N6CVO VHF/UHF Antenna Project
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Brian Improves His VHF/UHF Capability
Wanting to increase my 2m capabilities, and possibly add 6m, I started on a quest to rebuild my VHF/UHF antenna sysytem which had previously consisted of a single 5-element dual band yagi and nothing else.
Looking at antenna specs for high quality omni’s I found that I could get better performance than my current yagi plus the convience of omnidirectional coverage. This seemed like a win-win so the next step was to decide how much gain I needed vs how tall the antenna would be. During my research I found a tri-band omni that met my criteria plus added a part of the 6m band (vertically polarized). This antenna did sacrafice a bit of gain but was still better than my previous yagi.
For the omnidirctional antenna I chose the Diamond V2000A Triband Omni (2m,70cm, 6m). You can see the antenna on the top of my mast. Its a two part vertical with three radials, one of which is tuned for part of the 6m band.
The coax leaves the antenna, enters my shack, and feeds a Diamond MX62M Diplexer where I split the 6m off and feed it to my HF rig.
Performnce on 2m/70cm is great and I’ve made a few 6m contacts with ease.
For my directional antenna I installed a pair of Diamond A144S10’s in a phased configuration for over 14dBi gain. I still wantd to hit some 2m remote repeaters, a couple RMSGW’s, and increase my 2m FM simplex capabilities. With that in mind, and the fact I don’t have line-of-sight to these stations, I looked at high performance yagi’s and beams. I quickly eliminated placing a 20’long beam on my little rotor and became fascinated with phased yagi’s which can double the gain while narrowing the beamwidth.
You can see the pair of phased yagi’s on my mast just below the omni. Placement was a bit compromised as I’d like to have had them a bit higher, and a bit further from the omni but they seem to work great. You may also notice they are vertically polarized to match the stations I’m interested in. Performance is great but requires careful pointing of the antennas. I can now solidly get into two repeaters and a RMSGW that were previously only sporaticly heard.
I also added full lightning protection with inline surge protectors and dedicated grounding. I hope you have found this interesting.