Topband: elevated radial symetry and layout

[Jeff Blaine]

Update on this project.

The guy doing my brush cutting has an auger attachment so putting down holes 
will be easy.  That opens the door to sticking another 4 poles out on the 
corners.  That would allow 8 radials per vertical in some combination.  I'm 
going to have him drill the holes and I'll stick in the posts.  But not sure 
if I will use them at the moment.

In EZNEC, the currents for the 8 radial variation are not even as in the 
case of the 4-per variation.  I need to dig into it more but I do think the 
ideal distribution is to have even currents across radials and in the 
4-square you won't get that.  The result was confirmed using the NEC4 engine 
as well.

Which means going from the 4 to the 8 case is not straight forward (as one 
of the guys already suggested).  It could also be that my assumption of even 
currents as an ideal - or my model - or something else is wrong.

With the poles I can play with it down the road.  I do have the W8WWV RVM 
system so measuring the radial current/phase is something that would be 
interesting to look into.

73/jeff/ac0c
www.ac0c.com
alpha-charlie-zero-charlie

-----Original Message----- 
From: Jeff Blaine
Sent: Wednesday, September 12, 2012 1:02 PM
To: David Novoa, W4DN ; topband at contesting.com
Subject: Re: Topband: elevated radial symetry and layout

Gentlemen, thanks for the offline comments.

And yes, I do understand and agree that more radials leads to less
individual radial dependence.  NL's QEX articles show that in the graphs
which is very interesting.  And also that a ground mounted screen is less
sensitive yet.

The current install is a temporary setup just to carry through this contest
season and into next year when I can get the tree work done to clear the
final resting place.  So 4 is the magic number.  And the question is how to
lay out those few to get the best overall symmetrical pattern among the 4
verticals in the array.

Sorry for the confusion.

73/jeff/ac0c
www.ac0c.com
alpha-charlie-zero-charlie

-----Original Message----- 
From: David Novoa, W4DN
Sent: Wednesday, September 12, 2012 12:16 PM
To: topband at contesting.com
Subject: Re: Topband: elevated radial symetry and layout

Fellows, I think that's an interesting question.
Please reply to Jeff's inquiry on the reflector, so all of us who are
interested in the subject can benefit from your advice.
TU es 73,
Dave, W4DN (Ex-KP4AM)


_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK

_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK