K4MIA
Member
Posts: 7
|
 |
« on: March 25, 2010, 03:14:07 PM » |
|
Hi Guys,
I have started my phased vertical project. The 1st vertical is in. I have a dumb question about installing radials. Can I attached both verticals to the same radial. If I tie both verticals together with some common radials (ground shield to ground shield) or over lap radials touching will this screwup my pattern, directivity or cause other problems.
Tnx 73 Mike
|
|
|
|
|
Logged
|
|
|
|
W6OP
Member
Posts: 328
|
|
« Reply #1 on: March 25, 2010, 04:04:31 PM » |
|
Where the radials are going to overlap, run a wire perpendicular to the plane of the antennas (crossways) and bond both radial fields to that wire. Basically connect all overlapping radials together.
Pete W6OP
|
|
|
|
|
Logged
|
|
|
|
K4MIA
Member
Posts: 7
|
|
« Reply #2 on: March 27, 2010, 08:08:10 PM » |
|
Tnx for the information Pete.
73 Mike K4MIA
|
|
|
|
|
Logged
|
|
|
|
WX7G
Member
Posts: 4933
|
|
« Reply #3 on: March 27, 2010, 08:43:32 PM » |
|
Proof? Why connect the overlapping radials together?
|
|
|
|
|
Logged
|
|
|
|
VK7RJ
Member
Posts: 5
|
|
« Reply #4 on: March 30, 2010, 12:51:20 AM » |
|
In the AM broadcast world if they use a second vertical to adjust the pattern where the radials "overlap" they run a busbar at 90 deg and connect all the radials to that. but not any that wouldn't touch another one. if you have any questions about it i can draw a diagram of how one of the local stations is set up. i think i even have a few photos.
VK7RJ
|
|
|
|
|
Logged
|
|
|
|
WX7G
Member
Posts: 4933
|
|
« Reply #5 on: March 30, 2010, 06:47:25 AM » |
|
We still don't know if connecting the radials is a 'must have' or a 'nice to have.'
I'll analyze this using NEC-2.
|
|
|
|
|
Logged
|
|
|
|
W6OP
Member
Posts: 328
|
|
« Reply #6 on: March 30, 2010, 08:40:14 AM » |
|
It will be interesting what you find modeling it. I said to connect them because all my books on phased verticals show them that way. I don't recall that anyone has ever shown any data proving it is better. I would think the biggest reason may be it improves the radial field for each antenna, at least in one direction.
Pete W6OP
|
|
|
|
|
Logged
|
|
|
|
|
KL7AJ
|
|
« Reply #7 on: March 30, 2010, 12:29:09 PM » |
|
The reason for this in the broadcasting world is that the radial ends have high voltage on them...and depending on the phasing of the towers, it could be DIFFERENT high voltages on them. You don't want them arcing to each other under the ground!
Eric
|
|
|
|
|
Logged
|
|
|
|
VK7RJ
Member
Posts: 5
|
|
« Reply #8 on: April 01, 2010, 04:08:17 AM » |
|
yes well i guess there are alot of volts on the end of a antenna of a 50KW transmitter.
|
|
|
|
|
Logged
|
|
|
|
N4JTE
Member
Posts: 985
|
|
« Reply #9 on: April 01, 2010, 09:04:19 PM » |
|
What is your vertical layout, band, phasing, number of radials?
need more info to help.
|
|
|
|
|
Logged
|
|
|
|
|
