On 11/27/2014 9:06 AM, bilou wrote:
"John S" wrote in message
...
Thoughts?

That is about 7 feet at 434 MHz; hope there is nothing in the way.

The target application is for a remote water level sensor in the
countryside. No problem with height there.

HI
At UHF total and permanent clearance of the Fresnel zone
is the rule for reliable results.
Directional antennas at both sides helps a lot too but higher is always
better
At such low height rain ,snow and even cutting the grass will produce
variations.

You don't know the particulars.

The angle of maximum radiation is about 6 degrees. At 1000 feet, I will
need a height of about 104 feet to be in the lowest (max radiation)
area. The remote site is about 80 feet below my receiver (a flood plane)
and the receiver antenna is about 20 feet above the point of reception.
It is why I chose the height of the antenna. Of course, this all remains
to be tested.