w8io

The W8IO Antenna Site - 144-16V2 Yagi

(updated 27 Sep 2016)

This particular antenna design was inspired by Hartmut DG7YBN and he was inspired by Günter DL6WU and Brian K6STI. His designs blend extremely high antenna gain, high G/T (which means a low noise temperature) along with a broad gain and VSWR bandwidth. The DE design is also very easy to build and allows adjustment of VSWR without significantly affecting the gain and pattern performance. A broad VSWR and gain bandwidth is ideally suited for wet and snow/ice climates where accumulation of moisture on the elements can lower the antennas resonant frequency and degrade performance. In this design, I have adjusted the spacing and element lengths slightly to increase the Front/Rear to values over 30 dB in each plane. The E-plane achieves an amazing 31.78 dB Front/Rear (all lobes from -90 to -180 degrees) at 144.1 MHz. This allows the antenna to reject terrestrial noise sources to an extremely high degree for improved EME performance in noisy locations. Element diameters are common US sizes (1/4" and DE 3/8").

144-16V2 Performance

Electrical Performance:                     0.250" Element Diameter  (6.35 mm)         
Directive Gain (dBi)                                        16.95                                            
Power Gain (dBi)                                            16.84                                            
E-Plane F/R (dB)                                            31.78                                              
H-Plane F/R (dB)                                            30.15                                              
E-Plane 1st Sidelobe (dB)                              -18.8                                             
H-Plane 1st Sidelobe (dB)                             -16.1                                             
E-Plane Beamwidth (deg)                                28.0                                              
H-Plane Beamwidth (deg)                                29.0                                             
Max VSWR (144-146 MHz)                           1.5                                                
4 Bay G/T (dB) at 4.6m (E) x 4.4m (H)          -0.59                                        

Mechanical Performance:
Boom Length        32.3 feet        9.86 m        4.73 wavelength
Recommended Boom diameters: 1" to 1.5" either square or round (DX Engineering or On-Line Metals)
Recommended element insulators: Directive Systems
Recommended element sources: On-Line Metals, McMaster-Carr

144-16V2 NEC file  EZNEC file (1/4" elements)


144-16V2 Dimensions
Element Cum Spacing
(m)		 0.250" Element Diameter
Element Half-Lengths (m)
Dielectric Boom or NEC simulation		 0.188" Element Diameter
Element Half-Lengths (m)
Dielectric Boom or NEC simulation
Reflector 0 0.5095
Driven Element
(0.375" OD)		 0.286 0.4905
D1 0.421 0.482
D2 0.707 0.4775
D3 1.246 0.466
D4 1.886 0.4585
D5 2.628 0.451
D6 3.419 0.445
D7 4.239 0.439
D8 5.086 0.4345
D9 5.939 0.4315
D10 6.771 0.4245
D11 7.592 0.4315
D12 8.388 0.438
D13 9.160 0.434
D14 9.860 0.415



Driven Element details (in):
DE


Patterns:






Comments are welcome!

contact Roger: email to 

rgcox2 (at) gmail.com

Roger Cox - Spring Lake, MI