To
All
Further to my
report by e-mail of 15 Sept. 1919 hrs I have also simulated by means of a
computer program top loads consisting of multiple parallel wires with spacings
of 0.5; 1.0; 1.5 and 2.0 m. All wires are of 1.5 mm copper (16
SWG).
The vertical
radiator is again 10 m long and the parallel top loading wires are horizontal
and 20 m long (inverted L antenna). The first report shows that the
characteristics of T- and inverted L-antennas with horizontal tops of the same
size are almost identical. So it seems reasonable to assume that the results
given in this report for 20 m long multiple parallel wires as top load are
applicable to both inverted L and T-antennas.
Finally the influence of increasing the
height of the antenna from 10 to 15 and 20 metres has been
investigated.
Number
of
Spacing between
Rs
C
top load
wires between wires
(m) milli-ohm
pF
1
-
22
176
2
0.5
24.9
236
2
1.0
25.2
247
2
1.5
25.5
255
2
2.0
25.7
261
3
0.5
26.1
280
3
1.0
26.8
304
3
1.5
27.1
321
3
2.0
27.3
335
4
0.5
27.1
316
4
1.0
27.6
353
4
1.5
28.0
381
4
2.0
28.2
403
One horizontal top load wire of 20
m
Height (m)
of
Rs
C
vertical radiator
milli-ohm pF
10
22
176
15
43.7
200
20
70.7
225
Four
horizontal parallel top load wires of 20 m long and 2 m
spacing
10
28.2
403
15
59.3
411
20
99
427
73, Dick, PA0SE
D.W. Rollema
V.d. Marckstraat 5
2352 RA Leiderdorp
Tel. +31 71 589 27 34