Sirio CX 4-68 VHF 68-73Mhz 4m Base Antenna.

This is my main 4m Vertical Antenna,it is a 3/4 wave "J" pole. I bought this second hand from a ham radio operator in Northern Ireland (Seamus GI4SZW). I have it over 2 years an have made some very long distance contacts on it. It is a basic and light omnidirectional antenna but works very well,I would recommend it to anybody who was looking for a vertical antenna for the 4m band. 

Main 4m Vertical Antenna, top of 10m pole.

Description:
An aluminium mono-band base station antenna for use on 4m band.

Base station antenna
Mono-band
Omnidirectional
Tunable 68-73MHz by tuning chart
Protection from static discharges
DC-Ground
Made of aluminium alloy
Electrical Data

• Type: 3/4λ coaxial J-pole
• Frequency range: 68...73 MHz tunable by diagram
• Impedance: 50Ω unbalanced
• Radiation (H-plane): 360° omnidirectional
• Radiation (E-plane): beamwidth at -3 dB = 60°
• Radiation angle: 3°
• Polarization: vertical
• Gain: 2dBd - 4.15 dBi
• Bandwidth @ SWR 1.5: ≥ 1.7 MHz @ 68 MHz
• SWR. @ res. freq.: ≤ 1.2
• Max. power: 500 Watts
• Feed system / position: gamma match / base
• Connection: UHF-female

Mechanical Data
• Materials: Aluminium, Brass, Stainless Steel, Nylon
• Wind load / resistance: 97 N at 150 Km/h / 150 Km/h
• Wind surface: 0.08 m²
• Height (approx.): from 2700 to 3360 mm
• Weight (approx.): 1900 gr
• Mounting mast: Ø 35-42 mm