Hi Tim, I will check out the date and elevation angles on both ends. It may
well be that the angles are not compatible for eme. To work, it would have
to be approaching moonset for ES5TV and shortly after moonrise for you.
The elevation changes about .2 degrees per minute so 5 degrees elevation
happens about 25 minutes before moonset and after moonrise.
On 6m, eme is often done with the 2nd and 3rd elevation lobe so you might
want to do a computer run for both ends to see if one of the higher lobes
can be used. This is pretty tedious stuff and explains why many skeds are
just done multiple times to see if happy coincidence happens empirically. Of
course we all do some crazy things in the name of being part of a "first".
On the ionosphere issue, I am guessing that an open band will attenuate the
eme path quite a bit. One way to get a handle on this is to monitor
background galactic noise on a dead band vs open band. The difference in noise
levels would be due to attenuation differences as the noise passes through
the ionosphere.
I will let you know about the numbers for April 27.
73,
Gerald K5GW
In a message dated 2/6/2013 7:58:49 A.M. Pacific Standard Time,
k3lr@k3lr.com writes:
Hello Tonno,
If April 27th works out - I can be very ready to try this. That is a good
open day for me. Maybe Gerald, K5GW can double check path loss calculations
for EME on 21 MHz at that day/time for both QTH's to see if this 10 minute
window might work on April 27 15 meter EME QSO according to his program.
We can have a multi Skype session web link going on April 27 - so guys can
see both ES5TV and K3LR ends live during the experiment EME time.
The coordinates on the K3LR QRZ.com page have 1 second accuracy for the 15
meter tower. At K3LR, the four high OWA long boom stacked array has modeled
gain (with ground) of 21.9 dBd at a take of angle of 4.5 degrees. The feed
system is very low loss - 200 feet of 1 5/8" Andrews Heliax, so most of the
1500 watts in the shack makes it to the antenna port power divider mounted
on the tower at the mid point of the array.
I do not know if 15 meter EME be done during daylight hours when the band
is
likely to be open. Others may know that answer.
73,
Tim K3LR
-----Original Message-----
From: Tõnno Vähk [mailto:tonno.vahk@gmail.com]
Sent: Wednesday, February 06, 2013 8:57 AM
To: k3lr@k3lr.com; towertalk@contesting.com
Subject: RE: [TowerTalk] 15m monster finally up - EME and Video
Thanks Tim,
I got a good program suggestion - MoonSked by GM4JJJ.
Not being very familiar with this stuff yet I can calculate windows for us.
Basically I am looking for moments when the moon is from 0 to 5 degrees in
both locations and both are in darkness. It is not an easy criteria to
fulfill.
The first slight chance opens on April 27 from ca 0210 to 0220z while I
have
sunrise on 0230z already which might mean the band is already open at 0210.
In summer we almost don't have common darkness so I guess that rules summer
out. And now looking all throughout the year there is no other time.
So we only seem to have a 10 minute window in the whole year, Tim!:)
Is my logic correct here? Or could it be that it could be done during
sunlight? In the sunspot minimum perhaps?
73
tonno
-----Original Message-----
From: Tim Duffy [mailto:k3lr@k3lr.com]
Sent: Tuesday, February 05, 2013 11:50 PM
To: 'Tõnno Vähk'; towertalk@contesting.com
Subject: RE: [TowerTalk] 15m monster finally up - EME and Video
Hello Tonno!
Congrats on a very FB installation! Your EME video is outstanding!
If the moon times line up with you, there is enough gain with the 15 meter
28 element array at K3LR to do EME. I'd love to try a two way 15 meter
QSO.
http://www.k3lr.com/2007/photos/15mtower.jpg
http://www.k3lr.com/2011/CQ11CW/IMG_3300.jpg
73,
Tim K3LR
-----Original Message-----
From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of
Tõnno
Vähk
Sent: Tuesday, February 05, 2013 7:49 AM
To: towertalk@contesting.com
Subject: Re: [TowerTalk] 15m monster finally up - EME and Video
Now all I have to do is to find someone interested in attempting real 15m
EME QSO (anyone done that before?) who would have coinciding sunset/sunrise
and high gain antenna on 15m.
73
Tonno
ES5TV
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