My back yard is small so I have difficulty installing even the G5RV as a flat top so I decided to give a sloping-v a try so I could get on 80 meters with better results. The antenna was installed about a month ago.
I have been reading on N.V.I.S. and plan to make a N.V.I.S. antenna over the winter. This is some of my reasoning on using the G5RV in different configurations including N.V.I.S.
My sloping-v is not the traditional as the ends are about 7-1/2 feet off the ground. The apex is about 25 feet from the ground.
So far I have worked most of the South Eastern states with this antenna on 80. Not DX by a long shot, but much better than I have been able to work on any other antenna.
Plans are to try this at more of a slope to bring the ends closer to the ground as a true sloper would require and to try it with terminating resistors. The G5RV is not resonant on any single ham band especially using this configuration. I do not have the ends terminated nor am I using a counter poise. I have radials on the vertical and they provide the ground plane for the sloper.
Checking the antenna with my handy-dandy but how accurate MFJ antenna analyzer the antenna has a 1.2:1 VSWR @ 50 ohms @13.848 MHz and 1.5:1 @ 50 ohms @14.000MHz. The analyzer shows a 1:1 VSWR @ 50 ohms @35.565MHz and again at 75.6935 MHz. I do not fully trust the MFJ analyzers, but they get close. I question their accuracy because they will indicate 1:1 at anywhere from 35 to about 60 or 70 ohms. I have used several and find the same results. I plan to check this antenna with a GR bridge when the weather gets cool enough.
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| This is the G5RV. A bit difficult to see the V. |
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| Feed point is the white in the lower right corner. |
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| End supported by 2 LCSS aluminum poles |
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| Each end pole is held by a section of PVC pipe attached to angle iron driven into the ground. |
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| This is the apex about 25 feet high. Guy plate is between the 5th and 6th section of a mast made from MS-44 aluminum sections from an AB-155/A/U |
Hi,
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I noticed from your pictures that your ladder line does not drop straight down from the top of the Inverted V. The ladder line on the lower bands helps radiate your transmit signal, there fore, it’s important that the ladder line drops straight down its full length from the top of the inverted v and is kept at least 8” - 12” or more away from any metal. My G5RV Inverted V that I installed on January 1, 2000, 2 weeks after getting licensed at age 17, is 60’ high with both leg ends around 10’ - 14’ off the ground. The inverted v is set up like the letter A leaning against the top of the galvanized push up pole at roughly a 45º + - angle. This set up has had fantastic performance on all bands from the bottom portion of the 80m general SSB portion up to the 10m FM portion. 1.1 SWR on all bands using either my late 80s IC-761 internal auto tuner or IC-7300 internal auto tuner. I’v worked the world and twice on Sundays with just 100w. And when 100w doesn’t quite cut it, more times then not 300w - 400w is all it takes to get the job done. I’v even had very good success on 10m with just 100w! In my opinion you cant beat the performance of a G5RV Inverted V for its low cost and maintenance. It’s the perfect 80m - 10m antenna for a new ham or a ham new to HF. Just like I was when I got my Tech No-Code licenses at age 17 back in December ‘99. I could easily afford a high dollar tri-band beam, but then all I would have is a good performing antenna on only 3 bands. The G5RV Inverted V isn’t the “perfect” antenna (but then again what antenna is?), but if installed correctly, it’s a very good performing antenna. - KD5ITM -
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ReplyDeleteOne more thing to note, an Inverted V does not need a counter poise or any type of a ground plane or ground plane radials since it’s not a vertical antenna. Set up like I have mine where the legs are like the letter A leaning against the top of the pole at roughly a 45º angle give or take, makes the inverted v very much more omni directional. Not 100% omni directional but pretty close. Close enough that over the past 26 years, Iv never noticed a specific drop in RX / TX signal to a specific location (N / S or E / W). Over the past 26 years, Iv been able at one time or another to work pretty much in general all regions of the world. Which you would not be able to do if the G5RV was set up as a flat top.
ReplyDeleteYou also mentioned that the top of the V was only at 25’. The ideal minimum height should be 35’ with the ladder line dropping straight down from the top of the inverted v. Higher is better but the original design of the G5RV was found that a minimum height of 35’ helped with SWR and with the antenna resonating the TX signal better. - KD5ITM -