Stacks

[Jay Kesterson K0GU x6826]

This is a Email conversation Eric and I had. We decided to post it here
to see if anyone has comments.

Hi Eric, 
  Was pondering the difference between LPL and RM when I wrote my stack
article. I sort of figured that RM was probably only using their lower 2
15 meter antennas most of the opening to EU. On the LPL fixed EU stack
are you able to switch between the upper and lower antenna (to see if the
lower antenna by itself is better)? Since most of the time RM uses 4/4
you have them out gunned antenna wise with the 5/5. What is the height
of RMs two lower 15s? I was just guessing that maybe the LPL stack
was too high. A local has a 15 meter antenna at 80 ft and another at
about 60 feet. The 60 foot antenna is a much better domestic antenna,
and we are only a bit closer to the east coast than you are to EU.
I am just trying to figure out the difference between the two stations.

Its a bit different out here, its 4000+ miles to western EU. But still fairly
easy to get a antenna up too high when there is lots of flux.

73, Jay Kesterson  K0GU     jayk at fc.hp.com


>Jay --
>
>   Thanks for your note.  If you would agree, please forward it plus my
>response here to the system, so that others can read/comment/provide more
>insight.  (I did not want to forward your message unilaterally.)
>
>   On the W3LPL fixed EU stack, there is no provision for selecting any one
>of the antennas individually.
>
>   N2RM's lower two antennas are at essentially the same height as the W3LPL
>EU stack (within about 3 meters, as I recall).
>
>   It would be an interesting test to try driving W3LPL's lowest antenna
>only towards Europe during the height of the opening, and see if the 
>respondents rated it differently.  But someone else has pointed out that,
>in the middle of the opening, there may not be much difference between
>being 20 dB over S9 and 25 dB over S9.  (I feel that, unfortunately, this
>is relative... there is a LOT of difference if the QRM or inter-mod level
>in someone's receiver is 23 dB over S9 ... which can easily occur when a
>European station is listening for stateside with a tribander at 10m above
>ground, and there are plenty of other loud European and western Asian 
>stations on the band at the same time.  W3LPL and others have commented
>that having a clear frequency on SSB makes a world of difference in terms
>of the rates achievable.)
>
>   The situation for working Europe from Colorado must be a world of 
>difference.  You will be struggling with all the problems of a path which
>goes right through the auroral ring for a substantial portion of its 
>length ... very similar to the struggles that we in the mid-Atlantic states
>have in working Japan.
>
>   I would be VERY INTERESTED to learn from the experiences of the Russian
>contesters who are now part of this system.  Many of them have to 
>contend with the auroral paths a lot of the time.  I wonder what knowledge
>they have gained over the years -- maybe they have some new ideas??
>
>-- eric!  K3NA

Perhaps KN2M can tell us what difference he sees on his 100'/50' 15 meter
stack during the middle of the EU opening.

Jay  K0GU