Very interesting, I did similar testing a few years ago, the only difference was I was using Agilent equipment versus R@S
and my results were significantly different than yours ?
On UHF both antennas performed nearly identically which is to be expected because if I remember correctly both are simple 3 element designs.
whether it's a yagi or log periodic design it doesn't matter as a 3 or 4 element yagi is gonna perform pretty much identically to any other 3 or 4 element yagi and likewise a 3 or 4 four element log periodic is going to perform nearly identically to any other 3 or 4 element log periodic.
so if you're seeing a couple dbm difference between two four element antennas then you need to question your setup because something is not right. In engineering we call these sanity checks.
I mean something as simple is forgetting to move one antenna out of the near field of the DUT will cause problems. I mean you do understand that leaving say the winegard antenna anywhere within a dozen or so wavelengths of the king while the king was being tested would impact the performance of that antenna.
The bottom line is that there are so many variables when doing antenna system tests that without a video or detailed explanation of the setup it's hard to take the results seriously.
There is a reason why antenna tests are performed inside an Anechoic Chamber or for larger antennas at a remote antenna test range
By the way, I'm a retired engineer, my primary area of expertise is in RF electronics primarily microwave. I was also former VP in charge of prototype development for a well known aerospace company, many of the projects I worked on are flying in space right now.
The bottom line is your results don't seem to pass the sanity check, you're seeing significant differences in received signal strength between two nearly identical antennas at least on UHF, In Fact if I remember correctly the UHF add-on to the batwing is purely parasitic to it's active VHF side.
the king antenna is primarily a UHF antenna, so it's performance on VHF is not gonna be nearly as good as the winegard which has a dedicated VHF dipole. If anything the VHF dipole acting as a parasitic element on the UHF side is going to cause problems. Keep in mind dual band antennas are never as efficient as single band antennas, primarily because you can never eliminate all the interaction.
Anyhow if I recall correctly when I performed a similar series of tests the results were nearly identical on UHF between both antennas with the king being ever so slightly more sensitive on UHF, so you might wanna go back and review your setup, it's even possible that one of the antennas may have been defective
oh but hey good job with all the snapshots.
SCVJeff wrote:
I finally had time to buy a King Controls Jack antenna (on sale) for a shoot-out with my existing Winegard Batwing antenna with the Wingman add-on.
