Stellar Labs 30-2460

The Stellar Labs 30-2460 is a four-element Yagi with folded dipole and integral 75:300Ω balun. The boom length is 1.63 m (64″). The red dot marks the feedpoint.

Modeling Results

I modeled the antenna with the AO 9.61 Antenna Optimizer. Calculated performance is for 28 analysis segments per conductor halfwave. Forward gain includes mismatch and conductor losses. F/R is the ratio of forward power to that of the worst backlobe in the rear half-plane.

Frequency  Impedance    SWR   Mismatch  Conductor   Forward    F/R   
   MHz        ohms             Loss dB   Loss dB   Gain dBd     dB   
    88     131 - j85    2.52     0.90      0.01      4.51      8.29  
    89     147 - j53    2.12     0.60      0.01      4.84     10.34  
    90     164 - j26    1.84     0.40      0.01      4.99     12.13  
    91     180 - j1     1.67     0.28      0.01      5.04     13.35  
    92     195 + j22    1.56     0.21      0.01      5.04     13.91  
    93     208 + j43    1.50     0.17      0.01      5.02     13.89  
    94     221 + j64    1.48     0.17      0.01      4.99     13.49  
    95     234 + j84    1.49     0.17      0.01      4.95     12.93  
    96     247 + j105   1.54     0.20      0.01      4.92     12.33  
    97     262 + j125   1.59     0.23      0.01      4.88     11.72  
    98     276 + j146   1.67     0.28      0.01      4.85     11.16  
    99     291 + j169   1.76     0.34      0.01      4.81     10.65  
   100     308 + j191   1.86     0.41      0.01      4.78     10.17  
   101     327 + j215   1.97     0.49      0.01      4.74      9.74  
   102     349 + j239   2.09     0.58      0.01      4.70      9.33  
   103     376 + j262   2.20     0.66      0.01      4.66      8.96  
   104     405 + j285   2.33     0.75      0.01      4.62      8.62  
   105     439 + j306   2.45     0.84      0.01      4.59      8.32  
   106     479 + j324   2.56     0.93      0.01      4.55      8.06  
   107     524 + j336   2.66     1.00      0.01      4.52      7.85  
   108     573 + j339   2.73     1.06      0.01      4.51      7.71  

Antenna File

Stellar Labs 4-Element Yagi
Free Space Symmetric
98 MHz
7 6063-T832 wires, mm
ab = 46			; DE distance above boom
bb = 37			; DE distance below boom
dep = 629		; element positions
d1p = 1113
d2p = 1630
r = 808			; element half-lengths
de = 705
d1 = 589
d2 = 589
1     0   -r    0      0    r    0    10
1   dep  -de  -bb    dep   de  -bb    10
1   dep  -de   ab    dep   de   ab    10
1   dep  -de   ab    dep  -de  -bb    10
1   dep   de   ab    dep   de  -bb    10
1   d1p  -d1    0    d1p   d1    0    10
1   d2p  -d2    0    d2p   d2    0    10
1 source
Wire 2, center

Modified Antenna

You can improve performance by adding an element between the driven element and first director. Element diameter is ⅜″ and length is 50″. Place it 10″ forward of the driven element.


July 11, 201688108 MHz