this is driving me nuts, so now i cant sleep

ok. im about to build a multi band fan dipole (75,40,20,17,15,12,10) longest leg is 60ft'ish. now where i live I dont have alot of options to string up something.. and I can not go very high in the air (feedpoint will be about 15ft) I have powerlines that run along the property to my west so i want to stay well away from them. 1 tree is not far enough out. which leaves 1 tree left. now I can run 1 leg to the tree then run the other leg over to a stink pipe then back over to the old antenna support then back to the feedpoint... which I want to stay away from since using that path one leg will be over the roof for most of the run.

but what if i ran both legs out to the tree the legs spaced by about a ft (see image black = house, green dot = tree, red line = power line, red dot = feed point, blue lines = antenna wire) what kind of radiation pattern would this have? would I have ok results with it or would i be better off using a dummy load?

While I couldn't pretend to be very technical about this I have had a few Fan Dipoles (and I haven't met one I didn't like) and I have learned a thing or 2 about them. We regularly used one of my extra fan poles for portable events as well as field day in different arrangements.

Center (Feed) Point at 15 feet? It will work reasonably well, but not even close to one that is installed higher. You can install the legs at right angles to the other, but you can not install them side by side as indicated by the blue lines in your drawing.

I wouldn't worry about those power lines too much, and with your limitations you might be better off to consider a vertical or even a loop.

I would suggest putting it up, and then hopping on the bands using PSK and having a few QSO's. In fact, leave it [The PSK software] up and running, with the rig on, reporting what it hears to PSKReporter.

In about 2 days per band, you'll see a decent radiation pattern map on pskreporter.info :)

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Originally Posted by KA9MOT

While I couldn't pretend to be very technical about this I have had a few Fan Dipoles (and I haven't met one I didn't like) and I have learned a thing or 2 about them. We regularly used one of my extra fan poles for portable events as well as field day in different arrangements.

Center (Feed) Point at 15 feet? It will work reasonably well, but not even close to one that is installed higher. You can install the legs at right angles to the other, but you can not install them side by side as indicated by the blue lines in your drawing.

I wouldn't worry about those power lines too much, and with your limitations you might be better off to consider a vertical or even a loop.

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I had a chance for a butternut hf-9v with 160 resonator for $60.. but the 26ft tall stick got shot down real quick by the house owner.

my problem is, I get 1 pole (20ft no higher) everything else will have to be tied to a tree or something already on property. id love to tie to the trees to my east but they are not on property and well no way that guy would give me permission to tie anything off to it.

i have to keep it high enough where a truck can drive back there without pulling anything down. which leaves me 2 trees. 1 is to close the other is right distance (where blue is going) and the final 2 are IMO to close to power lines then I really want to mess with.

I can run 1 leg to the tree but it forces me having to take the other leg west tward the P-Lines to a stink pipe on the house then turning sharply back east to the wooden pole that supports my 2.4ghz wifi beam. and im not sure I can fit a 60ft leg in that short of space

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Originally Posted by KC2UGV

I would suggest putting it up, and then hopping on the bands using PSK and having a few QSO's. In fact, leave it [The PSK software] up and running, with the rig on, reporting what it hears to PSKReporter.

In about 2 days per band, you'll see a decent radiation pattern map on pskreporter.info :)

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all I would be able to do is just RX. which would work (i think on reporting)

Steve said side by side wont work.. so I may be forced to have to run 1/2 of this over the back side of the roof. zig zaged everywhere... (that should be a interesting radiation pattern)

Here's what I can say now: your plan probably won't work well. With only a foot spacing, the antenna looks like a piece of ladder line even at ten meters.

I have to think about your typical layout a bit more, but here's what I'd keep in mind:

1. Any pattern is better than no pattern.
2. For a dipole, the highest currents are at the feed point, highest voltages at the ends; get the center as high as you can.
3. You can droop the ends, but not so low that kids can touch them by mistake.
4. Try to keep the angle between the wires to 90 degrees or greater at the feedpoint to prevent excessive cancellation.

Good luck and 73,

as for spaced layout this will be the best I can reasonably do

pink = rerouted leg from other pic. going to a wood mount attached to the stink pipe (its there from where I used to have the jpole) but suddenly at that point cutting back to the east to where my 2.4ghz beam is. just not sure the 60ft leg will be all used up by then in which then I will be out of options

'IBC, I'm afraid I don't know your "living conditions" well enough to help. What kind of building is it, and how long is it? Judging from your sketch, it looks like quite a long building; can you tie off each end near the peaks of the gables, and run the antenna along the ridge?

73,

Looks like an inverted-L antenna :) Should "work".

I must be missing something: Why are you not arranging the legs as such:

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  |    \                    /
  |      \                /
  |          \            /
  |            \        /
  |              \      /
  |                \  /
  |                  V

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The feed point being the V. The | being the power line, and the / and \ being the leg(s)? And, I wouldn't try to smoosh too many bands on there. Beyond 3, it looks really ugly.

I had a similar situation one time. What I ended up doing was making a dipole for 80, then using a staple gun, I fastened the elements to the edge of the fascia around the house in opposite directions. It ended up being an L in each direction if you can picture that. I used some 24AWG. You couldn't see it, and it worked reasonably well on most bands with an antenna tuner. It was all I had to work with and I was able to get on the air.

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Originally Posted by ab1ga

'IBC, I'm afraid I don't know your "living conditions" well enough to help. What kind of building is it, and how long is it? Judging from your sketch, it looks like quite a long building; can you tie off each end near the peaks of the gables, and run the antenna along the ridge?

73,

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its a cheep modular home. I currently have a 75m coax radiator dipole up on the roof now. but the noise is awful

I basically cant have anything over 20ft in height and none of it is to be showing in the front (I get by with my arrow jpole sticking a bit over the peak but for the most parts its not noticeable unless your actually looking for it)

I live with my sister and she is overly anal about anything radio... im still amazed I was finally able to sneak some radio stuff in here. (she was the reason I lost all my shit back in 2001 when I had to move back here from NW Ind.)

UGV - im not worried about ugly to much lol. going 7 band 1/2 wave 75,40,20,17,15,12,10 (since i dont really do cw or data i left 30 out and 160 is just way to long)
as for your drawing. if it wasnt for the p-lines right by the west trees id use one of them but im not going to chance it they are just to close to the lines to be tossing rope up to the top of them not worth the risk of life. if the middle tree was about 20ft farther back it would be perfect.

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Originally Posted by K7SGJ

I had a similar situation one time. What I ended up doing was making a dipole for 80, then using a staple gun, I fastened the elements to the edge of the fascia around the house in opposite directions. It ended up being an L in each direction if you can picture that. I used some 24AWG. You couldn't see it, and it worked reasonably well on most bands with an antenna tuner. It was all I had to work with and I was able to get on the air.

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yea right now I have a 75 dipole laying on the roof (made of rg-59 75ohm) 3.9mhz its 1.1 without tuner. but i just pick up way to much noise I can use the tuner to get 1.1 on 7.2mhz but I RFI the hell out of things in the house... (RFI issues will = me not able to have radio) if the damn house was oriented north-south. in this lot. id be in heaven (house just fits on the lot east-west by inches its so close to being over property lines.

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Originally Posted by W2IBC

its a cheep modular home. I currently have a 75m coax radiator dipole up on the roof now. but the noise is awful

I basically cant have anything over 20ft in height and none of it is to be showing in the front (I get by with my arrow jpole sticking a bit over the peak but for the most parts its not noticeable unless your actually looking for it)

I live with my sister and she is overly anal about anything radio... im still amazed I was finally able to sneak some radio stuff in here. (she was the reason I lost all my shit back in 2001 when I had to move back here from NW Ind.)

UGV - im not worried about ugly to much lol. going 7 band 1/2 wave 75,40,20,17,15,12,10 (since i dont really do cw or data i left 30 out and 160 is just way to long)
as for your drawing. if it wasnt for the p-lines right by the west trees id use one of them but im not going to chance it they are just to close to the lines to be tossing rope up to the top of them not worth the risk of life. if the middle tree was about 20ft farther back it would be perfect.

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Well, the power lines are 20 ft up or so, correct? Then ends of the legs will be lower. You can tie them off to pretty much anything.

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Originally Posted by KC2UGV

Well, the power lines are 20 ft up or so, correct? Then ends of the legs will be lower. You can tie them off to pretty much anything.

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if i end up dead im going to haunt you. lol

Do you have a good tuner?

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Originally Posted by W2IBC

if i end up dead im going to haunt you. lol

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What I'm saying is you wont need to toss rope over the power lines. Just run under it. If it looks like you're going to contact, then stop obviously.

Don't want to play with the triple wires in the air :)

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Originally Posted by W2IBC

I basically cant have anything over 20ft in height and none of it is to be showing in the front (I get by with my arrow jpole sticking a bit over the peak but for the most parts its not noticeable unless your actually looking for it)

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Sounds like an HOA to me. Deed restrictions?

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I live with my sister and she is overly anal about anything radio....

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From what standpoint? Interference? The higher and further away the antenna, the less interference you'll have.

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Originally Posted by KJ3N

Sounds like an HOA to me. Deed restrictions?



From what standpoint? Interference? The higher and further away the antenna, the less interference you'll have.

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she hates radio shit always has

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Originally Posted by W2IBC

she hates radio shit always has

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Tell her to start hating her cell phone, then. :omg: :rofl:

Does she wear tin foil hats? :nuts:

If you have a tuner, you could always build a end fed longwire...... Easy to hide and you could snake it to where ever you needed it to go. Here is one to consider: ---> http://www.wa0itp.com/longwire.html

I was thinking the drawing you posted would be more like a feedline except at a couple of 10 and 12m frequencies. Just a guess.
You may be limited to a windowline J-pole for 10m. You could build one for 17 and another for 20 and string them up in the trees.
It's hard to really say without being onsite etc etc.

Lost all your stuff in 2001 because of anal radio sis? WTH did she do? Give it to Goodwill? If you'd rather not say, I understand. I'm just curious about what people do and what goes through their mind when they are so RELIGIOUSLY dead set against something, especially when it's radio.
When I was growing up, I had to start hiding radios away from my parents because who the hell needs more than one radio? Right?
Turns out a distant uncle was a Zenith dealer in N. Africa when the Trans Oceanic was big in the 40s and 50s. This uncle ran a shop and charged batteries (for a price) for customers. The claim was that he was taking the good batteries from new radios the first time they came in for a charge and gave the farmers and other people who had to save for a couple of years to buy a radio in the first place, bad batteries that had to be charged much more often while selling off the nearly new batteries that he got for free to the police and military. So as far as my parents were concerned, radio was dirty.

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Originally Posted by KG4CGC

I was thinking the drawing you posted would be more like a feedline except at a couple of 10 and 12m frequencies. Just a guess.
You may be limited to a windowline J-pole for 10m. You could build one for 17 and another for 20 and string them up in the trees.
It's hard to really say without being onsite etc etc.

Lost all your stuff in 2001 because of anal radio sis? WTH did she do? Give it to Goodwill? If you'd rather not say, I understand. I'm just curious about what people do and what goes through their mind when they are so RELIGIOUSLY dead set against something, especially when it's radio.

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Talking on the air be da work of da debil!:yes:

well I got a whole jumpble of wires up... tried to do the fan, but couldnt keep the shit from tangling up super bad even with spacers.. so fuck I give up.

edit 19:09 - well it works well on 40 it seems got a 5/9 in WI and PA. 75 loads up above 3930 but no luck even with a tuner below that did get a 5/6 down to TN on 3980

Why not just built an inverted vee and use balanced feed line instead of coax. (You can even use TV old fashioned twin lead). Cut the vee for the lowest band you intend to use. Get the feed point up as high as you can and run the balanced line into your station. Then use a tuned (pref a link coupled type) between your transmitter (radios) and the antenna. You should be able to tune up on every band. I used this set up for years and it gave me excellent results. Mine was cut for 75 metres and it worked great on 75, 40, 20, 15 and 10. Nice thing is that if you build it right it is almost invisible. Most people would never notice it.

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Originally Posted by W2IBC

well I got a whole jumpble of wires up... tried to do the fan, but couldnt keep the shit from tangling up super bad even with spacers.. so fuck I give up.

edit 19:09 - well it works well on 40 it seems got a 5/9 in WI and PA. 75 loads up above 3930 but no luck even with a tuner below that did get a 5/6 down to TN on 3980

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I tried building a 5 band parallel dipole years ago, fed with coax into a 1-1 balun. Interaction between the wires made it impossible to tune all the bands. However, For many years I have had a two band inverted parallel dipole here cut for 40 and 75 meters. Low SWR on both bands. Don't even need a tuner.

I had a Fan Dipole with wires cut for 75M, 40M and 20M. I used plastic coat hangers for seperators. It worked like gangbusters for all 3 bands with-out a tuner and everywhere else with the tuner........ I even made a few contacts on 160M and 6M. I could never get it to work on 60M.... I don't know why.

Another one I built I used PVC Pipe cut to length for my separators....... for some reason, that antenna sucked..... :dunno:

yea wierd how these things work... or not work.

my whole deal got ripped down anyway, so for now im stuck with just a indoor 20m dipole.

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Originally Posted by n2ize

Why not just built an inverted vee and use balanced feed line instead of coax. (You can even use TV old fashioned twin lead). Cut the vee for the lowest band you intend to use. Get the feed point up as high as you can and run the balanced line into your station. Then use a tuned (pref a link coupled type) between your transmitter (radios) and the antenna. You should be able to tune up on every band. I used this set up for years and it gave me excellent results. Mine was cut for 75 metres and it worked great on 75, 40, 20, 15 and 10. Nice thing is that if you build it right it is almost invisible. Most people would never notice it.

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Just be careful though, at higher frequencies the nulls get pretty sharp. My last inverted vee cut for 80m had a deep null towards Europe on 20m. Therefore it was a terrible DX and contest antenna for me.

My current vee is on the ground, The snow of October took it away.

Have you thought of an off center fed dipole? It might not be as good as a fan, but it will be easier to get in the air with out becoming a birds nest..

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Originally Posted by N2RJ

Just be careful though, at higher frequencies the nulls get pretty sharp. My last inverted vee cut for 80m had a deep null towards Europe on 20m. Therefore it was a terrible DX and contest antenna for me.

My current vee is on the ground, The snow of October took it away.

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Must have something to do with how it was oriented. My 134 foot long dipole works fantastic into Europe on 20m. It runs almost dead on N/S. I have a deep null into the West Coast, so I use the 40m loop for that.

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Originally Posted by KA9MOT

I had a Fan Dipole with wires cut for 75M, 40M and 20M. I used plastic coat hangers for seperators. It worked like gangbusters for all 3 bands with-out a tuner and everywhere else with the tuner........ I even made a few contacts on 160M and 6M. I could never get it to work on 60M.... I don't know why.

Another one I built I used PVC Pipe cut to length for my separators....... for some reason, that antenna sucked..... :dunno:

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Did you take out the sprinkler heads?

I left the coats on the hangers too! :rofl:

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Originally Posted by KA9MOT

I left the coats on the hangers too! :rofl:

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I'm sure that's the reason it performed so well. Acted as a thermal blanket to keep the SWR's inside the wire.

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Originally Posted by KJ3N

Must have something to do with how it was oriented. My 134 foot long dipole works fantastic into Europe on 20m. It runs almost dead on N/S. I have a deep null into the West Coast, so I use the 40m loop for that.

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Yep, that was the problem. But I had no choice since the only supports I could use were in certain directions.

Now it's a moot point since I have a tower, beam and other antenna supports to play with.