I currently have a 1/4 wave antenna up in a tree 22' feet high, it works great, but I'm still unable to reach some local repeaters or reach certain areas "Home to Car" around my area. So I have been looking at high gain base antennas but they are all to tall, so I decided to make a Slim Jim and do some testing with some of my toys.
Both antennas were designed using online calculators and tuned to 462mhz
I tested the antennas with a:
138mhz-4.4ghz USB Spektrum analyzer
Digital VHF/UHF SWR meter
Radio used on the test Baofeng UV82
Both antennas used 30' of rg8x coax and altitude of 7' from the ground
I was using a steady transmission close by as my reference:
The ground plane had 1-2db gain over the Slim jim when the antennas were inside the garage with the door open, the ground plane could pick up the "reference" signal better, I was a little disappointing, BUT once I moved the antennas outside the slim jim gain 2-3db over the ground plane. My current ground plane installed 22' from the ground had the same gain the slim jim installed only at 7'.
This Slim Jim likes altitude, playing around the higher it went the more gain it had over the ground plane both at the same altitude, I could only datalog the 7' altitude gain wich is about 2-3 db more than the ground plane, can't wait to test it at 22' .
So far I recommend the Slim Jim over the 1/4 wave ground plane, but I still need to do some testing at 22' and compare. hopefully tomorrow if it stops raining , hurricane Mathew is entering FL tonight lol.
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cdesigns
I currently have a 1/4 wave antenna up in a tree 22' feet high, it works great, but I'm still unable to reach some local repeaters or reach certain areas "Home to Car" around my area. So I have been looking at high gain base antennas but they are all to tall, so I decided to make a Slim Jim and do some testing with some of my toys.
Both antennas were designed using online calculators and tuned to 462mhz
I tested the antennas with a:
138mhz-4.4ghz USB Spektrum analyzer
Digital VHF/UHF SWR meter
Radio used on the test Baofeng UV82
Both antennas used 30' of rg8x coax and altitude of 7' from the ground
I was using a steady transmission close by as my reference:
The ground plane had 1-2db gain over the Slim jim when the antennas were inside the garage with the door open, the ground plane could pick up the "reference" signal better, I was a little disappointing, BUT once I moved the antennas outside the slim jim gain 2-3db over the ground plane. My current ground plane installed 22' from the ground had the same gain the slim jim installed only at 7'.
This Slim Jim likes altitude, playing around the higher it went the more gain it had over the ground plane both at the same altitude, I could only datalog the 7' altitude gain wich is about 2-3 db more than the ground plane, can't wait to test it at 22' .
So far I recommend the Slim Jim over the 1/4 wave ground plane, but I still need to do some testing at 22' and compare. hopefully tomorrow if it stops raining , hurricane Mathew is entering FL tonight lol.
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