Back in October 2014, I built a 2X14 RPOL antenna system and have had extremely good success with it. I could not resist to the temptation and the technical challenge of pushing the envelop to the extreme, so I decided to go a step further, and built the first ever "Rear Mounted 16-Element LFA Rotatable POLarity Antenna". With a 38-foot long boom, this monster is truly enormous, and believe me, it really feels that way when you hold the whole thing in your hands from the Rear End!
The antenna has an excellent Forward Gain of 17.5 dBi (plot below) and is equipped with the same Rotatable POLarity capability (RPOL) used in all my previous designs to significantly enhance its efficiency and effectiveness. After accounting for the "absence of losses" typically involved in a 2X or 4X Yagi phasing scheme, the forward gain performance of this antenna is roughly equivalent to a 2X12 or 4X7 array, with superior G/T, which is not bad for a Single Yagi!
The boom is entirely collapsable into small 4 to 6 foot sections, which makes it a perfect companion for high performance portable operation. The antenna can be setup on a simple umbrella base and DOES NOT require any phasing cables, cross boom / H-frame, power divider, etc. One can also notice on the picture that the umbrella base is secured onto a small "furniture dolly". In other words, we are looking at an "antenna on wheels", which allows rolling the antenna from one side of the backyard to the other with amazing ease!
This high performance antenna system shines by its simplicity and flexibility. In addition to delivering an outstanding Forward Gain of 17.5 dBi and G/T figure of 0.18dB, just like it is the case for all my antennas, the RPOL provides Absolute Polarity Flexibility, which can amount to up to 3dB advantage over a conventional H/V and XPOL systems. Now, when one considers the potential "Signal to Noise Ratio" advantage, my RPOL antennas can actually outperform conventional H/V and XPOL systems by more than 3dB. See Section 34 for a live example of this, where an extreme 15 dB man-made noise was completely wiped out by taking advantage of the FULL rotatable polarity flexibility. No other schemes (Noise Blanker, etc.) could deliver such an effective noise suppression performance. See also Section 21 on this subject.
My second QSO with this antenna was with a Single Yagi, K3IB, who was running ~1300 watts into a 12-Element with some Ground Gain (video clip above).
This 16-Element RPOL antenna will replace the 1X13 RPOL LFA in the backyard and will be also used for the Moon Echo project. I am very excited with this new addition to my collection! Now my antenna farm counts a 2X14 RPOL system on the roof, a 1X16 RPOL LFA in the backyard, and 2X13 RPOL LFA temporarily hanging on the fence, but not for too long..... (next project).....
More to come as I experiment further with this 16-element unit.
Back in October 2014, I built a 2X14 RPOL antenna system and have had extremely good success with it. I could not resist to the temptation and the technical challenge of pushing the envelop to the extreme, so I decided to go a step further, and built the first ever "Rear Mounted 16-Element LFA Rotatable POLarity Antenna". With a 38-foot long boom, this monster is truly enormous, and believe me, it really feels that way when you hold the whole thing in your hands from the Rear End!
