View Single Post
  #19   Report Post  
Old January 24th 06, 04:45 PM posted to rec.radio.amateur.antenna
 
Posts: n/a
Default Vertical on a tower

Well, there's the problem. You stopped your dipole where
your vertical started so any comparisons are bogus.


Bogus? How so?

Your
dipole was an NVIS antenna. :-)


And I want it to be.

It's not a fair comparison
since the vertical was given a 2x height advantage. (That's
like putting my three foot six inch grandson up against
Shaquelle O'Neal in basketball. :-) Put the dipole at 70
feet, like the vertical was, and see what happens.

I mounted both as high as they would go. I don't consider
the GP as having quite twice the height advantage due to
the current distribution.

The top of my vertical was at 53 ft. and my dipole was
one of its upper guy wires at about 50 feet so the two
heights were essentially opposite yours.

No , just different..

Which brings up another question. If the top of a vertical
is at a certain height, what height of dipole would be a fair
comparison?
Dunno...But max current on the GP as at the base..

It is certainly unfair to compare feedpoints
at the same height, like you did.


No, it isn't. I can compare any setup I like. I'm not
trying to be fair. I don't want both antennas to act
the same.

It may also be slightly
unfair to compare them at the same maximum heights, like I did.
It seems a fair comparison might be made when half the vertical
is lower than the dipole and half is higher than the dipole,
i.e. the height of the dipole is at the midpoint of the
monopole?

I don't think it matters a whole heck of a lot. I never intended
for my dipole to be a dx antenna. Thats the whole purpose
of putting up the GP. The dipole is for NVIS and medium
range. The GP is for long range.
MK