V Dipole antennas

[VU2TE]

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

[K0IZ]

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.

[WA9YSD]

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