When I saw this thing I thought, yea right, a piece of pcb with a pattern of a palm tree leaf on it, what nonsense are they trying to sell me this time. Then, for no peticular reason, when I read the designer 's documentation, I started to get curious. I think this gentleman had put a lot of effort and energy into explaining and documenting his antenna design, and this together with the publication of test results from an independent company specialized in RF measurements of antennas, I just had to continue to investigate this. After a bit of duckduckgo'ing (google'ing for people who love privacy .... they say) this turned out to be a no nonsense antenna, on the contrary this was one where there is a fair amount of fuss about , because of the return size/ performance appears to be large. When I also saw the more than reasonable price that was being asked, I had wasted more than 5 times the money on other so-called pcb antennas, I thought, ok, I want to know the bottom things about this, and I ordered one. To make a long story shorter now, the first thing I did when I had this thing in my hands 2 days after ordering, was connecting it to my cheap cinese spectrum analyzer in combination with a likewise cheap VSWR bridge, it can only measure up to 1.5GHz, this is a fraction of the bandwidth of the vivali palm leaf antenna, I know , but better than nothing , right??. Well this was a very pleasant surprise, it turns out that what I can measure is entirely consistent with what is being told by the designer, not that I did not believe this gentleman but it is in my nature to check things as much as I can for myself . This has completely reassured me that this is "the real thing" and not "fake news" :-) This vivaldi palm leaf antenna, 2 of them, one vertikally and one horizontal polarized mounted, are now in use on my Huawei B525 4G + internet modem. Signal level of this went from -90dBm to -70dBm, signal-noise went from 10dB to 15dB and as a result of this the download speed went up from 30-50Mb / sec to 100Mb / sec, and sometimes even more than that. All this thanks to 2 Vivaldi antennas aimed at the nearby 4G + mast (+ - 400m). Well I know there will be people who read this, who will think "Bullshit", well in that case I like bullshit, no fake news here people, I am telling you exactly what I am experiencing. My complements to the designer, this is a job more than well done, amazing. Regards,
(forgive me for my maybe funny name sounding, but I am from Belgium .... now that's what i call a excuse, not?) :-P
Hi Franky, thanks for your amazing review. So pleased you like them. I totally dig your initial scepticism. I did spend a lot of time on the design and simulation and owe a massive debt of thanks to AntennaTestLab for the final measurements. It's also really great to hear your experiences with 4G. Thats a great solution for those with slow internet and on the edge of 4G coverage.
I have one each of the 300Mhz and 800Mhz antennas and also bought an additional 300Mhz for a friend. The additional engineering and design information provided by hex-and-flex is extremely useful and welcome. One of my antennas stays attached to a LimeSDR (RX side) and the other to Baofeng hand-held, used in a location where reception is something of a challenge for most antennas. The suction cups are a nice touch.
I don't have equipment to check the performance of this board, but that has already been done. I've never seen a board with such thick coatings and with the data printed on the coating. There will be no question of what this is in the future. I did put it on the various SDR boxes I have around that cover those frequencies and it picks up more signals than I can identify. N0UU
Glad your happy with it. I am a big fan of parts with the basic specs printed or engraved on them so once I had the reliable measurements from AntennaTestLab I had to do it. I used to use old HP directional couplers with the full S parameter charts printed on them, Really handy. I hate having to look on the internet for an obscure part number every time especially if there is no manufacturer name or they went out of business.
I received the Vivaldi antenna on time and without any problem. It was properly packed and protected. The antenna is exactly what was described by the seller and it is superbly documented online. Thanks for everything.