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 9.67 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      130-j94     2.58     0.94      0.01      4.47       8.33
    89      146-j62     2.17     0.63      0.01      4.81      10.38
    90      162-j34     1.88     0.43      0.01      4.98      12.17
    91      178-j10     1.69     0.30      0.01      5.04      13.38
    92      192+j13     1.57     0.22      0.01      5.05      13.94
    93      205+j34     1.50     0.18      0.01      5.04      13.90
    94      218+j55     1.47     0.16      0.01      5.01      13.50
    95      230+j75     1.47     0.16      0.01      4.98      12.93
    96      242+j96     1.51     0.18      0.01      4.95      12.32
    97      256+j115    1.55     0.21      0.01      4.92      11.71
    98      270+j137    1.63     0.26      0.01      4.89      11.15
    99      285+j159    1.72     0.31      0.01      4.86      10.64
   100      301+j181    1.81     0.38      0.01      4.83      10.16
   101      319+j205    1.92     0.45      0.01      4.79       9.72
   102      340+j228    2.03     0.54      0.01      4.76       9.32
   103      366+j251    2.15     0.62      0.01      4.72       8.94
   104      394+j274    2.27     0.71      0.01      4.68       8.61
   105      426+j295    2.39     0.80      0.01      4.65       8.30
   106      464+j313    2.50     0.88      0.01      4.61       8.05
   107      507+j326    2.59     0.95      0.01      4.58       7.84
   108      554+j329    2.67     1.00      0.01      4.58       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 forward gain by extending the boom and adding an element. Use one 96″ length of 6063-T5 aluminum angle. Cut a 49″ piece for the element. Use the remainder, doubled up side by side, to support it 22″ in front of the last director.

Joe Comer, AD3P, in Severna Park, Maryland, modified his antenna. The modification improved reception of a favorite but weak station at the low end of the band.


October 14, 202088108 MHz