Here are two yagis for 6m, one 1 wavelength long with a gain of 9.5dBd, and the other a 2.1wl model with a gain of 11.8dBd.
The design rules follow the proven method used for the 70cm OPT yagis. Solutions for element lengths and distances have to satisfy a criterion based on an optimum current slope and constant phase delay in the array of parasitic elements. If a solution satisfies this criterion, high gain per boomlength together with an excellent pattern can be expected.
Another constraint in the development of these Yagis was the requirement for 50 ohm input impedance. This allows simple feed structures like a folded dipole, which is electrically efficient and mechanically rugged.
During the final verification with NEC-II software it was found that these antennas have excellent stacking capability, with high stacking gains in excess of 5.8dB (2x) and minimum mutual detuning.
If properly built, these Yagis are excellent performers. They are cheap to build, and can be made from easily available materials.
Model, elements
|
Length | Gain [dBd] |
Front/ |
Beamwidth |
Stacking 2x2 | ||||
[m] |
[wl] |
E [deg] |
H [deg] |
E [m] |
H [m] |
Gain [dB] |
|||
BV6-1.0 |
5.850 | 1.0 | 9.40 | >19 | 45.6 | 54.0 | 7.7 | 6.6 | 5.9 |
BV6-2.1 10 |
12.90 | 2.1 | 11.90 | >25 | 36 | 40 | 9.4 | 8.6 | 5.9 |
These lengths are correct.
Element |
Position [mm] |
Boom diam [mm] |
Length [mm] |
R | 0 | 30 | 2966 |
DE | 922 | 30 | 2850 |
D1 | 1232 | 30 | 2734 |
D2 | 2411 | 30 | 2734 |
D3 | 4329 | 30 | 2702 |
D4 | 5850 | 30 | 2670 |
These lengths are correct.
Element |
Position [mm] |
Boom diam [mm] |
Length [mm] |
R | 0 | 30 | 2924 |
DE | 1209 | 30 | 2844 |
D1 | 1706 | 30 | 2724 |
D2 | 2712 | 35 | 2705 |
D3 | 4012 | 40 | 2686 |
D4 | 5536 | 40 | 2656 |
D5 | 7222 | 40 | 2636 |
D6 | 9040 | 40 | 2616 |
D7 | 10970 | 35 | 2595 |
D8 | 12900 | 30 | 2584 |