SL FM Yagi KUSC-7el
Free Space Symmetric
91.500 MHz
16 6061-T6 wires, inches
rfs = -18		; org space = -18.0"
des = .001		; org space = .000"
drs1 = 8		; org space = 8.0"  
drs2 = 47		; opr space = 47.0" 	
drs3 = 71		; add space = 71.0"
drs4 = 89		; add space = 89.0"
drs5 = 132		; add space = 132"

dia = .392		; 25/64" for Drvn EL
dia1 = .376		; 3/8" for Ref + D2,3,4,5 
dia2 = .438		; 14/32" for D1  

rfl = 31.5		; org length = 31.50"  
dr1 = 29		; org length = 29.0" 
dr2 = 28.75		; org length = 28.75" 
dr3 = 28.75		; org length = 28.75"
dr4 = 28.5		; org length = 28.5"
dr5 = 28.5		; org length = 28.5" 

len = 27.75		; drv el half-length; org length = 27.75"
sp = 1.824		; drv el upside spacing: c/b = 1.824"
nsp = -1.46		; drv el downside spacing: c/b = -1.46"

 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    dia1
 1   rfs     0.0   0    rfs     rfl    0    dia1 
 1   drs1   -dr1   0    drs1    0.0    0    dia2
 1   drs1    0.0   0    drs1    dr1    0    dia2
 1   drs2   -dr2   0    drs2    0.0    0    dia1
 1   drs2    0.0   0    drs2    dr2    0    dia1
 1   drs3   -dr3   0    drs3    0.0    0    dia1
 1   drs3    0.0   0    drs3    dr3    0    dia1
 1   drs4   -dr4   0    drs4    0.0    0    dia1
 1   drs4    0.0   0    drs4    dr4    0    dia1
 1   drs5   -dr5   0    drs5    0.0    0    dia1
 1   drs5    0.0   0    drs5    dr5    0    dia1
 1 source
 Wire 1, center

 This antenna was modeled starting from the stock Stellar Labs 4el FM antenna. 
 Five (5) dir elements were added and the boom streched to 12' 6".
 An AO analysis shows;
  12.3 db F/G 
  11.2 db F/B
  300 ohm feed impedance- swr due to match; 308 + j 6 
  SWR = 1.04:1

 To receive the FM station from Los Angeles @ 91.5 Mhz - KUSC FM 

 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 1100 ohms) at the feed 
 point to further attenuate the common mode signal.  
 
 Where I live F/G is more important than F/B ratio b/c of distance to KUSC's
 xmitter site . . .109 miles. Need all the F/G that I can get!