Thread: NVIS and VHF?
View Single Post
  #55   Report Post  
Old June 1st 11, 10:48 PM posted to rec.radio.amateur.antenna
'Captain' Kirk DeHaan 'Captain' Kirk DeHaan is offline
external usenet poster
 
First recorded activity by RadioBanter: May 2011
Posts: 11
Default NVIS and VHF? (Update)

'Captain' Kirk DeHaan said the following on 5/22/2011 11:04 AM:
I'm living in a wooded area and am trying to hit our club repeater
reliably. It's cloudy now so I'm and getting a bit of ducting but I have
a lot of trees, mostly poplars, in the direct path. I would have a line
of sight if not for the trees as I'm up enough in altitude. I can cut
the trees, they're mine, but finding the right ones is difficult and i
don't want to waste the whole grove.

I go from keying the repeater with no intelligible signal to not being
able to hit it. Today I actually have an S meter reading due to the
clouds. I am currently using a J-pole and will put up a Yagi soon but
wonder if NVIS would work on 2m? I have only seen references to it being
applied in HF.

'Captain' Kirk DeHaan
N6SXR


I am still working on finding where the problem is. I pulled the J-pole
down and checked the resistance of the separate connections. I didn't
want to pull it apart if not necessary. Everything showed 0.0 to 0.1
ohms. Seems fine to me. I then cleaned the connector as throughly as
possible using emory cloth inside and dremeled the outside with a fine
wire brush. There was a small amount of oxidation and it appeared much
cleaner and brighter after. I also straightened the two elements but
they were not really that bent. You had to look down the long axis to
see any deviation. They are as straight as they are going to get but I
can't believe that would make much difference.

After all this I put it back up to it's original height. There was not
discernible change. I was almost unreadable at the repeater.

Next I pushed up my mast a few feet more. It is a 50' pushup that
normally requires guy wires. I am not using any so I am leaving
considerable overlap of the sections. I would estimate it is up around
32'. Even in high winds here I saw little deflection with just the
J-pole. The 3 or 4 feet I pushed it up gave me a little bit of
improvement. When I win the lottery I'll get a 100' tower put up.
Guess I'm stuck with this then :-)

I still think it is the trees and have taken a picture from the roof
peak towards the repeater so you can see what I am dealing with.

http://www.ncc-1701a.net/Ham Radio/ForestObstruction.jpg

It is deceiving as there are many more trees behind this line on my
neighbors property. I wouldn't even think of asking him to cut any.
They are money in the bank for him.

--
'Captain' Kirk DeHaan
N6SXR

"Beam me up Scotty, there's no intelligent life here"