Now supplied with original FAIR-RITE FT240-43 ferrite toroid Made in USA
Multiband 1/4? Ground Plane vertical antenna fed at the base for the following HAM bands: 20, 17, 15, 12, 10 and 6m.
Extremely robust construction in AW6063-T66 aluminum alloy and parts machined from solid using CNC.
Supplied with quality INOX 304 and 316 stainless steel screws for long rust-free service.
High input power capability, up to 3Kw continuous All-mode.
Detailed assembly manual and serial number identifying the production batch and construction data.
For our tubes, we used the best material available for antenna construction: the Aluminum, Magnesium, and Silicon alloy known as AW6063-T66, tempered to T-66 state. This gives the element exceptional strength, achieved through extrusion and subsequent cold drawing.
Of extremely robust construction, the central element uses tubes with a diameter of 42x2mm at the base and 19x1.25mm at the tip, while the side stubs and ground plane radials are made of telescopic tubes with diameters of 13 and 10mm.
The ground plane consists of 4 horizontal radials approximately 2.7m long, and the vertical stubs are held in position by 3 cross-braces: the first connected to the base of the element is made of rectangular section aluminum tubes machined with CNC machines, and the other 2 are made of thermoplastic material, one with 4 arms in the middle section, and one with 2 arms in the upper section.
All screws are made of stainless steel, tube fastening is done with robust quality stainless steel AISl-316 clamps, and the brackets, screws, U-bolts, and V-bolts are made of AISl-304 stainless steel.
| Electrical Data | Mechanical Data | |||||
|---|---|---|---|---|---|---|
| Type | Ground Plane 1/4 ? with parallel stubs | Materials | Cold-drawn tube in Aluminum alloy AW6063-T66, Fiberglass, Brass, PTFE. All screws in INOX AISI-304 and 316 |
|||
| Frequency Range | HF 20, 17, 15, 12, 10 + VHF 6m | Wind Surface | 0.4m2 | |||
| Impedance | 50? Unbalanced | Wind Resistance (without ice) | 130 Km/h (guyed) | |||
| Radiation | Omnidirectional | Total Height | 6.75m | |||
| Polarization | Linear - Vertical | Radiating Element Length | 6.2m | |||
| Gain | 0 dBd – 2.15 dBi | Radial Length | 2.7m | |||
| Bandwidth with SWR 2 | = 20, 17, 15, 12 full band 10&6m > 1.5:1 | Mounting pole | ø 40-54 mm | |||
| SWR at resonance | =1.5:1 (Typical) | Net Weight | 7.8 Kg | |||
| Max applicable power | 3000 continuous Watts all modes of emission | Packaging Dimensions | 14x14x145 cm | |||
| Feeding | Direct - DC grounded | Packaged Weight | 9.2 Kg | |||
| Connector | UHF female - PTFE insulator, gold-plated center pin | |||||
The basic idea was to create an efficient antenna, without using traps that reduce its efficiency, and without using impedance transformers that limit the applicable power.
Based on these assumptions, we created MV6, which, using parallel resonant elements (stubs) to the central radiating element, allowed us to create an efficient antenna across all covered bands.
A high-performance Multiband Antenna
The antenna consists of a central radiator for the lowest band of 20m flanked by 4 lateral stubs that resonate on the higher bands 17, 15, 12, 10 + VHF 6m. The lateral stubs are a full 1/4 wavelength long without traps that would reduce their efficiency. The antenna is fed directly without the use of adapters or impedance transformers, which would introduce losses and limit the applicable power. It is equipped with a high-impedance inductor that creates a DC short circuit, grounding any disturbances caused by atmospheric events and/or electrostatic discharges.
Tuning is done by adjusting the telescopic parts of the stubs and the central element. Each frequency is independent and does not interact with other bands, except for the 17m band, which also determines the 6m resonance. We recommend using a graphical antenna analyzer such as Rig-Expert or Nano VNA, which makes tuning much easier.
NOTE:
If used in very windy areas, guying with non-conductive cables is recommended using the supplied mast clamp.
It is advisable to use a CHOKE installed immediately below the connector to prevent possible RF feedback on the coaxial cable.
The Choke to attenuate common mode currents
The MV6 now comes with a supplied FT240-43 ferrite toroid original FAIR-RITE Made in USA for building your own high-performance choke. This measure significantly attenuates common mode currents in the HF band (1.8-30MHz), which could reduce your antenna's performance.
Customer-supplied materials not included for construction:
- 2 PL259 connectors suitable for the type of cable you intend to use.
- (1 PL259 + 1 SO239 if using a protective plastic box).
- Approximately 1.2m of good quality coaxial cable, such as RG58 for continuous power up to 300 Watt AWG @ 30MHz, or RG142BU in Teflon for continuous power up to 1500 Watt AWG @ 30MHz.
We strongly advise against using cables with FOAM dielectric (spongy white dielectric) because they cannot be wound around the toroid without compromising their electrical characteristics.
The UHF Connector
The connector is not a commercial SO-239 type as used by most manufacturers. The connector was designed and manufactured directly by us, has a real impedance of 50 Ohm and can be used up to 500MHz. We have created a reliable connector capable of handling the passage of 5kW continuous CW at 30MHz and more than 3kW at 50MHz.
The body is made of nickel-plated CW614N brass, while the pin is 24K gold-plated to prevent oxidation and features a 4-flange insulator that maintains its centering and elasticity, preventing loss of contact.
The insulating part is made of PTFE, which is one of the best insulating materials due to its exceptional electrical properties (low dielectric constant and reduced loss factor) and thermal properties (operating temperature from -100° to +260°) and is protected by a special elastomer cap that prevents water and humidity infiltration.
The Anchor Bracket
Made of 2.5 mm thick AISI304 stainless steel. It is fixed to the antenna tube using a clamp system, creating an extremely robust mechanical lock.
The mast attachment is made with M6 V-Bolt U-bolts in AISI304 and column nuts to facilitate tightening.
