[NLRS] 24 GHz at KM0T - Grid #11!

[Mike King - KM0T]

Hi all, hope your all getting your Christmas shopping done and keeping an 
eye out for those eavesdropping airplanes :)



FYI - Did some 24 GHz this morning.  Gene - N0DQS and I had been trying for 
Grid #11 for over a year now, well we finally made it today!



>From my roof top to EN21lx, we had not made it in two previous attempts. 
With the troubles we had been having, we were thinking it may be attributed 
to a school "bus barn" that was about 1/3 of a mile away from me, where the 
metal sloping roof was about 10 feet taller in elevation than when I was 
perched on my rooftop with the tripod and dish.



This led me to the investigation of "Fresnel zones" and that sort of stuff, 
which indicated that lots of my signal my have indeed been obstructed.  We 
also were thinking that some elevation on Genes side of the path, about 20 
to 25 miles out may have been a problem too.



In past attempts, we had tried the total path, nothing heard, then Gene came 
in closer while I remained on the roof.  Path about 50 miles.  No problems 
here at that distance.  Then he would move out to about 70 miles, on the 
close side of his potential obstructions, again no problem.  With that, I 
had my dish on the right heading, as he selected locations on the same 
heading.  Then Gene moved back to the original location in EN21lx, where we 
again failed to hear anything.



The previous two attempts were when conditions were much warmer, and corn 
was in the field.



Today, conditions were somewhat brutal.  We thought about going out 
yesterday, but with such a nice day, we had other things going on.  So, we 
hoped that things would be nice today as well, no such luck!



A bit of planning discussion led to reversing the attempt process.  I 
decided to go east of my QTH to see if we could make contact, taking the 
"bus barn" out of play and seeing if the potential obstruction 20 to 25 
miles from Gene's location were a factor.



We hooked up right away while I was in EN23ac, about 80 miles with 539 to 
559 signals.  It was a good surprise to find each other right away as the 24 
GHz stuff had not been powered up for some time.



I then moved back to Sioux Center, and went to a hill just east of town, 
pretty much on path with where it would be if I was on my house, just a mile 
farther into town.  I had a good elevation at this spot and good horizon, a 
small dirt road with a farm in the background behind me with about 100 cows 
looking at me wondering what I was up too!



We found each other here in about 5 minutes, 419 to 519 signals, some 
difficulty with QSB.  We discussed the next option, which was we would never 
know unless I got on the roof and tried!



So I got back to the house, put the ladder up and put the gear up on the 
roof.  Gene pretty much kept his dish on the path it was and we found each 
other in about 5 minutes.  The frequency was moving around pretty good, but 
we had a good idea where each other was since the temperature was fairly 
constant.



Signals were just a bit better, pretty solid 519 with QSB.  144 degrees was 
my heading as projected on my KVH datascope, with about +/- 1 degree where 
signal could be heard.  Elevation appeared to peak about .7 degrees above 
zero.  Not sure if this is the sweet spot of the dish or if elevation was a 
factor.  Path is about 93 miles, not our longest, but a new grid!



Interestingly enough, the temp from 10AM to 12 noon was 32 to 36 degrees, 
where the DP was 28 to 32 degrees.  Local NOAA weather station in Orange 
City reported 87% RH at 12:35 PM, which was the time of our contact.  I had 
checked the RH early in the morning before I left, and it was 88%.  So, 
temps were pretty much constant as well as the RH, which was pretty high. 
Frost was on the roofs around here all morning.  No snow anywhere to be 
found around here.



Haze was always on the horizon, not bad or thick, but one could see it. 
NOAA reported 10 mile visibility.  Winds were constant all morning, 15 MPH 
from the east to the south east.  So this cold, wet wind made my hands 
pretty cold, especially when I got to the final spot up on the roof!  Glad 
it went well, it was getting pretty cold up there!



So, Im not sure I can really draw any concrete conclusions from all this. 
They say that it should be dry, not humid for DX, but it seems that from 
what we have done in the past, some humidity is a good thing in order to 
create a scattering medium.  I wonder if this dry path stuff is more in line 
when you're trying non-obstructed paths, such as mountaintop to mountaintop.



It also appeared that the "bus barn" and the tall elevation 20 to 25 miles 
out from Gene's location in EN21lx was not a total factor.  So, with that, 
one can conclude that either, pointing, frequency or Corn / foliage was the 
problem before.



Im going with Corn!



73 and CUL



Mike - KM0T EN13vc