I have a multi band dipole strung up as an inverted Vee from my 80 ft tower.
I have a run-out of only 50 ft due to the small size/shape of my lot. If I
pull the top of the Vee all the way to the top of the tower, the Vee gets
quite steep - only 30 degrees. Of course I can make the angle wider by
lowering the apex of the Vee. So what is more important, height or slope?
What would be the best compromise? BTW, the antenna is an Alpha Delta DX-LB
Plus 160M, 80M, 40M, 20M, 10M.

--
Bob D. ND9B

On Sat, 7 Jul 2007 12:17:13 -0400, "Bob D."
wrote:

So what is more important, height or slope?

Hi Bob,

Go for height.

What would be the best compromise?

With 160-10M coverage, you are already at compromise.

I presume by the statement about 30 degrees, that this is the included
angle of the V. I can't imagine you have enough range of variation to
make much difference there (if in fact you would see any improvement
or loss for the attempt if you did have the range).

A simple test at 160M would be to see how broad the match is. The
broader it is, then it is too close to earth (more loss). The high
bands should work quite well (even if you need a tuner).

73's
Richard Clark, KB7QHC

On Sat, 7 Jul 2007 12:17:13 -0400, "Bob D."
wrote:

I have a multi band dipole strung up as an inverted Vee from my 80 ft tower.
I have a run-out of only 50 ft due to the small size/shape of my lot. If I
pull the top of the Vee all the way to the top of the tower, the Vee gets
quite steep - only 30 degrees. Of course I can make the angle wider by
lowering the apex of the Vee. So what is more important, height or slope?
What would be the best compromise? BTW, the antenna is an Alpha Delta DX-LB
Plus 160M, 80M, 40M, 20M, 10M.


http://www.cebik.com/wire/vang.html

Here are your trades:

An inverted vee produces a broadside elevation pattern that's very
similar to that of a dipole at the inverted vee's "average height"(*).
This "average height" is the height of the wire at a point 1/3 of the
way from the center to an end.

What you gain by increasing the included angle are increased bandwidth,
easier matching, and potentially lower loss (higher efficiency). When
you decrease the included angle below about 90 degrees, the bandwidth
narrows and the impedance drops rapidly. The lower impedance can
potentially result in increased loss, both in the wire and in the
matching circuitry.

An antenna modeling program can tell you quantitatively what the pattern
and feedpoint impedance would be for each possible configuration. It's
up to you to decide what you want to sacrifice.

(*) The "average height" is the height at which the integral of the
current along the wire is the same above and below. The one-third figure
is exact if the current is sinusoidally distributed, which is a very
good approximation for a half wave antenna.

Roy Lewallen, W7EL

Bob D. wrote:
I have a multi band dipole strung up as an inverted Vee from my 80 ft tower.
I have a run-out of only 50 ft due to the small size/shape of my lot. If I
pull the top of the Vee all the way to the top of the tower, the Vee gets
quite steep - only 30 degrees. Of course I can make the angle wider by
lowering the apex of the Vee. So what is more important, height or slope?
What would be the best compromise? BTW, the antenna is an Alpha Delta DX-LB
Plus 160M, 80M, 40M, 20M, 10M.