Expectations for 135 foot dipole
I am helping to install a 135 foot dipole on a hillside for HF
activity. The antenna will be at least 45 feet from the ground in any
direction. I can believe EZNEC so far as the effects of ground on
impedance. but I am at a loss when it comes to considering the
patterns on the various bands. The ridge is about 200 feet from the
antenna.
This is for a club member who recently upgraded to General Class.
Since the ridge is close to the same height and south of the antenna,
I am guessing that the computed charts will be a good representation
of the northern half of the antenna. NVIS should not change much. The
terrain may work as a reflector for over the pole operation. I am
afraid the antenna will be of little use to the south.
I expect we will eventually need to do the best we can with an antenna
on the top of the ridge. When the snow melts I will try to climb the
ridge for a look-see. It will likely be difficult to install due the
dense trees.
Any comments, advice, suggestions etc. are appreciated!
John Ferrell W8CCW
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