Re: Topband: elevated radial symetry and layout
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@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@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 ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
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@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
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
Topband: elevated radial symetry and layout
I’m cooking up my first 4-square using a set of elevated radials. Is there a consensus on what the optimal way of laying out the radial pattern is? If the radials are spread out on the 0/90/180/270 points, we have overlap between each of the radial center points (the 180 degree radial on the top vertical overlaps with the 0 degree radial on the bottom, for example). In the ON4UN book, a good diagram of the bonded and trimmed variety is shown for the ground mounted. But for elevated, he suggests alternating the radials on each vertical with a 45 degree rotation. Unfortunately his drawing is only for 2 verticals. If you expand his layout, all of the vertical radials are clear except for the pair which bisect the diagonal centerline and thus overlap. In addition, the center is where the control box is going to have to be as well - so that puts the radials with their attendant significant currents in close proximity to the phasing lines and box. In Rudy’s QEX he goes into the reduced sensitivity to symmetry associated of using 8-12 elevated radials per vertical. But for the more simple 4 per vertical case, I am looking for what the proper routing method should be to optimize the symmetry of the 4 square. Thanks! 73/jeff/ac0c www.ac0c.com alpha-charlie-zero-charlie ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
