Perfecting the X-pol - All elements MUST be perfectly aligned and centered

If you want an X-pol Yagi and wish to maintain the software predicted noise figures (G/T) the ONLY way this can be achieved is with perfectly centres X and Y planes. If the elements in each plane are off-set or even have a matching section (such as a T-match) extend into the opposing plane, pattern distortion and noise figure degradation WILL occur. It does not matter what you read or see if noise figures on paper, those models did not include the off-set!
Some customers take the advice and do things right, Constantin, KG6NK is one of those guys. We built his 4 x 22el 144MHz low noise LFA Yagis with perfectly centred, thru-boom elements and he built an H-frame to support the system completely from fibre glass. Simply adding a small piece of fibreglass to the ends of metallic supports does not cut it, the remainder of the metallic tube WILL conduct and WILL degradation performance. Constantin had excellent results with his 2 x 22el built this way so decided to upgrade to 4 and the installation is almost done!
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Almost there! a 4 x 22el X-pol low noise LFA Yagi system with perfectly centred elements with just cables to connect, at KG6NK
All coax cables, when completed will exit the rear of the antennas and the forward-most coax cable / ferrite choke is curved and has a rotational exit from the feed point in order there are no, flat surfaces (coax cable is metallic too!) in order to minimise any potential interaction.
When investing in VHF/UHF systems for low noise applications, particularly EME, it is important to do it right, not what best works for mass production purposes. Ensure you get antennas manufactures the best way to ensure excellent results. If this sounds like the way you want to have your EME system configured, let us know and InnovAntennas and we will give you all the help and advise you need, post and pre-sale.
X-pol Configuration Check List:
• Perfectly centred elements with no off-set (particularly important on 70cms)
• Absolute minimal contact with any element (no feed point boxes or structures)
• Rotational exit of coax/balun from the feed point
• Rear exit of all coax cables
• Rear Splitter mount to hold splitter rearward for minimal coaxial runs (in photo)
• Non-metallic H-frame
Of you want the best in low noise Yagi replication – look no further than InnovAntennas
Photo: Almost there! - Constantin sent us this photo of his system almost ready to go. Next step, cable connections and finalisation!
Justin, G0KSC - InnovAntennas
Feed Point Boxes, Why?

Feed Point Boxes, Why?


The intricacies of VHF/UHF Yagi antenna design are notably influenced by real-world implementation choices, with the feed point box playing a pivotal but negative role. Many software models overlook this component, leading to predictions that are not a true representation of what the end-user experiences. Not only does it retain moisture over time, but its presence also distorts the antenna pattern, influences the noise figure, and ultimately degrades the G/T performance. This degradation contrasts sharply with the model's predictions if the feed point box was omitted. The only discernible benefit of the box is aesthetic, making the Yagi appear more polished.

InnovAntennas confronts these challenges head-on. We prioritise the use of RF-friendly materials and design with minimal supporting structures. We avoid feed point boxes entirely, sidestepping their associated problems. Instead, we employ a direct connection using small, durable user-serviceable connections. This ensures longevity. Additionally, it offers users easy maintenance without the need for proprietary parts from InnovAntennas. Our Yagis strike a harmonious balance between the perfection of a software model and the practicalities of real-world construction, delivering industry-leading performance by setting new standards in real-world model replication.

For those who aim for the apex of low-noise performance, with a steadfast commitment to design integrity and longevity, the low noise LFA Yagi stands unmatched.  we've completely eliminated the traditional feed point box, commonly susceptible to moisture retention and the ensuing performance deterioration. This deliberate engineering choice ensures a moisture-free, low-loss, low noise connection - a feature notably absent across the industry and one that ensures our G/T results are closer to predicted noise figures than anyone else. Our approach safeguards against the common pitfalls of water ingress, which can lead to tuning fluctuations and potential transceiver damage from impedance discrepancies. The LFA Yagi offers a universal pillar of dependability and superior performance in any environment, catering to those who prioritise peak performance without compromise.

FM5CS X pol A

4 x 20el 144MHz low noise LFA Yagis at FM5CS - Perfectly centred elements and absolute minimal supporting structures around the antenna to ensure modelled pattern replication.


For enthusiasts seeking unrivalled low-noise performance, the low noise LFA Yagi from InnovAntennas stands as a paragon of excellence. Our innovative design approach centres on more than just avoiding moisture; it vitally focuses on preventing the detrimental shrouding of the dipole, the Yagi's most vital component. Conventional feed point boxes, commonly found in traditional designs, cover a significant part of the dipole's centre, inadvertently inducing noise and degrading both the noise figure and the G/T performance. Discarding this standard approach, the LFA Yagi delivers an unobstructed, low noise experience, ensuring that the antenna's real-world performance closely mirrors the optimised theoretical models. This dedication to design integrity propels the LFA Yagi beyond conventional limitations, offering an experience unparalleled for the discerning operator.

Justin G0KSC - InnovAntennas


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