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cliffhanger
04-17-2017, 06:54 PM
I am located in a small valley in southwestern oregon surrounded be 1200 ft hills on all sides. what type of antenna would be best for working dx.I currently am using a sirio 5/8 with ground plane. Have a ham4 rotor and a 36 ft power pole to mount a directional antenna on. The sirio works great in this little valley but altho i can hear dx i can't reach out to them. My radio is a Galaxy dx 2547 and a xforce 350 booster.My present antenna is about 22 ft off the ground. Any suggestions for a better antenna? I have a 11 meter moxom but i haven't put it up to try . I'm 75 and i'd like to get it right the first time.

222DBFL
04-17-2017, 07:02 PM
Get your current antenna up higher and you'll have better luck. A moxon is a great antenna for DX as well a most beam antennas. I use a Siri vector 4000 and I have no problem getting my name called with 100 watts!! Conditions play into things, but having a good antenna setup helps a lot!! Coax, connectors, surge arrestors, and such are needed and need to be good stuff!
But in your case, getting that antenna up to at least 30ft or more will help believe it or not. Hope this helps. Have a good one. And again, a good DX antenna is a 3 element beam. Set it up right and it will do the job! But try what I said and move your current antenna up as high as you can. See what happens. It's the cheapest way to go! And DX is pretty dead as well on 11 meters. So you aren't missing much of anything!!

cliffhanger
04-17-2017, 07:36 PM
Thanks i'll put the moxom or some kind of beam on top of the 36ft on the rotor. Are the quads equal or better at getting out dx than the 3 element beans. The sirio covers this local very well at 24ft. This little valley is only about 1 square mile but the hills are all round. I hope to only do this once?

222DBFL
04-17-2017, 09:58 PM
Quads can be better. But they will require much more maintenance than a 3 element beam will. Or even a moxon for that matter. Both will work well. And a quad would work well. But like I said, requires much more maintaining. JMHO's.

Jay Mojave
04-18-2017, 07:47 AM
Hello Cliffhanger: Suggest you check your SWR and output power before any antenna modifications or additions and such are done. The 5/8 wavelength antenna and amp should allow you to shoot some skip. Remember the skip conditions are pretty bad right now.

To high of a SWR may indicate something wrong with the antenna. Water in the coax will cause a lot of loss in the output power and received signals, and the SWR will look great because the higher loss in the coax will get less power to the antenna, and much less power reflected. This can be checked by measuring the power out from the radio/amp then measuring the power at the end of the coax, for a 100 FT of coax should be approx. ballpark .7 to 1 dB which is 20% or less.

A Antenna not properly assembled and high SWR will throw you a curve also.

Jay in the Great Mojave Desert

cliffhanger
04-19-2017, 09:22 AM
SWR is 1.0 -1.2 across the band. Checked all the connections and they are fine. I know the importance of every thing being water tight. Will add another ground rod to be sure of ground. Would like to stick with a vertical antenna but would go with a beam of some type if i have to. Would the sirio nv4k be better than the 5/8 sirio i'm now running? I will also raise the antenna up to at least 30+ feet. I have the rotator and a mjf 15 meter moxon which is easy to cut down for 11 meter operation. This moxom is still in the box so if i don't use it or the rotor i would sell them. I know it's hard to answer what i am asking. Biggest problem is the valley and hills. thanks

222DBFL
04-19-2017, 09:58 PM
If you raise the antenna you have now you should notice a difference. Your take off angle will change as you raise your antenna. I would try what you have for now as like I said, the 11 meter band is about dead as a door nail!! Only the occasional DX these days. Just my experience. I wouldn't go spending a bunch on antennas at the moment, but that is just me. Like I said, raise the antenna up you have now before going out and getting another antenna. You will be surprised at what raising your antenna 10-15ft from it current height will do. Again, JMHO's and my experience. Hope this helps.

222DBFL
04-20-2017, 05:04 AM
Also to reply about the Sirio vector 4000, or what you called the NV4K is a tall antenna coming in at nearly 28ft long total length. And they are great antennas if, and I mean if, you don't live in an area the gets hit with heavy winds a lot, as the antenna will bend quite a bit and is prone to failure at that point. If you don't get a lot of wind or bad weather, then you'll be fine. Mine handled some rough storms here around central FL. I took it down for the last hurricane that got us where I live and I am glad I did as I still have an antenna!! Just haven't put it back on my new push up pole and raise it up to 30-35ft. It was at 27ft to the base last tone up, and it talked very well locally, out to 60-70 miles about daily, and for DX it worked great. I also have a horizontal dipole up at about 40ft high or maybe a little more, and it works well when the vertical doesn't pick some people up due to noise. That is one thing about a beam and placing it horizontal, you normally don't have a lot of noise!! Anyways. Just my experiences with the antennas I use. To be honest I don't think you're going to notice any big change in receive or transmit by changing to the NV4K. Unless you have a crappy install, which I don't think you do at all!! And I just don't think the difference in RX/TX will be much different. Getting the antenna you have now up as high as you can safely is the way to go for now. Also maybe try a inverted V or horizontal Dipole. Dr. Dipole on Ebay sells a pretty good one with the 1:1 matching balun. They work well! Or just make one yourself. Instructions are all over the good old interweb!! Let us know how you make it and what you ended up doing. Be safe and good luck!!

cliffhanger
04-20-2017, 10:23 AM
Called the local electric company about a used power pole. They said to come in and see what they had in the yard. They charge $1 flat fee for any pole they have. My neighbor in the road building business said he could get it home for me. I will get the longest one i can. They said they run between 30 and 50 ft. Plan now is to put the moxom on the pole and sirio without the ground planes a few feet above the moxom. Would like to make a lay-down bracket for the antenna mast and a pulley system on top of the pole so i could lower the mast without climbing the pole. I have access to a machine shop so lay-down bracket would be an easy build. Thanks for the ideas, now have a plan. Any other suggestions will be appreciated. Will take pictures as i go. Thanks

222DBFL
04-20-2017, 08:21 PM
Keep the ground planes radials on the sirio antenna as they are needed for matching purposes. Removing them will make the antenna most likely impossible to tune properly. Just some food for thought. Try one antenna at a time and then add the 2nd one and see how it works. But like I said, do r remove the GP radials from the 5/8th wave antenna you have. Good luck and be safe!!