Stellar Labs FM Yagi -stock
Free Space Symmetric
98.000 MHz
10 6061-T6 wires, inches
rfs = -24.75
des = 0
drs1 = 19.063
drs2 = 39.438
dia = .392
rfl = 31.813
dr1 = 23.188
dr2 = 23.188

len = 27.75		; dr el half-length
sp = 1.824		; dr el upside dipole spacing	
nsp = -1.46		; dr el downside dipole spacing 

 1   0      -len   nsp   0       len   nsp    dia
 1   0      -len   sp    0       len    sp    dia
 1   0      -len   sp    0      -len   nsp    dia
 1   0       len   sp    0       len   nsp    dia

 1   rfs    -rfl   0    rfs     0.0    0    dia
 1   rfs     0.0   0    rfs     rfl    0    dia 
 1   drs1   -dr1   0    drs1    0.0    0    dia
 1   drs1    0.0   0    drs1    dr1    0    dia 
 1   drs2   -dr2   0    drs2    0.0    0    dia
 1   drs2    0.0   0    drs2    dr2    0    dia 
 1 source
 Wire 1, center

 This antenna was modeled from visual measurements of the Stellar Labs 4el FM 
 Antenna as delivered @ 98.0Mhz. AO analysis;
   7.3db F/G 
  11.0db F/B
  300 ohm feed impedance - 283 + j144 makes 
  SWR > 1.64:1.0

 In order to receive a mid-band FM station, it's is not quite what I would 
 like so it needs a bit of optimization. The elements lengths Ref, Dir 1,2 
 should be shorten and spacings changed to optimize for operaiton at 98Mhz. 

 The antenna has a 300 to 75 stripline transformer built into the feed point
 making the transmission line (RG-6) a better way to send the signal to my
 FM tuner. Add three (3) ferrite line chokes (apx 1000 ohms) at the feed point 
 to further attenuate the common mode signal.