[TowerTalk] 15m monster finally up - EME and Video

Tue Feb 5 11:37:03 EST 2013

Hi All, the round trip time for EME signals is about 2 1/2 seconds so it is 
 easy to determine the path.

73,
Gerald K5GW
eme active on 6m, 2m, 70cm, 23cm, 13cm, 9cm, 6cm and 3cm; something is  
constantly broken!

In a message dated 2/5/2013 6:44:25 A.M. Pacific Standard Time,  
draxfelton at gmail.com writes:

How do  you know you didn't ionosonde yourself?  

Sent from my  iPhone

On Feb 5, 2013, at 8:49 AM, Tõnno Vähk  <tonno.vahk at gmail.com> wrote:

> Hi,
> 
> 
>  
> After two fruitless attempts at moonrise I got EME QSO with myself  done
> during moonset.
> 
> 
> 
> Here is the  video of the best minute out of ca 10 minute period the 
signals
> were  audible with strong QSB on January 13th, from 1615 to 1625z ca 2 
hours
>  after sunset:
> 
> 
> 
>  <http://youtu.be/QCP0kisTbME> http://youtu.be/QCP0kisTbME
>  
> 
> 
> Moon was setting at ca 243 degrees azimuth and the  signals were audible
> while the moon was from 3.3 to 2.2 degrees of  elevation peaking at 2.6
> degrees. Antenna was pointing within 3  degrees of the correct direction.
> Radio: FTDX5000 + ACOM2000A.
>  
> 
> 
> It is noteworhty that the band was not 100% closed  as even some SA 
signals
> were heard. Also the amazing strength of the  signals at expecially the 
3rd
> time the signals come back is probably  also attributable to some ground 
gain
> at this elevation.
>  
> 
> 
> I wish I had also tried SSB and maybe the 4 high  tribander stack for
> comparison but was too excited to remember. Should  also try if changing 
the
> radiation angle to say even 30 degrees would  allow hearing moonbounce 
from
> that elevation. Next timeJ
>  
> 
> 
> 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.
>  
> 
> 
> Can anyone recommend a good program that would  picture moon grayline 
(like
> DX Atlas for sun) that would enable to  easily identify possible paths for
> EME at any given time/day?
>  
> 
> 
> Here is also the high resolution video of the tower  erection put 
together by
> ES5PC. It also includes the very first QSO  with the new stack with Paul,
> K8PO:
> 
> 
> 
>  http://youtu.be/Z9fDlbIFhMs
> 
> 
> 
> I have also  made tests regarding the use of different elevation angles 
(by
>  shifting the antenna pairs 180 degrees out of phase) and the first  
results
> are very interesting. Proving that for DX normally the lowest  4 degrees 
is
> best but even for DX sometimes 7 or 10 degrees is  noticably better 
bringing
> an otherwise not audible signal out from the  noise. The same is true 
about
> some EU signals that peaked at 15  degrees while almost not being audible 
on
> low angles. So I will do  more testing but I am more convinced now that 
even
> in contest the  switching of angles might be useful trying to get a weak
> signal out  from the noise and high angles are sometimes very necessary.
> 
>  
> 
> 73
> 
> Tonno
> 
> ES5TV
>  
> 
> 
> 
> 
> From: Tõnno Vähk  [mailto:tonno.vahk at gafm.ee] 
> Sent: Tuesday, September 25, 2012 9:48  PM
> To: towertalk at contesting.com; cq-contest at contesting.com
> Cc:  es5tv at erau.ee
> Subject: 15m monster finally up
> 
>  
> 
> I am happy to inform all friends that a project of last 4-5  years was
> completed during the last weekend at ES5TV KO38CS central ES  QTH and a
> double H frame on 15m was finally erected what is probably  one of the
> biggest 15m setups in the world today.
> 
>  
> 
> See the full 2-day gallery at:
> 
>  http://pontu.eenet.ee/es5tv/
> 
> 
> 
> Go to the last  16th page if you wish to see the final product right awayJ
> 
>  
> 
> 70 meters high tower carries 8 5-element 15m yagis as pairs  separated
> horizontally by 12 meter distance and vertical stacking is  14 meters. The
> heights of the antenna pairs are 64, 50, 36 and 22  meters.
> 
> 
> 
> Antennas are Optibeam  OB5-15:
> 
>  http://www.optibeam.info/index.php?article_id=76
>  <http://www.optibeam.info/index.php?article_id=76&clang=1>  &clang=1
> 
> 
> 
> Tower is produced by  4O3A/YT3M: 
> 
>  http://www.4o3a.com/index.php?option=com_content
>  <http://www.4o3a.com/index.php?op
tion=com_content&view=category&layout=blog&
>  id=99&Itemid=499>  &view=category&layout=blog&id=99&Itemid=499
> 
>  
> 
> Model shows ca 16 dbd free space gain and almost 24 dbi gain  at 4 degrees
> over real ground. Beamwidth is less than 30 degrees.  Testing has been so 
far
> limited but the results confirm exactly the  modelling results. Pattern
> measured with signal generator and SDR was  almost identical to what the
> computer suggests and signal levels drop  ca 12 db when antenna is 20 
degrees
> off and already 20 db when 25  degrees off the correct direction. There is
> huge -50db+ null at 90  degrees confirmed with real measurements (!) and 
ca
> -20-30 db signal  drop on the other directions.
> 
> 
> 
> First  comparisons with my best antenna so far (4 high tribander stack) 
show
>  ca 10 db advantage to US when pointed right. That is huge of course.  At 
 the
> same time east coast and west coast can’t be covered with one  directionJ
> 
> 
> 
> The stack will have phase  switching capability which allows any pair of 
the
> 4 to be switched out  of phase to change the radiation angle. 
Pre-configured
> steps are 4, 7,  10, 15, 30 degrees while maintaining most of the gain as 
all
> antennas  are always connected. The phase switching is not yet connected 
but
>  will be very interesting to see the results and to get some real  
insights
> into how the different angles play.
> 
> 
>  
> We briefly tried to hear the moonbounce when the moon was on horizon  but 
did
> not succeed yet. But 15m was wide open and signals probably  did not
> penetrate the ionosphere. I still hope to be able to complete  some EME 
QSOs
> with the stackJ
> 
> 
> 
> CQWW  RTTY on the coming weekend will be the first contest for the 
monster.
>  Let me know how ES9C will sound on 15 meters. As the rotating is still
>  manual will keep it either to US or JA.
> 
> 
> 
>  73
> 
> Tonno
> 
> ES5TV
> 
> 
>  
> 
> 
> 
> 
> 
> 
>  _______________________________________________
> 
> 
>  
> _______________________________________________
> TowerTalk  mailing list
> TowerTalk at contesting.com
>  http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________

_______________________________________________
TowerTalk  mailing  list
TowerTalk at contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk