Call Search
     

New to Ham Radio?
My Profile

Community
Articles
Forums
News
Reviews
Friends Remembered
Strays
Survey Question

Operating
Contesting
DX Cluster Spots
Propagation

Resources
Calendar
Classifieds
Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement
About eHam.net

   Home   Help Search  
Pages: [1]   Go Down
  Print  
Author Topic: V Dipole antennas  (Read 842 times)
VU2TE
Member

Posts: 3




Ignore
« on: March 04, 2012, 05:38:27 AM »

Recently I worked with vertical V dipole.  On 14 I could get an SWR of 14.005=1:1.3 and 14.345=1:1.1 an on 21 I got 21.005=1:2.5 and on 21.400=1:2.8.  Both the antennas are mounted on same boom with a gap of just 1 feet.  Now When I increase the length I am not able to reduce the SWR and its not tuning to the lower end. Now I want to experiment with the 28 element also on the same boom.  I can switch the antennas individual as well as interconnect all the and bands together and use common coax.  Can any one comment and modification on this setup and ways to improve the performance.  the idea to go for a Vertical V is its added advantage of the height.
Mailing to unnitharakkal@gmail.com will be helpful
So 73s 

Unni
VU2TE
Logged
K0IZ
Member

Posts: 737




Ignore
« Reply #1 on: March 04, 2012, 07:21:14 AM »

Rotating one pair aroung the center support would help decouple wires.  IE, if one pair is north/south, least coupling of a second pair would be oriented east/west.  For three pairs, orienting 60 degrees apart would work.  Disadvantage is that radiation patterns would also change due to rotation.   More spacing than one ft would also help.  You could also create a trap 20M dipole with 15 and 10M traps so that there is only one pair of wires. I would think that would work at least as well as separate pairs.    John.
Logged
WA9YSD
Member

Posts: 138




Ignore
« Reply #2 on: March 06, 2012, 08:34:07 AM »

Or try a 3 foot separation. If your going to feed both with the same coax make sure you use two pieces are identical and the same length, then joint the two together.  Use at least 50 feet for each.

What bands for each antenna?

Jim K9TF
« Last Edit: March 06, 2012, 08:39:33 AM by WA9YSD » Logged
Pages: [1]   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.11 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!