[NLRS] Microwaves today...

[Ford Peterson]

Mike wrote:

...SNIP...

> So, from our earlier contacts last summer and fall, where the humidity =
was
> 40 to 60% most of the time, my guess if it could have been in that =
range,
> then a QSO would have resulted.  Does anyone have a good and proven =
pathloss
> calculator taking into account antenna gain, NF, humidy, etc.?  I know =
I saw
> it somewhere but I dont have a clue where.  Would be intresting to =
crunch
> the numbers and see if calculations come somewhere close to real =
operation.

Mike,

I have a path loss calculator that I produced from an article in the =
March/April 1992 issue of EMC Test & Design.  No clue where that =
magazine got to, but the old MSDOS basic program still runs on my XP =
machine.  Many assumptions are implicit in the calculations.  And =
nowhere does humidity enter into the picture. =20

Here are the results of a 10400MHz path loss calculation. (dB, distance =
in miles)

070    0.007 miles
080    0.022
090    0.068
100    0.215
110    0.680
120    2.151
130    6.803
140  21.513
150  68.031
155 120.978
160 215.133
165 382.567
170 680.311

So there you have it.  156dB path loss at 138 or so miles.  I can =
produce the graph in dB increments, but let's face it, this is just an =
engineering approximation anyway.

Enjoy,

Ford-N0FP
ford@cmgate.com