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The SmarTech 27Y5S is an OWA (Optimized Wideband Array) antenna, designed for native 50-ohm impedance.
A peculiar property of OWA systems is the large bandwidth with low VSWR curve. However this does not always imply that antenna radiation properties are same throughout the whole useful band. Thanks to the special modeling and optimization work by SmarTech, the 27Y5S preserves its typical performances up to the band ends.
This antenna has a flat SWR curve covering 27 MHz and don't require the use of antenna tuners.

The quality of materials and the specific sizing of each part, makes the antenna particularly resistant even to important wind loads.

MATERIALS
The main structure is made of aluminum alloy EN AW-6060/82 UNI 9006/1 (Anticorodal 60/100), which provides excellent long-term durability against the most severe weather (ice, water, UV rays, fine particles, acid rain), and better resistance to heavy wind load.
The antenna is supplied with stainless steel parts AISI 304 (Inox Austenitic UNI / EN 10088) and steel S235JR2 (UNI 100 series), certified according to 2000/53 / CE + RoHs standards.
Element Insulators are made of Polypropylene PPC 5660, resistant to remarkable thermic excursions (certified for temperatures from -20°C to +130°C), with high load at break (ultimate tensile strength 25Mpa), excellent abrasion-resistant and volume resistivity > 1018
The antenna is made to obtain the maximum electrical efficiency, the best mechanical resistance and durability, thanks to its high quality materials. It is also suitable for installation in mountain areas and coastal (corrosive) areas.
SmarTech antennas are designed with the minimum necessary electrical/mechanical joints. So, parasitic resistances are the lowest possible so as to minimize unwanted RF dissipations.
In order to maintain its best performances, each antenna is individually checked before shipment.
ELECTRICAL SPECIFICATIONS | |
Gain | 14.6dBi @12m (39.3ft) |
Front/Back Ratio | 42.3dB @12m (39.3ft) |
Impedance | 50 Ohm |
Power rating | 5 kW |
VSWR min. @50 ohm | 1.0:1 |
Matching Method | Direct 50 ohm |
3 dB Horizontal Beamwidth | 60° @12m (39.3ft) |
Stacked Distances | 6÷9m best 7.5m - (19.6.÷29.25ft) |
2 Stacked Gain | [7.5m/24,6ft Stacking Distance] 17.2dBi @12m (39.4ft) |
2 Stacked F/B | [7.5m/24,6ft Stacking Distance] 29.5dB @12m (39.4ft) |
PHYSYCAL AND MECHANICAL SPECIFICATIONS | |
Weight | 14.8kg (32.60lb) |
Boom length | 6m (19.7ft) |
Longest element | 5.5m (18.1ft) |
Rotation radius | 4.7m - (15.21ft) |
Projected area [F=Flat - C=Cylindrical] | F = 2.76m² (23.7ft²) - C= 0.43m² (3.9ft²) |