Grazie per i vari consigli, penso che per il momento monterò solo la tonna 9
elementi VHF, con un mast in acciaio lungo 40 cm, diametro 4 cm, spessore 2
mm ed in seguito provvederò a questa benedetta gabbia.
Riporto parte delle istruzioni del manualetto per il calcolo :
Pole-Mounted Antennas
Mounting of the rotator on a pole or mast results in a significant de-rating
of the size of the antenna
which can be mounted, due to the tremendous bending forces applied to the
rotator's clamps. For
pole mounting, the attached antenna must have a net mounted weight (combined
weight of antenna
plus mast) of 10 kg or less, and the product of multiplying the [Antenna
Wind Load Area (in m2)] by the [Height of the Antenna Mast (in m)] must be
0.25 or less.
[Antenna Weight] + [Mast Weight] <= 10 kg.
[Antenna Wind Load Area] x [Height of Antenna Mast]<= 0.25
Refer to the antenna manufacturer's specification sheet for determining the
weight and the surface
area of the proposed antenna.
ESEMPIO
For a 50 MHz 5-element antenna of surface area of 0.3 m2, the above
specifications for pole mounting will be met if the antenna is mounted on a
mast
not longer than 0.8 m (0.3 x 0.8 = 0.24 <0.25), and if the mast weight plus
the
antenna weight is less than 10 kg. However, if the mast is 1 meter long, the
specification
will be exceeded (0.3 x 1 = 0.3 >0.25).
Quindi vedendo le caratteristiche della tonna 9 elementi:
Mass = 3 Kg.
Effective wind load horizontal polarization = 0,10 m2
Effective wind load vertical polarization = 0,15 m2
Peso della 9 elementi 3 kg.+ il tronchetto di 40 cm del mast non supero di
certo i 10kg.
Facendo il calcolo per la polarizzazione orizzontale (0,10 x 0,40) = 0,04
molto minore di 0,25
Credo che si può montare tranquillamente.
Riporto le caratteristiche del rotore G-450
Rotation Torque = 600 kgf-cm (43 ft-lbs.)
Braking Torque = 3000 kgf-cm (217 ft-lbs.)
Maximum Vertical load Continuous load = 100 kg or less (Instantaneous load
300 kg)
Mast Outside Diameter = D32 to D63 (center protrudes by D48 to D52)
Rotation Range = 450°
360° Rotation Time = 63 seconds at 50 Hz, 51 seconds at 60 Hz
Braking Type = Mechanical stopper
Antenna K Coefficient = 100
Wind Loading Area (Pole type) = 0.5 m2 x 0.5 m
Wind Loading Area (Tower type) = 1 m2
Maximum Continuous Duty = 3 minutes
Operating Temperature Range = 0 ~ 40 °C: Controller -20 ~ 40 °C: Rotor
Rotor Dimensions and Weight = 186 x 263, approx. 3.5 kg
Controller Dimensions and Weight = 190 (W) Ž 125 (H) Ž 150(D), approx. 2.7
kg
Power Supply Voltage = AC 100 ~ 120 V, 50 ~ 60 Hz
Power Supply Current Consumption = 0.5 A
L'ho fatta lunga, vabbe' spero che nessuno protesti.
Grazie mille a tutti, 73' Luca.