Original article from: Wayne Sarosi
Reposted by Rob Dennis,Moderator HAM_TECH,for use of the FIDO HAM_TECH echo.
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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
-WS
--- GoldED 2.42.G1219
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* Origin: VE3SJN....Moderator....HAM_TECH (1:163/506.4)
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