Don't be misled into thinking you are buying something you are not.
Within this site I have provided a number of designs for self-build which allows hams to build antennas themselves that are as good or better than options they can buy. In the past I have sold the rights to a number of antenna manufacturers around the world to reproduce these public domain designs. However, these are my early work, they are older designs and while they work well, they are far and removed from the most current design releases and lack many of the enhancements of my most modern designs.
3.5 Years ago, I setup InnovAntennas with Bill AA7XT and through this company (and the now acquired Force 12) , we provide the very latest designs. The LFA-R, LFA2, LFA-Q the OP-DES and the latest LFA designs are only available through InnovAntennas, no one else.
My design work has slowed in the public domain but this is only because commercially it has been taken to new heights. We design and build LFA Yagis for government & defence applications both at home and abroad and recently completed an HF LFA Yagi array (multiple antenna stack) to be used as an over the horizon radar system for defence purposes.
Newly designed LFA Yagis are on service in the Middle East right now and even on destroyers off of the African coast where they help track pirate activity. So why select InnovAntennas Yagis if you are choosing to buy? One antenna is not the same as another and a good understanding of both electromagnetic design as well as the impact of any mechanical structure needs to be understood and appreciated to ensure performance is achieved. You can be assured of a fully rounded, fully finished product from InnovAntennas.
It does not just stop there either. The new range of LFA, LFA2 and LFA-R (LFA-R is an LFA Yagi modelled without any reflector element) produce very high levels of gain compared with the public domain versions on this site. However, much development effort has gone into ensuring design stability in addition to huge increases in gain over the publicly available designs, has been achieved. Why is this important? Anyone that has purchased and used a 'high gain' Yagi will know that often, the said Yagi is totally unusable when it rains (or is covered in ice) as a result of inherent design flaws.
Above is a photo of a recently installed (June 2014) 5 element LFA-Q Yagis by InnovAntennas installed at G8VR. These LFA-Q's are just 4.3m long but individually they provide over 11.6dBi gain and do this with stability not seen in such high gain designs previously experienced by ham radio operators. Note the very strong mechanical structure of this antenna with an under-boom that provides 'upward' support in order that boom sag is completely removed.
Now take a look at the below plots. The first image is the predicted impedance curve of a 30 element X-pol LFA Yagi on 432Mhz. X-pol Yagis have always been very difficult to get right, especially on 432Mhz. Impedance is compared in this plot and the second one (which is the built antenna analyser results) as impedance is the most sensitive parameter and shifts before anything else if the antenna is not right.
Software prediction of the 30 element 432MHz LFA Yagi
Analyser measurement of the finished antenna
Pay careful attention to the above plots, not the lead-in and lead-out shape of the curve and exactly where the antenna sits. This is not just somewhere close, this is a near-perfect replication of the software model in the real-world. This is one reason commercial entities, governments and defence organisations are employing my services to design and produce their antennas and this is something you can share in too.
So is it just about cost? You decide but you can be assured that if you decide that you want to buy a Yagi ready-built, it will be the latest design and any support and set-up help will be provided directly by the antenna designer himself, i.e. Me!
Any questions within regards to your antenna requirements, be it station layout planing for a contest station or just how far apart your antennas on a single mast should be, I am happy to help.
Until next time,
Justin G0KSC
justin 'at' G0ksc.co.uk