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Large Wire Antenna for 17m
I have some space and some high trees. I already use a 400ft doublet with
atu for several bands and a 30m half square and get good results. I want to improve my performance on 17m. I am now thinking about a wire antenna with reasonable performance for 17m only. I have thought about a full wave loop, even a bobtail. A broadside array would be great but I am not keen on antennas with reflectors or directors because of the complexity of support ropes. So, really some kind of antenna supported by ropes from two trees would be ideal. Any ideas please? Alan VK6BN |
Large Wire Antenna for 17m
The problem you'll run smack into with any fixed antenna is that to get
gain in one direction you've got to take away gain in others. So the first thing you have to decide is which directions do you want to improve your signal in, and which are you willing to sacrifice. Then consider where your trees are. Only then can you begin to consider what kind of antenna might deliver what you want. Roy Lewallen, W7EL Alan Taylor wrote: I have some space and some high trees. I already use a 400ft doublet with atu for several bands and a 30m half square and get good results. I want to improve my performance on 17m. I am now thinking about a wire antenna with reasonable performance for 17m only. I have thought about a full wave loop, even a bobtail. A broadside array would be great but I am not keen on antennas with reflectors or directors because of the complexity of support ropes. So, really some kind of antenna supported by ropes from two trees would be ideal. Any ideas please? Alan VK6BN |
Large Wire Antenna for 17m
Thanks Roy,
I should have mentioned the trees are in position for a broadside array to fire in the (two) directions I need. I would use the trees that currently support the 30m half square firing NE/SW. 73 Alan "Roy Lewallen" wrote in message ... The problem you'll run smack into with any fixed antenna is that to get gain in one direction you've got to take away gain in others. So the first thing you have to decide is which directions do you want to improve your signal in, and which are you willing to sacrifice. Then consider where your trees are. Only then can you begin to consider what kind of antenna might deliver what you want. Roy Lewallen, W7EL Alan Taylor wrote: I have some space and some high trees. I already use a 400ft doublet with atu for several bands and a 30m half square and get good results. I want to improve my performance on 17m. I am now thinking about a wire antenna with reasonable performance for 17m only. I have thought about a full wave loop, even a bobtail. A broadside array would be great but I am not keen on antennas with reflectors or directors because of the complexity of support ropes. So, really some kind of antenna supported by ropes from two trees would be ideal. Any ideas please? Alan VK6BN |
Large Wire Antenna for 17m
Roy, ruling out quad loops and multi element antennas what do we have
available? I like the idea of working both LP and SP to the US but if you have an idea for a wire antenna supported by only two ropes I would consider that. What would the pattern be like for a bobtail with extra vertical elements spaced the usual half wave? With the trees I have in mind I could possibly fit in six vertical elements. Thanks es 73 Alan "Roy Lewallen" wrote in message ... The problem you'll run smack into with any fixed antenna is that to get gain in one direction you've got to take away gain in others. So the first thing you have to decide is which directions do you want to improve your signal in, and which are you willing to sacrifice. Then consider where your trees are. Only then can you begin to consider what kind of antenna might deliver what you want. Roy Lewallen, W7EL Alan Taylor wrote: I have some space and some high trees. I already use a 400ft doublet with atu for several bands and a 30m half square and get good results. I want to improve my performance on 17m. I am now thinking about a wire antenna with reasonable performance for 17m only. I have thought about a full wave loop, even a bobtail. A broadside array would be great but I am not keen on antennas with reflectors or directors because of the complexity of support ropes. So, really some kind of antenna supported by ropes from two trees would be ideal. Any ideas please? Alan VK6BN |
Large Wire Antenna for 17m
Alan Taylor wrote:
I have some space and some high trees. I already use a 400ft doublet with atu for several bands and a 30m half square and get good results. I want to improve my performance on 17m. I am now thinking about a wire antenna with reasonable performance for 17m only. I have thought about a full wave loop, even a bobtail. A broadside array would be great but I am not keen on antennas with reflectors or directors because of the complexity of support ropes. So, really some kind of antenna supported by ropes from two trees would be ideal. Any ideas please? Alan VK6BN Hi Alan, you do not say how High you can get your antenna in the air.. but if you have the room and the height a Sterba Curtain may be a solution. 73 Dave Kc1di |
Large Wire Antenna for 17m
Since you are supporting a 30 meter vertical, I suspect that you can
support a 17 meter half wave vertical.. A halfwave, bottom fed, monopole, worked against an elevated counterpoise... Said elevated counterpoise to be a half wave in length, and tapped at it's centerpoint... Two or three feet off the ground will work, while head high would be nice... A single antenna will give 360 coverage... Two, three, or four of these with switching to rotate the pattern will give you gain in given directions, while still allowing 360 coverage... denny / k8do Alan Taylor wrote: Roy, ruling out quad loops and multi element antennas what do we have available? Thanks es 73 Alan |
Large Wire Antenna for 17m
Alan Taylor wrote:
I have some space and some high trees. I already use a 400ft doublet with atu for several bands and a 30m half square and get good results. I want to improve my performance on 17m. I am now thinking about a wire antenna with reasonable performance for 17m only. I have thought about a full wave loop, even a bobtail. A broadside array would be great but I am not keen on antennas with reflectors or directors because of the complexity of support ropes. So, really some kind of antenna supported by ropes from two trees would be ideal. Any ideas please? Omnidirectional or directional? -- 73, Cecil http://www.w5dxp.com |
Large Wire Antenna for 17m
Alan Taylor wrote:
I should have mentioned the trees are in position for a broadside array to fire in the (two) directions I need. A horizontal 66 ft. dipole fed with ladder-line would work for 40m-10m and give you some gain over a 1/2WL dipole on 17m where it would be an Extended Double Zepp. EZNEC says feeding it with 9 feet of 450 ohm ladder-line and then coax the rest of the way gives a pretty good single-band match on 17m. -- 73, Cecil http://www.w5dxp.com |
Large Wire Antenna for 17m
I have some space and some high trees. I already use a 400ft doublet with
atu for several bands and a 30m half square and get good results. I want to improve my performance on 17m. I am now thinking about a wire antenna with reasonable performance for 17m only. I have thought about a full wave loop, even a bobtail. A broadside array would be great but I am not keen on antennas with reflectors or directors because of the complexity of support ropes. So, really some kind of antenna supported by ropes from two trees would be ideal. Any ideas please? As others have said, you need to decide where you want to point it first, because something with significant gain is going to be directional. For 17m you probably want to go horizontally polarized if you have high trees. You might consider a horizontal vee beam, the lengths and enclosed angled are relatively non-critical. It would also work well on 20 and 15m. I have also constructed tree-supported yagis (wire) and quads, but you do need to tune the parasitic elements carefully to get good performance. Two triangular quad elements (flat side up, fed at bottom point) separated by three PVC pipe spacers makes a nice quad that will hang between only two supports. I used to have a couple of those up for 20m and 15m. Tor N4OGW |
Large Wire Antenna for 17m
If you can get it high enough, and I assume you can, why not a Delta loop
with the apex at the bottom? I have tried several different 17 meter antennas, but the Delta loop is the best I found. True, it is only bi-directional, but mine is NE/SW and works pretty well in those directions. I use a Sigma 5 vertical dipole for everything else, but the loop is better that the vertical in it's favored directions by a lot. I also used a half square on 30 meters, but have since removed it in favor of a simple inverted vee. I found the half square, while very effective on transmitting, was noisy on receive. The vee 'heard' things better and seems just as effective on transmitting. Fortunately, I was able to get the vee's apex up to 45 feet. Anything lower than that favors the half square on 30. I mention this because I also tried a half square on 17, but the loop was MUCH better. -- Jim Bob Buckeye AKA **** Jim Leder**** K8CXM since 1961 IBM retiree since 1999 http://home.fuse.net/k8cxm/ "Alan Taylor" wrote in message ... I have some space and some high trees. I already use a 400ft doublet with atu for several bands and a 30m half square and get good results. I want to improve my performance on 17m. I am now thinking about a wire antenna with reasonable performance for 17m only. I have thought about a full wave loop, even a bobtail. A broadside array would be great but I am not keen on antennas with reflectors or directors because of the complexity of support ropes. So, really some kind of antenna supported by ropes from two trees would be ideal. Any ideas please? Alan VK6BN |
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