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Re-scaled holl_ands Hi-VHF, 7-Element Folded Dipole Yagi to better cover the
Hi-Vhf band.

Good for channels 8-13.

Maybe channel 7, if it is a strong local station.

Frequency 209 mhz, has the highest gain at 12.07 db.


Yagi Gain:




Yagi Swr:





Here is the Nec code.

Code:
CM Hi-VHF, 7-Elem. Folded Dipole Yagi - Python Opt. - 4nec2 by holl_ands - 25Aug2011
CM Optimized via nikiml's v.6.5.2 Python Scripts.  SOURCE: Elem#2 middle segment.
CM All Cu O.D.=0.375".
CM Segments per AutoSegmenter.  Square 1.25-in WOOD Boom: no Boom Correction needed
CM Elements mount on TOP of boom.  Driven Element is 0.25-in higher due to insulation.
CM ALL MEASUREMENTS ARE IN INCHES.
CM Sweep ranges:
CM R0 = (174, 6, 8) with target levels (11.0, 11.0)
CM SWR target: 2.2
CM Target function: max(max_gain_diff, max_swr_diff)
CE
GW    1    15    0    -14.539963    0.6423625    0    14.5399574    0.6423625    0.19270875
GW    2    15    11.440229    -14.1678    0.8993075    11.440229    14.167803    0.8993075    0.1927088
GW    3    15    11.440229    -14.1678    -0.899308    11.440229    14.167803    -0.899308    0.1927088
GW    4    1    11.440229    14.167803    0.8993075    11.440229    14.167803    -0.899308    0.1927088
GW    5    1    11.440229    -14.1678    0.8993075    11.440229    -14.1678    -0.899308    0.1927088
GW    6    13    15.721886    -12.15225    0.6423625    15.721886    12.15225    0.6423625    0.1927088
GW    7    13    25.943222    -12.20232    0.6423625    25.943222    12.202318    0.6423625    0.1927088
GW    8    13    38.069535    -12.33978    0.6423625    38.069535    12.339778    0.6423625    0.1927088
GW    9    13    52.280043    -11.91101    0.6423625    52.280043    11.911009    0.6423625    0.1927088
GW    10    13    68.013114    -12.29802    0.6423625    68.013114    12.29802    0.6423625    0.1927088
GS    0    0    0.0254        ' All in in.
GE    0
EK
LD    5    0    0    0    5.8e7    0
EX    0    2    8    0    1    0
GN    -1
FR    0    1    0    0    198    0
RP 0 1 73 1510 90 0 1 5 0 0

Have fun building antennas.
 

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Re-scaled holl_ands Hi-VHF, 7-Element Folded Dipole Yagi to better cover the
Hi-Vhf band.
Be careful with how you use commonly accepted terms, to help reduce confusion. "Re-scaled" would indicate that you changed all dimensions, by the same "scale" factor or multiplier. Your design is more of a redesign.
Your design works very well near the center of the frequency band. It does not covers the lower end of the band, as well as the original. I don't know if I'd consider it a good design, if your trying to cover the entire band. It would work well for someone just wanting to get a single channel near 198mhz.
One of the unique features, of a well designed Yagi antenna, is it's high front to back ratio. This tells you how much signal will be received from the front, verses how much signal, and more important noise, will be rejected from the back. Your redesign actually has higher gain from the back, from 174mhz to 177mhz, than from the front. This will pick up a lot of unwanted signal and noise from the back. It may not matter in some locations, but may reduce the usefulness of the antenna, for most applications. Most people chose a well designed Yagi, because it limits the reception of unwanted signal and noise from most directions, with very good gain from the front. Overall I think the original design is better suited for it's intended purpose, of covering the entire HiVHF band, with good directionality.
 
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