Introduction - why a patch antenna? Recently I switched to the Aomway Commander Goggles (review here) which have built in receiver diversity. This means the receiver with the antenna attached with the highest RSSI value is fed to the displays. Aomway are well known for making a great omnidirectional antenna but a rubbish patch antenna is included with the goggles. The advantage of mixing antenna types when you have true diversity is that omnidirectional antennas will cover all directions good enough whereas patch antennas (directional) will cover in the direction the antenna is 'pointing' only but with the benefit of much less signal loss. What does this mean in the real world? When the vtx signal is coming from the directional path of the patch antenna you can go further and the signal can be better received from behind trees and other obstacles. The omnidirectional antenna will pick up all the other areas - behind, beside and in front. What kind of patch antenna? Since the Aomway patch was rubbish I went looking for a cheap alternative that was small so that I wouldn't have to continually take on and off my goggles. Patch antennas come in linnear or circular polarised, just like any other vtx antenna. Since I run circular polarised antennas in my 5" freestyle and race quads where I'm likely to travel further or need guaranteed reception I went with a circular polarised patch - specifically Right Hand Circular Polarised (RHCP) to match my cloverleaf and pagoda RHCP antennas on my quads. Note there are few linnear patch antennas but I have heard good things about the Menace RC Bandicoot. This would be great for micros which pretty much exclusively use linnearly polarised dipole antennas. Why the RealACC 8dBi patch antenna? The RealACC 8dBi patch antenna looked like it met my needs on paper and is only $7 on banggood. Definitely worth a try! It comes with option of RHCP or LHCP (I chose RHCP) and SMA or RP-SMA (Aomway Commander are SMA) which means there are options for everyone. Since the SMA connectors come out of the Aomway Commanders at a 45° angle, I also bought some 45° SMA adaptors so the patch antenna would point straight ahead.  Not the best image in the world but should give you a sense of scale on the goggles - fairly compact. In use The best test for the patch antenna was when I mistakenly left off my omnidirectional cloverleaf antenna during racing. Below is DVR footage of that run with 3 or 4 others on the track at the same time and everyone running 25mW vtx power only. One of the pilots had a defective VTX antenna and was causing video issues for all the other pilots except me. Of course this is anecdotal but throughout the day I had crystal clear video. I'm just glad all racing was done directly in front of me! Conculsion Since then I've used the RealACC patch antenna with all my quads - both with circularised polar and linnear antennas. I'm really enjoying the extra range this gives me without sacrificing portability. The Pagoda triple feed patch antennas are well recognised as being excellent but I wasn't willing to stomach the larger size and lesser portabilty. With a young family I don't get to fly as much as I'd like so when I am out I want to fly more and spend less time setting up. I'm really pleased with this little patch antenna for what I wanted.
2 Comments
QuadifyRC
10/4/2018 11:30:16 am
Hey there. Yeah it is definitely directional looking at the element and using it - tried using this antenna only and it was very much focused to a wide beam in front of the antenna. In fairness though their description is awful and simply not correct. Leave a Reply. |
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