| Top view of a five band classic hexagonal beam antenna showing wires only with no spreaders or other supporting structure. Diameter is 19 feet |
| Top view of a five band G3TXQ hexagonal beam antenna showing wires only with no spreaders or other supporting structure. Diameter is 22 feet |
The forward gain of the G3TXQ hexagonal beam is slightly better than the classic design.
The front/back gain ratio of the G3TXQ hexagonal beam is dramatically better than the
classic design. This means that unwanted signals coming into the transceiver from the
back of the beam will be much less than with the classic hex beam.
classic design. This means that unwanted signals coming into the transceiver from the
back of the beam will be much less than with the classic hex beam.
Azimuthal radiation patterns for the classic hexagonal beam and for the G3TXQ
hexagonal beam. Note the slightly superior forward gain and the significantly superior
front/back performance of the G3TXQ hexagonal beam.
hexagonal beam. Note the slightly superior forward gain and the significantly superior
front/back performance of the G3TXQ hexagonal beam.
| Classic |
Construction of the G3TXQ broad band hexagonal beam is easier than the classic heagonal beam.
|
Station in Iceland on 20 Meters
Station in USA on 17 Meters
On air recordings to demonstrate front to back performance of
the broad band hexagonal beam.
These audio clips were recorded by G3TXQ in January 2008
from switching back and forth every 3 - 5 seconds between one
hexagonal beam and another aimed 180 degrees to the rear.
the broad band hexagonal beam.
These audio clips were recorded by G3TXQ in January 2008
from switching back and forth every 3 - 5 seconds between one
hexagonal beam and another aimed 180 degrees to the rear.
| G3TXQ |
Data for five band beams on 20 meters at 30 feet above good ground. Azimuthal patterns at
29 degrees elevation. SWR for 50 ohm feed.
29 degrees elevation. SWR for 50 ohm feed.
Note that the peak of front/back performance of the classic
version occurs at 14.05 mHz whereas the SWR at this same
frequency is about 2.2:1, a sub-optimal point on the SWR curve.
What this means is that it is necessary to compromise between
optimal SWR and best F/B with the classic design. On the other
hand, with the broadband version, the front/back performance
peaks at the lowest SWR with the result that there is no need to
compromise between these two major goals in beam
perfomance.
version occurs at 14.05 mHz whereas the SWR at this same
frequency is about 2.2:1, a sub-optimal point on the SWR curve.
What this means is that it is necessary to compromise between
optimal SWR and best F/B with the classic design. On the other
hand, with the broadband version, the front/back performance
peaks at the lowest SWR with the result that there is no need to
compromise between these two major goals in beam
perfomance.
The SWR of the G3TXQ hexagonal beam is dramatically better on the low end of the band
making it easier to couple the transceiver to the antenna for maximal power transfer.
making it easier to couple the transceiver to the antenna for maximal power transfer.
Hexagonal Beam by K4KIO
Building the G3TXQ Broad Band Hexagonal Beam
The New G3TXQ Broad Band Hexagonal Beam vs the Classic hexagonal beam
The original or classic hexagonal beam is the configuration of the Hex-beam manufactured by Traffie Technologies
and copied by many homebrewers. The classic hexagonal beam is a proven winner among those who have built
one. However, the classic beam has a significant shortcoming that is a result of its compressed configuration. It is
rather narrow banded. In fact, if you design your classic hexagonal beam for use on the SSB portion of the larger
bands such as 20 or 15 meters it will perform quite well. But you will find that the front to back performance on the
CW end of the band is quite mediocre if not downright unacceptable. You can adjust the wires for resonance at the
middle of the band but then it will be only average in performance on both the SSB and CW sub bands.
In November 2007, Steve Hunt, G3TXQ, developed a major improvement in the classic hexagonal beam to
overcome these bandwidth limitations. The new G3TXQ hexagonal beam is much broader in its performance and
as a result will deliver quite good front to back performance as well as low SWR over the entire range of
frequencies of the larger bands. Below are charts that illustrate the differences in the classic and broadband
hexagonal beams on 20 meters. The only penalty to be paid for this improved performance is a slightly larger
diameter of the broad band. The five band classic hexagonal beam for 10, 12, 15, 17, 20 meters is about 19 feet in
diameter; the broadband is 22 feet.
This minor difference in size for such a major improvement in performance causes me to recommend the G3TXQ
hexagonal beam over the classic. I have modeled both, I have built both, I have tested both and I have used both.
And I am convinced that the G3TXQ broad band beam is better.
At the urging of the late L.B. Cebik, W4RNL, Steve recently authored an article featuring the broad band hexagonal
beam in the December 2007 edition of the ham radio on line antenna magazine, AntenneX. Below is a comparison
of the classic and the broad band hexagonal beams.
The original or classic hexagonal beam is the configuration of the Hex-beam manufactured by Traffie Technologies
and copied by many homebrewers. The classic hexagonal beam is a proven winner among those who have built
one. However, the classic beam has a significant shortcoming that is a result of its compressed configuration. It is
rather narrow banded. In fact, if you design your classic hexagonal beam for use on the SSB portion of the larger
bands such as 20 or 15 meters it will perform quite well. But you will find that the front to back performance on the
CW end of the band is quite mediocre if not downright unacceptable. You can adjust the wires for resonance at the
middle of the band but then it will be only average in performance on both the SSB and CW sub bands.
In November 2007, Steve Hunt, G3TXQ, developed a major improvement in the classic hexagonal beam to
overcome these bandwidth limitations. The new G3TXQ hexagonal beam is much broader in its performance and
as a result will deliver quite good front to back performance as well as low SWR over the entire range of
frequencies of the larger bands. Below are charts that illustrate the differences in the classic and broadband
hexagonal beams on 20 meters. The only penalty to be paid for this improved performance is a slightly larger
diameter of the broad band. The five band classic hexagonal beam for 10, 12, 15, 17, 20 meters is about 19 feet in
diameter; the broadband is 22 feet.
This minor difference in size for such a major improvement in performance causes me to recommend the G3TXQ
hexagonal beam over the classic. I have modeled both, I have built both, I have tested both and I have used both.
And I am convinced that the G3TXQ broad band beam is better.
At the urging of the late L.B. Cebik, W4RNL, Steve recently authored an article featuring the broad band hexagonal
beam in the December 2007 edition of the ham radio on line antenna magazine, AntenneX. Below is a comparison
of the classic and the broad band hexagonal beams.
Available for purchase
| Site publication date 12/2007 Page revision date 7/2009 Copyright 2009 |