LPA for 67cm 

USE: 67cm amateur band, 442 to 450 MHz
Note: See the ARRL Antenna Handbook for details

Tau = 0.98
Sigma = 0.18714
B = 1.0181
COT Alpha = 37.428 
Bar = 1.2153
Bs = 1.2373
Lambda max = 2.226-ft
Lb = 4.3-ft
N=12
Zt=3.339

Elements in inches
    L1 = 6.679        Cut these as close as possible.
    L2 = 6.545        Diameter is 1/4 inch
    L3 = 6.414
    L4 = 6.286
    L5 = 6.160
    L6 = 6.037
    L7 = 5.916
    L8 = 5.798
    L9 = 5.682
   L10 = 5.568
   L11 = 5.456
   L12 = 5.347

  d1,2 = 5.015         Place elements as close as possible
  d2,3 = 4.915         using these figures. Conversion to mm
  d3,4 = 4.817         may help.
  d4,5 = 4.721
  d5,6 = 4.627
  d6,7 = 4.534
  d7,8 = 4.443
  d8,9 = 4.354
 d9,10 = 4.267
d10,11 = 4.182
d11,12 = 4.098

Gain = 11.0 dBi