Grazioli G-Max 10m/11m vertical antenna

The world's only Collinear Ground Plane for 10 or 11m

The Grazioli "G-Max" is a vertical Collinear Ground Plane antenna with high gain, that can be used either for the 27 MHz CB-band or the 10m amateur band. It can used within the frequency range of 27 - 28.5 MHz, tuning to the desired frequency is accomplished by changing the antenna length, suing the supplied table. The radiator is made of two distinct sections, fed in phase through a special aluminum coil positioned on the whip.

The feed is direct and takes place in the lower part of the whip that has a length of about 1/4λ, then through the phasing correction coil the RF signal goes to feed in phase also the upper part of length about 5/8λ.

The result is that the whole stylus of about 10.3m radiates in phase with a gain of almost 6dBi and a very low radiation angle (typical about 8°).

 To achieve the desired "gorund plane" effect, 4 robust, 2.7 m long quarter wave radials are used.

Built on the mechanics of the well-proven FE10V this antenna has exceptional performance comparable or better than a 2 elements Yagi, but with the advantage that G-Max is omnidirectional and does not need to fear comparison with any other vertical antenna on the market, whether they are 5/8 type, J-Pole, or other types.

The details also show that the manufacturer is breaking new ground instead of relying on standard solutions: For example, the antenna connector is not a standard SO239 socket, as is often used, but an SO-239 socket developed and manufactured by Grazioli itself. This part has a characteristic impedance of 50 ohms and is designed for frequencies up to 500 MHz, withstanding sustained high RF power.

The housing is made of CW614N nickel-plated brass, while the pin is plated with 24-karat gold to prevent oxidation and is equipped with a PTFE insulator that maintains its centering and elasticity to prevent contact loss.

The entire assembly is protected by a special elastomer sheath that prevents water and moisture ingress.

THE PHASING CORRECTION COIL

The G-Max coil is placed at the ends of the two central radiating sections. It performs three functions of extreme importance for this type of collinear antennas:

1. Delaying by 180° the phase of the RF signal between the first section at 1/4 Lambda and the second section at 5/8 Lambda, so that the whole radiating part (whip) radiates in phase.
2. To compensate for the strong capacitive reactance present on the top 5/8 section thanks to its intrinsic inductive reactance
3. To transfer all the power fed to the top section without losses.

All this is made possible thanks to the high "Q" factor of the coil, designed to perform all three functions mentioned in the best possible way.

With the included corrosion-resistant mounting material, the antenna can be attached to masts with diameters of 40 - 54 mm.

NOTE: G-Max is supplied with 3 guying clamps. Due to the length of the antenna, we highly recommend guying with suitable guying material.