Telrex 2mtr/8el stacked
Free Space Symmetric
144.20 MHz
16 6061-T6 wires, inches
r = 21.00
de = 19 ; guess of unmatched dipole
d1 = 18.25
d2 = 18.00
d3 = 17.25
d4 = 17.125
d5 = 17.375
d6 = 18.00
sp1 = 15.5
sp2 = 32
sp3 = 52
sp4 = 74
sp5 = 108
sp6 = 138
sp7 = 163
h = 0
hs = h + 10.5'
1 0 -r hs 0 r hs 0.25
1 sp1 -de hs sp1 de hs 0.5
1 sp2 -d1 hs sp2 d1 hs 0.25
1 sp3 -d2 hs sp3 d2 hs 0.25
1 sp4 -d3 hs sp4 d3 hs 0.25
1 sp5 -d4 hs sp5 d4 hs 0.25
1 sp6 -d5 hs sp6 d5 hs 0.25
1 sp7 -d6 hs sp7 d6 hs 0.25
1 0 -r h 0 r h 0.25
1 sp1 -de h sp1 de h 0.5
1 sp2 -d1 h sp2 d1 h 0.25
1 sp3 -d2 h sp3 d2 h 0.25
1 sp4 -d3 h sp4 d3 h 0.25
1 sp5 -d4 h sp5 d4 h 0.25
1 sp6 -d5 h sp6 d5 h 0.25
1 sp7 -d6 h sp7 d6 h 0.25
2 sources
Wire 2, center
Wire 10, center

12/2003 - installed on rooftop, 11' stack
8/2001 - Telrex antenna(s) from Stan
Hairpin match not simulated, dipole length guessed.
.5" overall element correction for thru-boom mounting (non-insulated)
All element dimensions shortened .25" except driven.
Actual element lengths:
r = 42.5
de = 16.5 * 2 with 2.3" gap between elements
d1 = 37
d2 = 36.5
d3 = 35
d4 = 34.75
d5 = 35.25
d6 = 36.5

For noninsulated through-the-boom mounting, measurements
by Guenter Hoch, DL6WU, have been curve-fitted by Ian White,
G3SEK, to yield the following boom-correction formula for Yagis:

C = 25.195B - 229B^2

C is the correction factor expressed as a fraction of
boom diameter B in wavelengths. B^2 means B-squared. For
example, a .01-wavelength diameter boom requires an element-
length correction of 23% of the boom diameter. The experimental
data underlying this formula were derived from booms with
diameters less than .055 wavelength. G3SEK indicates that
correction factors for insulated, through-the-boom mounting are
close to 50% of C.