NEW UHF Free-Form 4-Bay + FlatScreenRefl

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NEW UHF Free-Form 4-Bay + FlatScreenRefl

NEW-UHF [470-608 MHz] Free-Form 4-Bay (NU-FF4) Bowtie Antennas with Flat Screen Grid Reflector
analyzed using 4nec2. Dimensions were Optimized using nikiml's Python Scripts, including
Angle of Reflector's outer "wings"....which was nearly ZERO...essentially FLAT.

Dimensions for VARIABLE DOUBLE ANGLE REFLECTOR are 48 H x 36-in W (unfolded),
with 2x2-in GRID assumed for this model to speed up Optimization Execution Time and stay
within 4nec2 and NEC2 parameter constraints, incl. Total Number of Segments.
If higher F/B and/or F/R Ratios are desired, reduce Grid Vertical Spacing to 1-in or 0.5-in.

UHF Raw Gain = 15.3 to 16.2 dBi, F/B & F/R Ratio Min = 16.6 dB and SWR (300-ohms) under 2.2.
Hi-VHF Raw Gain = 8.8 to 8.9 dBi, F/B & F/R Ratio Min = 12.0 dB and SWR (300-ohms) = 33 to 22 [Excessive].

Compared to Old UHF Band FF4, we see Gain of 0.7 dB on 470 MHz and 1.1 dB on 608 MHz:
UHF Raw Gain = 14.6 (470 MHz) to 15.0 (608 MHz), 16.2 (674 MHz) peaking at 17.1 dBi (698 MHz)
UHF F/B & F/R Ratio Min = 14.8 dB [GOOD] and SWR (300-ohms) under 2.1.
Hi-VHF Raw Gain = 10.8 to 8.3 dBi, F/B & F/R Ratio Min = 10.9 dB [FAIR] and SWR (300-ohms) = 34 to 23 (Excessive).
https://imageevent.com/holl_ands/multibay/4bayrefl/uhffreeform4baydblanglreflopt

DIMENSION STATEMENTS: [May Round to nearest 1/4-inch]
' Radius (in inches) of BOWTIE elements:
SY Rbow=0.051 [AWG10]
' Radius (in inches) of FEEDLINE wires:
SY Rfeed=0.051 [AWG10]
' Separation at Crossover:
SY Hop=1.0
' Conductivity (Copper=3.0e7, Alum=2.0e7, StainlessSteel=1.67e7):
SY Cond=3e+07
' Distance between the centers of the two INNER bowties:
SY ZBowII=14.72
' From center of INNER bowtie to center of OUTER bowtie:
SY ZBowOI=12.10
' INNER Bow Whisker Length (lose some in bend):
SY BowLeni=13.13
' OUTER Bow Whisker Length (lose some in bend):
SY BowLeno=8.53
' INNER Bow Forward Sweep distance at tip of the whisker:
SY BowSwpi=2.51
' OUTER Bow Forward Sweep distance at tip of the whisker:
SY BowSwpo=1.46
' INNER Bow Tine Separation:
SY TineSepi=7.62
' OUTER Bow Tine Separation:
SY TineSepo=3.36
' Separation between two FEEDLINE wires:
SY FeedSep=3.48
' From center of Feedline Cross-Over to center of OUTER Bowtie:
SY ZCross=3.045
' Reflector to Bowtie Separation:
SY RS=3.69
' Bend Sweep (Forward in inches:
SY Bend=0.19 [Essentially Zero]

UPDATE (29Nov2017): Uploaded Images with improved viewability (esp. Thumbnails)
with NO Change to content.

UPDATE (7May2019): Added comparison to Old UHF Band FF4.

UPDATE (17Aug2019): Added Dimension Statements.

Date(s): 19 Jul 2017. Album by holl_ands. 1 - 16 of 16 Total. 7041 Visits.

enlarge 214KB, 655x1024 1 NEW-UHF Free-Form 4-Bay + ScreenRefl 3D View	enlarge 341KB, 804x1024 2 NEW-UHF Free-Form 4-Bay + ScreenRefl Front View [1 Large Square = 5-inches]	enlarge 119KB, 313x1024 3 NEW-UHF Free-Form 4-Bay + ScreenRefl Top View [1 Large Square = 5-inches] "[1 Large Square = 2.5-inches]" View Comments...
enlarge 226KB, 1024x649 4 NEW-UHF Free-Form 4-Bay + ScreenRefl UHF Raw Gain = 15.3 to 16.2 dBi UHF F/B & F/R Ratio Minimum = 16.6 dB	enlarge 199KB, 1024x649 5 NEW-UHF Free-Form 4-Bay + ScreenRefl UHF SWR (300-ohms) Under 2.2	enlarge 241KB, 1024x649 6 NEW-UHF Free-Form 4-Bay + ScreenRefl UHF Impedance
enlarge 340KB, 1024x1024 7 NEW-UHF Free-Form 4-Bay + ScreenRefl Azimuthal Pattern at 470 MHz	enlarge 338KB, 1024x1024 8 NEW-UHF Free-Form 4-Bay + ScreenRefl Azimuthal Pattern at 530 MHz	enlarge 341KB, 1024x1024 9 NEW-UHF Free-Form 4-Bay + ScreenRefl Azimuthal Pattern at 590 MHz
enlarge 364KB, 1024x1024 10 NEW-UHF Free-Form 4-Bay + ScreenRefl Azimuthal Pattern at 608 MHz	enlarge 343KB, 1024x1024 11 NEW-UHF Free-Form 4-Bay + ScreenRefl Azimuthal Pattern at 650 MHz	enlarge 340KB, 1024x1024 12 NEW-UHF Free-Form 4-Bay + ScreenRefl Azimuthal Pattern at 698 MHz
enlarge 129KB, 407x1024 13 NEW-UHF Free-Form 4-Bay + ScreenRefl Side View [1 Large Square = 5-inches]	enlarge 118KB, 791x1024 14 NEW-UHF Free-Form 4-Bay + ScreenRefl 4nec2 File includes all Dimensions	enlarge 28KB, 791x1024 15 NEW-UHF Free-Form 4-Bay + ScreenRefl EVAL Summary of Performance Text File
enlarge 100KB, 791x1024 16 NEW-UHF Free-Form 4-Bay + ScreenRefl EVAL *.html Performance Summary

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