This chapter is
called beams because it will handle all antennas
wich are capable of producing a beam with the radiation pattern. Just
think of a beam as a flashlight where you point the flashlight. There
is light. With a beam antenna it is almost the same.
The patterns are for receiving aswell as transmitting....again...in the
antenna pattern there is no difference betweeen those looked at gain or
Looking at Front to back (especially with the high numebers) for
any figure above 30 dB you can not forget that this is at its highest
point 100khz besides the design frequencie the FB maybe dropped 10 dB.
If you want to know more about a design let me know through email .
With this diagram you can
see what your antenna system is producing when looked at the gain.
THE BELOW DESIGNS ARE DESIGNED WITH THE COMPUTER PROGRAM EZNEC,
5 different designs are tested. I could not find any proof that figures
were not real and the antennas were running as expected....GREAT!
For the future I hope to test all models, but as always time is
limited. Please read the other chapters to understand more about
beamwith, gain, front to back etc.
2 elements yagi 5 elements Yagi 6 elements Yagi
3 elements Yagi 4 elements Yagi 7 elements yagi
2 elements Quad 4 elements Quad 6 elements Quad
3 elements Quad 5 elements Quad 7 elements Quad
Yagi Yagi versus Quad
This diagram is what you could expect from your antenna, not what the
manufacturer is telling you!
When compared the below diagram to the diagram in chapter
manufactureres please NOTICE that the last mentioned is in dBI in stead of
the below dBD (so +2,14dB).
The above diagram (gain versus boomlenght) you will find figures based on real life measurements and
Figures in real live could difference with what this diagram is
telling, but the bounderies are within a single dB!
Remember it is NOT the number of elements on a Boom that makes the gain.
For its biggest part gain comes from BoomLENGHT!