G3TXQ 6 Band Hexbeam Components.
A large portion of the parts required to manufacture the G3TXQ Hexbeam by MW0JZE are machined in house. If you have any special requirements please ask as I maybe able to help make alterations to suit your needs. All info below is based on the MW0JZE build of the G3TXQ Broadband Hexbeam Heavy Duty verson.
1. The Centre-Post (Revised 01/07/2020)
The Air Coaxial Centre-Post is a MW0JZE Unique design that has been in production since the 1st of Aug 2012 to the presant day with ZERO failures.
By design the post is tuned to 50 Ohms and is balanced giving a more symmetrical signal and is totally isolated from any other part of the structure.
The MW0JZE - G3TXQ Hexbeam Air Coaxial Centre Post is 99cm in height and material used is 35mm OD (3.5mm wall) aluminium tubing as the outer conductor with a solid rod as the centre conductor. Centre conductor is suspended on Nylon spacers to hold it central to the inside of the centre conductor. No coax is used in the construction of the centre post.
Top of post is plugged with 5cm nylon rod which is a machined for a tight fit, this gives the post 100% water tightness. Optional Xtream WX supports can be fitted upon request.
A specifically machined ring is fitted to the top of the post which is isolated from the main post to attach the support cords to with stainless steel carabiners. Support cords are Mastrant P2 with a 95KG breaking strain.
Feed is a SO-239 or N-Type if reqested. This is placed to the rear of the post behind the 20m feed studs at the very top of the centre post.
All hardware used is stainless steel and all machining is done in shop to ensure a perfect fit everytime!
From the 8th of Jan 2019 you will be required to supply your own stub mast to insert into the lower flange as it will no longer be an integral part of the center-post.
2. The Base Plate/Hub (Revised 01/07/2020)
The MW0JZE - G3TXQ Baseplate is fitted to the bottom of the MW0JZE - G3TXQ Hexbeam centrepost, this is also where the fiberglass spreaders are fitted.
Plate is formed from high strength and lightweight T6 aluminium plate, plate is 6mm thick and professionally cut in house on a CNC machine for 100% accurately cut MW0JZE - G3TXQ Hexbeam baseplates every time. Plate is finished with engraved logo and identifying numbers for spreader positions to help when assembling the MW0JZE Hexbeam.
Stop points to ensure the spreaders are inserted into the hub at the exact point to maintain symmetry
All U-Bolts and fixings on the base plate are stainless steel for maximum protection against corrosion.
Bottom flange is custom machined in house to take a maximum OD stub:
Metric: 50 – 40mm OD
Imperial: 1" 7/8 Inch – 1” 5/8 OD.
Minimum recommended wall thickness of 2.5mm / 12 SWG.
A video of how to assemble the post and Hub can be found on this link: https://youtu.be/HlQ2jnWPp2k
From the 8th of Jan 2019 you will be required to supply your own stub mast to insert into the lower flange as it will no longer be an integral part of the center-post.
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3. Fibreglass arms/spreaders
The MW0JZE - G3TXQ Hexbeam Spreaders form the shape and the framework of the Hexbeam.
Each MW0JZE - G3TXQ Hexbeam spreader comes in three (3) sections of pullwound fibreglass tubing for high strength and durability.
1 x 1.5M with 1" (25.4mm) OD
1 x 1.5M with 3/4" (19mm) OD
1 x 1M with 1/2" (12.7mm) OD
Total assembled length of 353cm, NO CUTTING OR MEASURING REQUIRED!
Element clips are fitted to the spreaders to hold the wire elements in place, there is one for each band. These are made from UV resistant non conductive materials. They are held in place with a stainless steel machine screw and nut.
The end of each spreader section is sleeved with aluminium ferrules to prevent them splitting when pressure is placed on them when they are bent to form the shape of the G3TXQ Hexbeam by MW0JZE. Two (2) cords are fitted to the ends of each spreader be means of an eyelet or similar non ferrous fixing. One (1) is to be attached to the guy ring fitted to the top of the MW0JZE - G3TXQ Hexbeam centrepost to form the bend in the spreader, the second (2nd) cord is attached to the tip of the next spreader, this forms the radius support for each tip.
The cords are UV resistant MASTRANT P2 with a breaking strain of 95KG.
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4. Wire Elements
The G3TXQ Hexbeam by MW0JZE can be monoband or multi band. Normally due to size the Hexbeam comes in five (5) or six (6) bands from 6m to 20m. Each element is a separate entity and in no way reliant to any other bands. Adding or removing any element has little or no effect on the other bands.
High Power Insulators.
As from January 2013 all G3TXQ Hexbeams by MW0JZE will have custom made insulators fitted as standard. The insulators are bespoke design produced just for G3TXQ Hexbeams specifically for high power CW and DATA users. These insulators will eradicate the possible arcing of the driven elements where high power is used on full duty modes over prelonged periods such as contests and DX-Peditions.
Element format is Driver - Spacer Cord - Reflector - Spacer Cord - Driver with polyester cords being used as the spacer cord.
Each G3TXQ Hexbeam element from MW0JZE is made from seven (7) strand copper wire with a PVC coating with polyester spacer cords, all joints are sealed with heat shrink wrapping.
Note: All elements come complete, no measuring or cutting is required
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Configuration
A G3TXQ Hexbeam is a full size 2 element Yagi beam with bent wire elements. From above the driven element resembles the shape of a letter M and the reflector resembles the shape of a letter U. The Hexbeam can come in mono band or multi band versions with little or no loss of performance in any configuration. Each band acts as a monoband 2 element yagi with no coils or traps, so no loss. The whole antenna is fed with one 50ohm feedline and will require some sort of 1:1 balun/choke as close to the feedpoint as physically possible, this is normally 20m and is close to the top of the centrepost.
Size
If you have a small area and want a monoband performance antenna then the Hexbeam will suit your needs. At only 6.5 meters across it will fit inside most gardens. The turning radius is only 3.25 meters. Compare this to a 20m yagi with a span of 10.75 meters and a turning radius of 5.75 meters.
Height
From the base of the antenna to the tip of the centre post the whole antenna is 107cm tall, this accommodates all 6 bands from 6M to 20M. As shown in the image below, 6m is the lowest band and all other bands are stacked above it.
How does the G3TXQ Hexbeam compare with other 2 element multi-band non trapped antennas? There are not many popular multi-band antennas available that are not trapped or that include the WARC bands. The first two that came to mind were the 2 element StepIR, this is a pure yagi antenna with straight elements and no traps mounted on a single boom. The second is the Optibeam OBW 10-5-10 which is more of a Moxon configuration with 2 elements for each band, wire elements and no traps. It does however use 2+ elements for 12m and 10m, not sure what this means but I guess it uses more than 2 elements on these bands in a parasitic format. I think the two comparison antennas are fair comparisons as the StepIR is a pure 2 Element Yagi, the Optibeam OBW10-5-10 is a wire antenna and the Hexbeam is a good mix of both.
Band | 2 Element StepIR | OptiBeam OBW10 5 10 | 6 Band G3TXQ HexBeam |
20 | 4.45 | 4.2 | 3.8 |
17 | 4.45 | 4.2 | 3.2 |
15 | 4.35 | 4.2 | 3.5 |
12 | 4.25 | 4.4 | 3.0 |
10 | 4.06 | 4.8 | 3.6 |
6 | 2.85 | NA | 2.7 |
Cost | £1000+ | £1000+ | £475 |
Band | 2 Element StepIR | OptiBeam OBW10 5 10 | 6 Band G3TXQ HexBeam |
20 | 21 | 22 | 22 |
17 | 16 | 17 | 19 |
15 | 13 | 15 | 16 |
12 | 11 | 15 | 13 |
10 | 9 | 20 | 16 |
6 | 2 | NA | 11 |
Cost | £1000+ | £1000+ | £475 |
Antenna | Weight | Turning Radius |
2 Element StepIR | 13.6KG | 5.53M |
OptiBeam OBW10 5 10 | 14KG | 4.3M |
6 Band G3TXQ HexBeam | 12KG | 3.25M |