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Dipole


I'm assuming it's center-fed; how high is the center and how high are the ends?

And you don't NEED to get it down to a 1:1 SWR. That in itself is often impossible given metallic objects in the near field, type of feedline, etc. As long as the power doesn't cut back (assuming again that the radio has such a feature built in), you're good to go.
 
Not sure the height, the positive end is up top, im guessing the bottom end is to close to the house, but these are ran in attics and balconies so im not sure the issue, but im hlgonna wait till it gets warm and not so windy before I tackle it again.



I'm assuming it's center-fed; how high is the center and how high are the ends?

And you don't NEED to get it down to a 1:1 SWR. That in itself is often impossible given metallic objects in the near field, type of feedline, etc. As long as the power doesn't cut back (assuming again that the radio has such a feature built in), you're good to go.
 

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I'd see if I could find some way to bring the coax away from the feedpoint at right angles, rather than as nearly parallel as I see in the picture. That's always been a problem with "literal" vertical dipoles, and it can be a problem with sloping dipoles as well.

Weather does play a big part in antenna work, but it's always the antenna that you had to install during a tornado/sleet storm with lightning being the only light you had to work by ... :D ... it's always THAT antenna that works the best! (And there's no "positive end" to a dipole except maybe at DC).
 
try wrapping your coax into a choke, just as it leaves the feedpoint wrap a nice clean coil of 5 turns side by side on a 4.25" diameter or so piece of gray or white PVC (but never use the black ABS because it has a high carbon content) and it should help both tuning and cut down on any RFI you might otherwise end up with.
 
slope.jpg
Agree with Beetle...Loosen that coax so that it is at right angle 90* to the antenna for at least 10 or 12 ft
The bottom edge near the roof, you might try moving that away.(or above the roof line) may help also.
That coax need not be that taught that it is pulling the feedpoint down.
Not sure where you have it tuned frequency wise but...
468/27.200 = 17' 2 1/2" ft overall (8' 7" each side) is close...but the formula normally will fall in a little long maybe 5%...So 8' 2" to 8' 7" each should be close to the tuning range your shooting for. Plus remember where you separate the coax that lead length will figure into the total length. The vswr should fall in about 1.5:1...any additional tuning is meaningless at that point.
All the Best
Gary

Note: Good rule of thumb...if vswr is lower on ch.1 and higher on ch. 40 the antenna is too long
Flip side if lower on 40 than ch.1 antenna is too short...but proximity to pole/roof line and other objects with affect tuning also...Try moving it away from building or away from pole can certainly change tuning also...So you may want to try this First before adding or subtracting length.
Tune the Antenna where you use it most, do not expect it to be consistant vswr range across the entire band.
GL
 
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No quite a 90 but temporary. Hearing 38lsb aprox 100miles out oddly. Im hearing North I should get East and West.
 

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New plans: Im going to raise the current pole to 40' and put a chimney mount with a pvc pole 12' so im gonna raise it up a bit, then add another in the opposite direction. Just waiting on parts to come in.
 
No quite a 90 but temporary. Hearing 38lsb aprox 100miles out oddly. Im hearing North I should get East and West.
Not if the antenna itself doesn't think so :D. That's simply telling you that there are stations the antenna can receive to the north AT THE TIME. All antennas are different. I'd spend like a week getting used to just what characteristics it shows at the same time on several different days. Do that (and keep a log of what you find) before you make changes. THEN make just one change at a time, keeping the log going so you can see what happens when you mount it higher, or in a different direction etc. This is the learning portion of the journey.
 

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