HF ten elements log-periodic array
Spacing d(n-1),n
Shortening factor
t = d(n-1),n / d(n-2),(n-1)Element length L
Wavelength
l = 2.LSpacing factor
s = d(n-1),n / 2.L(n-1)
Lengths are in mm
Element N. |
Element spacing |
t |
Element length |
l |
s |
Region gain (dbi) |
1 |
1174 |
0.8 |
8300 |
16600 |
0.070 |
6.5 - 7.0 |
2 |
939 |
0.8 |
6800 |
13600 |
0.069 |
6.5 - 7.0 |
3 |
751 |
0.9 |
6200 |
12400 |
0.060 |
6.5 - 7.0 |
4 |
675 |
0.9 |
6000 |
12000 |
0.056 |
6.5 - 7.0 |
5 |
608 |
0.9 |
4900 |
9800 |
0.062 |
8.5 |
6 |
547 |
0.9 |
3800 |
7600 |
0.071 |
8.5 |
7 |
492 |
0.9 |
3000 |
6000 |
0.082 |
8.5 |
8 |
442 |
0.9 |
2200 |
4400 |
0.100 |
8.5 |
9 |
n.a. |
0.9 |
n.a. |
n.a. |
n.a. |
n.a. |
10 |
n.a. |
0.9 |
n.a. |
n.a. |
n.a. |
n.a. |
Hardware : three pieces aluminum boom 6 m long, 0,5 m aluminum support, 1,2 m plastic support, 6 m plastic support, plus perimeter nylon rope.
Balun -
various types tried :(the last two baluns weren't of good feature ...)