Helix antennas are directional antennas for circular polarization
mainly developed for satellite communications but just as well usable for terrestrial
operations. Due to physics based reasons the circular polarization shows significant
advantages when the received signal may consist of a mix of all kinds of polarizations due
to heavy reflections. As an example: If the phase of a received signal is perpendicular to
the antenna plane the resulting signal level can be up to 18 dB (3 S-levels) down compared
to a normal yagi! The right-hand circular polarization originates from a helix - the
antenna radiates into the direction of the helix. The reflector directs the
electromagnetic energy forward; to decrease the antenna's wind load the reflector is
perforated (many small holes). All antennas except the type Helix 70-2 are designed for
fore-mast installation. By means of power splitters the helix antennas can be combined to
form antenna groups of 2 or 4. The antennas have a standard N-connector and are made of
non- corrosive aluminum material with all nuts and bolts made of stainless steel.
 |
 |
 |
| Helix 70 |
Helix 70-2 |
Helix 23 |
 |
 |
 |
|
Helix 13 |
Helix 13-40 |
| |
Helix 70 |
Helix 70-2 |
Helix 23 |
Helix 23-2 |
Helix 23-4 |
Helix 13 |
NEW! Helix 13-40 |
| Frequency
Range |
430-440 |
430-440 |
1250-1300 |
1250-1300 |
1250-1300 |
2300-2450 |
2300-2450 |
MHz |
| Gain
(circular right hand) |
9.5 |
12.5 |
11 |
13 |
16 |
14 |
16 |
dBc |
| Turns |
7 |
14 |
10 |
20 |
40 |
21 |
40 |
| SWR |
1.5 |
1.5 |
1.5 |
1.5 |
1.5 |
1.5 |
1.5 |
| Power
Rating |
1000 |
1000 |
500 |
500 |
1000 |
500 |
500 |
Watt |
| Connector |
N-Connector |
N-Connector |
N-Connector |
N-Connector |
N-Connector |
N-Connector |
N-Connector |
| Mast
Diameter max. |
60 |
60 |
50 |
50 |
50 |
65 |
65 |
mm |
| Length |
1.5 |
2.9 |
0.6 |
1.4 |
0.6 |
0.8 |
1.25 |
m |
| Metal
Reflector Diameter |
45 |
45 |
22 |
22 |
60x60 |
10 |
10 |
cm |
| Weight |
2.5 |
4.5 |
1.0 |
1.4 |
2.2 |
0.7 |
1.1 |
Kg |
| Wind Load |
125 |
225 |
120 |
200 |
350 |
70 |
110 |
N |
| Material |
AlMgSi 0.5, Bolts
V2A |
| Gain
over cross dipole (dBc) |