649,00€
Price VAT included
Vertical Multiband 1/4 λ Ground Plane
HF 40, 20, 17, 15, 12, 10m + VHF 6m
Powered at the base
Max Input Power: 1500W SSB @ 40m – 3 kW other bands
Total Height: 8.97 m
Antenna Weight: 8,5 Kg
In stock
Main Features
Vertical multiband 1/4 λ Ground Plane base-fed antenna for the following HAM bands: 40, 20, 17, 15, 12, 10 and 6m.
Extremely robust construction in AW6063-T66 aluminum alloy and CNC machined parts from solid stock.
Supplied with high-quality 304 and 316 stainless steel fasteners for long rust-free operating life.
High input power, up to 1500W SSB @ 40m - 3kW on other bands.
Detailed assembly manual and serial number that identifies the production batch and construction data.
For our tubes, we used the best material that can be used for antenna construction; it is the Aluminum, Magnesium and Silicon alloy named AW6063-T66, hardened to the T-66 state. It gives the stylus exceptional strength, which is made by extrusion and then cold-drawn.
Of extremely robust construction, the central stylus uses 42x2mm diameter tubes at the base and 19x1.25mm diameter at the tip, while the side stubs and ground plane radials are made of 13 and 10mm diameter telescopic tubes.
The ground plane is formed by 4 horizontal radials of approximately 2.7m in length, and the vertical stubs are held in place by 3 crossbars, the first connected to the base of the stylus is made of CNC-machined rectangular-section aluminium tubing, and the other 2 of thermoplastic material, one with 4 arms in the middle part, and one with 2 arms in the upper part.
All hardware is made of stainless steel, the tubes are secured with robust, quality stainless steel AISl-316 clamps, brackets, hardware, and U-bolt and V-bolt U-bolts are made of AISl-304 stainless steel.
| Electrical Data | Mechanical Data | |||||
|---|---|---|---|---|---|---|
| Type | Ground Plane 1/4 λ with parallel stubs | Materials | Aluminum Alloy AW6063-T66 hard drawn tube, Fiberglass, Brass, PTFE. All hardware are made of SS AISI-304 and 316 | |||
| Frequency Range | HF 40, 20, 17, 15, 12, 10 + VHF 6m | Wind surface area | 0,42m2 | |||
| Impedance | 50Ω Unbalanced | Wind survival (no ice) | 130 Km/h (braked) | |||
| Radiation Type | Omnidirectional | Total Height | 8,97m | |||
| Polarization | Linear – Vertical | Stylus length | 8,4m | |||
| Gain | 0 dBd – 2,15 dBi | Radial length | 2,7m | |||
| Bandwidth with SWR 2:1 | 40, 20, 17, 15, 12 10m full band, 6m > 1.5 Mhz | Mounting mast bracket | ø 40-54 mm | |||
| SWR @resonance | ≤1.5:1 (Typical) | Antenna Net weight | 8,5 Kg | |||
| Max. Input Power | 1500W SSB @ 40m - 3kW other bands | Package dimensions | 14x14x145 cm | |||
| Feed system | Direct - connected to DC ground | Weight in pack | 9,95 Kg | |||
| Input connector | UHF female - PTFE insulator, gold-plated centre pin | |||||
Diagramma di SWR tipico 6m a 8 metri da terra
Diagramma di SWR tipico 12/10m a 8 metri da terra
Diagramma di SWR tipico 17/20m a 8 metri da terra
Diagramma di SWR tipico 40/20m a 8 metri da terraThe basic idea was to make an efficient antenna, without using traps that reduce efficiency, and without using impedance transformers that limit the applicable power.
Based on these assumptions, we realised MV7, which by using resonant elements parallel (stubs) to the central stylus, allowed us to realise an efficient antenna on all bands covered.
Technical Details on Operation
MV7 is built on the basis of the well-established MV6, from which it takes almost all of its mechanics, with the exception of the central stylus, which is now Dual Band (40+20m), obtained by adding a coil with a capacitive cap, which decouples the lower part of the 20m band and, at the same time, provides adequate inductive charging for the 40m band.
The remaining radiating part, which is approximately 2.2 metres high, consists of two telescopic tubes designed to offer minimal wind resistance, is adjustable, design for perfect calibration across the entire 40 m band.
The MV7 uses a modified ground plane compared to the MV6, with an innovative system called DBFC, which stands for Dual Band Folded Counterpoise, making this system unique (patent pending).
The DBFC system creates a dual-band electric counterweight, where a highly flexible and lightweight 1mm diameter AISI316 stainless steel 19-strand cable is anchored at the tip to one of the four radials. The significant difference in diameter between the 10 mm aluminium radial and the 1 mm stainless steel cable means that the high impedance at the junction point allows only the lowest band of 40 m to flow through the cable (hence the dual-band function), while the higher bands, e.g. 20 m and above, function as before.
The total length of the stainless steel cable, plus the length of the aluminium radial, form a single counterweight of approximately 1/4 wave at 40 metres, which is then folded back towards the next two radials, reducing the overall size and avoiding the need to install awkward wire radials or resort to loaded radials.
NOTE:
If used in very windy areas, bracing with non-conductive cables using the supplied fifth wheel is recommended.
The RF Choke for attenuating common mode currents
Now supplied with the MV7 is an original FAIR-RITE Made in the USA FT240-43 ferrite toroid for “Home Made” construction of your high-performance Choke. This arrangement allows you to significantly attenuate common mode currents in the HF band (1.8-30MHz), which could reduce the performance of your antenna.
Material not supplied at customer's expense for fabrication:
- No.2 PL259 connectors suitable for the type of cable you intend to use.
- (1 PL259 + 1 SO239 in case of using plastic protection box).
- Approximately 1.2m of good quality coaxial cable, such as RG58 for continuous powers up to 300 Watt AWG @ 30MHz, or RG142BU in Teflon for continuous powers up to 1500 Watt AWG @ 30MHz.
We absolutely discourage the use of cables with FOAM foam-type dielectric (white spongy dielectric) because they cannot be wrapped around the toroid without compromising its electrical characteristics.
UHF connector
The antenna connector is not the commercial SO-239 type used by most manufacturers. Our connector is designed and built directly by ourselves; it has a true 50 Ohm characteristic impedance and is rated up to 500 MHz. We have created a reliable connector capable of withstanding 5 kW of continuous RF power at 30 MHz and greater than 3 kW at 50 MHz.
The body is made of CW614N nickel-plated brass, while the pin is plated in 24K gold to avoid oxidation and is equipped with a 4-fin insulator that maintains its centring and elasticity to avoiding contact losses.
The insulating material is PTFE, one of the best insulators due to its exceptional electrical and thermal properties (low dielectric constant and reduced loss factor, operating temperature from -100 to +260 °C). The assembly is protected by a special elastomer hood that prevents water and humidity infiltration.
The fixing bracket
Is made of 2.5 mm-thick AISI 304 stainless steel and is attached to the antenna tube by means of a clamping system, creating an extremely robust mechanical lock.
The mast coupler is consists of an M6 V-Bolt in AISI 304 steel and column nuts for easy, secure tightening.
