of the bluff "sees" the height of the antenna as 30 feet plus the height of the drop, (in the direction the bluff.)

It's a simple, easy trick to get a lot of extra height and put out a better signal w/o a lot of work.

Offline Antennae

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Re: Inverted V on steep hillside
« Reply #6 on: June 12, 2014, 0250 UTC »
Thanks Pigmeat,
Cool, I appreciate effective easy things.  And so does the venerable Bill Gates: I choose a lazy person to do a hard job. Because a lazy person will find an easy way to do it. I guess I think you're lazy. But in a good way.
PS Are you a hillbilly?  ;)


California Coast
RCVRs: Radio Shack DX-398 portable / SDR: Elad FDM S2
Antenna: usually a random wire with tuner

Offline Pigmeat

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Re: Inverted V on steep hillside
« Reply #7 on: June 12, 2014, 2021 UTC »
We prefer "Appalachian-Americans" these days.