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Re: AO-40 and Trees

On Mon, 4 Aug 2003 10:20, Michael T. Sheleheda wrote:
> Hello.
>     I have been making contacts on UO-14 with an arrow antenna for a while
> now and want to move up to AO-40.  I have a Kenwood TS-2000 and want to
> start building a half way decent station, but before I spend too much money
> on antennas and rotors, I have a question.
>     I have a row of 50-60 foot oak trees behind the house which I would
> have to aim through to hit AO-40.  I can work UO-14 through these trees
> with little signal loss, but what can I expect  when trying AO-40?


Hello Mike,

I faced exactly the same dilemma as yourself. I live in a valley and I'm 
surrounded by tall native eucalyptus trees. This what I eventually did.

I built a 2.5 metre tower and a rotating system from salvaged gears. I bought 
a somewhat battered and slightly rusted 1.8 metre dish and a 3731 down 
converter. I had absolutely no idea if the system would work or not.

At elevation angles that place the satellite above the trees I receive the 
beacon at no better than strength 7 above the noise. However, once the signal 
has to pass through the thickest parts of the trees then the signal strength 
is reduced to around strength 4. This is at an elevation angle of say 25 
degrees. I have made contacts down to 15 degrees but I have to listen very 
carefully. My horizon in this direction (west) is 10 degrees.

Once AO-40 is available during gentleman's hours I will aim my dish east. I 
have a 5 degree horizon in that direction and expect to hear a little better 
since the trees are further away (about 35 metres).

So, it can be done with minimal expenditure but it takes lots of effort and 


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