G5RV dipoles ?..

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prcguy

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A full size G5RV is optimized for 20m and works ok down to 80m. The half size version would be best on 10m and will work down to 40m but a little degraded from a full size 40m dipole. Since the match is only good on one band you have to be careful adding long lengths of small coax since the mismatch losses will add up fast.
prcguy
 

KD8NIV

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Ok, I was wondering how or what bands the Jr will actually do using a tuner....

Really don't have the room for the full size dipole, been trying to figure away to get one in here, but with all the power lines, don't see it happening.......
 

SCPD

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I ran a Junior one winter, and worked all all advertised bands. 40-10.
From Michigan, worked into Europe, up and down the Pacific Coast, and into Southeast Asia.
I only had it about 20' off the ground, and the ladder line was pretty much horizontal. I think because it was so low, it really was more Omni-directional.
It was just a quick little "throw up" just before November Sweepstakes.
 

prcguy

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If you only have room for the 51ft Jr version then put it up and give it a try. Try to use a low loss coax and the least amount because the match on most bands is really bad on the Jr model and coax will have additional loss when used under high VSWR conditions.

A friend of mine has a similar problem with space and uses a 50ft center fed dipole up about 25ft and fed with home made ladder line to a modified Johnson Matchbox tuner. The ladder line has very wide spacing, about 4 to 6 inches and runs to his house sitting over the tops of glass bottles he has placed on the ground.

On both 80 and 40m he puts out a similar or better signal compared to other stations at the same distance to me running much larger antennas and the key to his success is the extremely low loss feed line and tuner.
prcguy
 

AK9R

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My lot is 90 feet wide. I have a full-size 80m dipole running across the width of my lot. How could that be, you ask. Simple...I bent the dipole. The feed point is roughly at the middle of the 90 foot width of my lot. The elements go straight out to the edge of the lot and turn 90 degree for the rest of the length. The tuning is little different than a straight 80m dipole, but it works.

My point is that you may have room for that full-size G5RV if you just get a little creative about how you string it.
 

mancow

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If you only have room for the 51ft Jr version then put it up and give it a try. Try to use a low loss coax and the least amount because the match on most bands is really bad on the Jr model and coax will have additional loss when used under high VSWR conditions.

A friend of mine has a similar problem with space and uses a 50ft center fed dipole up about 25ft and fed with home made ladder line to a modified Johnson Matchbox tuner. The ladder line has very wide spacing, about 4 to 6 inches and runs to his house sitting over the tops of glass bottles he has placed on the ground.

On both 80 and 40m he puts out a similar or better signal compared to other stations at the same distance to me running much larger antennas and the key to his success is the extremely low loss feed line and tuner.
prcguy

I bet that's fun to mow over. Then again it's probably just dirt out there right?
 

prcguy

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This particular guy lives in the high desert of CA and its mostly dirt. Most of us in CA have lawns but with the water shortage here its not a good idea to have a lush green lawn with the water police looking for offenders.

I guess you could claim the need for a good RF ground under your antenna and justify keeping it moist for radio performance. I might have to try that.
prcguy



I bet that's fun to mow over. Then again it's probably just dirt out there right?
 

KD8NIV

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Any of you guys using the Optimized G5 dipole ?...

On his site says its 92ft long, ladder line is 41ft, and needs 70ft coax on it....
It would be fun trying to fi one of these in the space I have, lol....without going under the lines in the yard...like to be able to get the 80m band but at this point, not sure I could....about the only way I can get this is lay the last 20ft on the ground, because of the power lines going over head...

Been listening to my friends on 80m they sounded good on my end....
 

KD8NIV

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Been trying to figure out away to get a 92ft dipole in here, but don't see this happening....it's not so much the room for it, just what to do with the 41 ft of ladder line, then you need at least 70ft of coax to get it to work right........no trees I can use with out going under the power lines, or over them...love to be able to get the 80m band.......but looks like just going to have to go with a Jr dipole for time been ....
 

prcguy

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If your talking about the ZS6BKW, a modern computer designed version of the G5RV, I now use as my main HF antenna at home and at a remote HF radio in New England. The specs say its 94ft center fed with about 41ft of ladder line but for the dozen or so I've made they come out a little shorter like 91 to 92ft. Using insulated wire will make it even shorter.

The ZS6BKW is a good performing antenna and it has a reasonable match on all bands 40 through 6m except for 15m. With a tuner you get 15m and it also works well on 80m because its about 70% the length of a 1/2 wave dipole on 80. Since it has a good match on most bands you don't incur the additional coax loss from operating with high VSWR that the G5RV has.

If it doesn't quite fit your property you can bend the ends a bit as mentioned in another post.
prcguy


Any of you guys using the Optimized G5 dipole ?...

On his site says its 92ft long, ladder line is 41ft, and needs 70ft coax on it....
It would be fun trying to fi one of these in the space I have, lol....without going under the lines in the yard...like to be able to get the 80m band but at this point, not sure I could....about the only way I can get this is lay the last 20ft on the ground, because of the power lines going over head...

Been listening to my friends on 80m they sounded good on my end....
 

KD8NIV

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Yeah thats the one I was looking at, it says on his website its 92ft long, and has 41ft ladder line, and needs at least 70ft of coax.....

Since I dont have any trees on my lot I can use I have to set some other things to put the wire on, not sure what I can use, not sure what to do with the last 27ft of wire....then the ladder line, dont no what I can do with it, Id have about 20ft on the ground, and that 70ft of coax, well thats another thing, dont no where I can string it too, you cant just roll it up, can you?......
 

KD8NIV

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The shack is close to the hill side its on the back side of the property.....

And of course there is a telephone pole, sets on the hill, with a transformer on it, which has wires going through the back yard, and out front is another pole which has a service line on it and phone lines, all going across my trailer to the pole with the transformer on it...so, this gives me 65ft out front I can use without going under the power lines out there......

If I run this dipole a long the front of my trailer this 65ft, and bend it and cross the top of my trailer to the back yard, and back up toward my back porch, what kind of affect would it have on how it performs ?...

The Balun with the ladder line on it would be out front and about 25ft off the ground, running down a metal pipe to the ground, where I'd have 16ft on the ground, could I lay the 16ft of LL over a bush, and just go with some RG 213 coax to the shack ?.......would this cause a problem in how it performs ?..
 
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prcguy

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You have to keep the ladder line off the ground and away from metal but a few feet should be fine. I have a lot of ladder line on my roof and made stand offs by screwing a 2ft length of PVC pipe to a cinder block, then cut a slot in the PVC pipe, stick the ladder line in the slot and put a PVC pipe cap on to hold it there. I have several of these standoffs on my roof and used the same thing at my office for awhile holding the ladder line off a sheet metal roof.

You can bend and route some of the antenna wire to the side in a different direction but don't route it back towards itself. You don't specifially need 70ft of coax on this antenna but you do need a 1:1 choke balun at the ladder line and coax junction then just run the shortest length of coax to the radio and tuner.

I found with about 20ft of LMR400 I could tune all bands but 80m on my K3 with internal tuner and I added about 15ft of RG-8X and then it tuned 80m but at the expense of a little coax loss.

I would never buy one of these commercially made antennas since you can make one for the cost of some wire and ladder line.
prcguy


Yeah thats the one I was looking at, it says on his website its 92ft long, and has 41ft ladder line, and needs at least 70ft of coax.....

Since I dont have any trees on my lot I can use I have to set some other things to put the wire on, not sure what I can use, not sure what to do with the last 27ft of wire....then the ladder line, dont no what I can do with it, Id have about 20ft on the ground, and that 70ft of coax, well thats another thing, dont no where I can string it too, you cant just roll it up, can you?......
 

KD8NIV

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Alright here's what I come up with.....on the Optimized G5 dipole, I'm going to move my Imax out front and put it up 27ft and also hang the G5 on this pole using a eye, and run the ladder line and use 18" stands made of PVC pipe to keep it away from the metal pipe mast......lot of LL to leave close to the ground but will it be ok to lay it on a bush ?...

The one leg of dipole will be strung down the front side and the last 3ft will go to a pipe in the ground in a angle........ok the other leg, will be hung around my trailer to the back porch, this will be about 21ft off the ground and drop down to 12ft at my back porch......not how I'd like to hang it but about the only choice I have......for coax, have a 120ft of the LMR 400UF I'll put on it....

Will this work, will it perform very well like this ?....
 

KD8NIV

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Have a question for you guys..

I built a dipole here for the 40m band, each leg was 32.6ft, and I used 12ga solid copper insulated wire for this, and used 3/4" pvc pipe for the bones and center conn....hooked wires up and tied the ends off...height center was about 20ft and the legs was 15-17ft high.....had it hung out pretty well flat......didn't matter what I tried still wasn't able to get the swr low enough to use it.......I have metal roof, not sure if it wasn't up above the roof high enough or what, but no luck getting it to tune, this was a coax fed dipole by the way.........

My Imax, its up 21ft above the peak of the roof, and there's no swr problems with it...swr on it is a 1.1 on 10-17m....

I live in a trailer park that's where all the metal comes in to play from.....have trees but have to go under the power lines to get to them, and no trees in the yard......live on a lot which don't have much room....

Any ideas how I can hang a 40m dipole and get it to tune ?...
Have never seen swr like this that I have had this kind a trouble to get it down....
 

KD8NIV

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My 40m dipole...I mounted the dipole on the same mast pipe the Imax was on, it was about a foot below the Imax actually...sure be nice if it was somewhere else...but thats where it was and is today.

First time I hung this one up, didn't matter what I did just could not get that thing to tune, oh man this was a learning experience I won't forget, lol...so took it down and went to plan B..

Plan B, took it all down, and reworked the wire, and went with 33ft for each leg...made me a standoff by using a 14" piece of 1.5" PVC pipe, and got a U bolt and drilled holes through the PVC pipe and mounted it to the mast pipe.....I then drilled a hole in the end of the PVC pipe and used weed eater string to tie the center bone to the standoff, which is about a foot out from the mast pipe, and taped up the string so it wouldnt come loose....and taped the RG 213 coax to the standoff, and its about 8" off the mast pipe, as it goes to the ground, it don't touch anything.......

The leg out toward the driveway I hooked the shield to it, and the other leg on the hill side is the center wire.....I tried everything I thought of trying to get it to tune, but what did it was moving it out away from the metal, so today its tied off behind my neighbors trailer out there on the hill side to a tree...and its about 15ft off the ground, and about level with the center bone on the mast pipe......

The other side is 16ft off the ground as well I tried to move it out but it was in the way, so I ended up moving it back where it was from the start and just had to work with it....ended up folding back 11.5" on itself, each leg, and the swr now is on 7.0 its a 1.8.... 7.1 and 7.2 its a 1.2....7.3 have a 1.5....on 21.300 swr is a 2.5 now....I used a external swr meter while I was doing this.....it seems to talk fine, haven't had much free time to really try it out.......but this is the results I ended up with,...
 

johng1970

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A full size G5RV is optimized for 20m and works ok down to 80m. The half size version would be best on 10m and will work down to 40m but a little degraded from a full size 40m dipole. Since the match is only good on one band you have to be careful adding long lengths of small coax since the mismatch losses will add up fast.
prcguy
With a tuner, I've worked 160 meters and every band up to 6 meters!

Sent from my LG-D800 using Tapatalk
 
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