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#1
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Spacecraft antennae
In dealing with zonal restrictions (Yank) and planning
permission (Brit) I wonder if there could be a way round these limitations by emulating the antennae of spacecraft, by which I mean ingenious ways to fold the whole thing up when not in use? (OK, I do understand that with spacecraft it is a one-way operation of only unfolding.) There have been designs published in Brit of using the steel of wind-up tape measures, and this could be a potential starting point for any discussion, by the use of flat metal tape. (I did have once a hi power ATU that tuned the inductor by winding a flat tape around a metallic drum.) What I would envisage, although I do not have either the mechanical or the mental wherewithal at the moment would be a telescopic arrangement that compressed down to about 6 feet, but when fully opened out (Perhaps as a flower unfolds from a bud?) would be a 30 foot mast with the equivalent of a TA33Jr atop. A worthwhile challenge or just another of my pipe dreams (Vapourware as they have been unkindly christened in another NG)? |
#2
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QST
In article ,
"gareth" wrote: In dealing with zonal restrictions (Yank) and planning permission (Brit) I wonder if there could be a way round these limitations by emulating the antennae of spacecraft, by which I mean ingenious ways to fold the whole thing up when not in use? (OK, I do understand that with spacecraft it is a one-way operation of only unfolding.) There have been designs published in Brit of using the steel of wind-up tape measures, and this could be a potential starting point for any discussion, by the use of flat metal tape. (I did have once a hi power ATU that tuned the inductor by winding a flat tape around a metallic drum.) What I would envisage, although I do not have either the mechanical or the mental wherewithal at the moment would be a telescopic arrangement that compressed down to about 6 feet, but when fully opened out (Perhaps as a flower unfolds from a bud?) would be a 30 foot mast with the equivalent of a TA33Jr atop. A worthwhile challenge or just another of my pipe dreams (Vapourware as they have been unkindly christened in another NG)? Gareth- You do believe in aiming high! You may not end up with a TA33Jr, but might find something else that works almost as well. My approach is the "Octopus" antenna that was published in QST magazine several years ago. It is a fan dipole made out of mobile whips mounted on an electrical box. It just fits in my attic. It does not work well on the lower frequencies, but I'm making lots of contacts on the higher bands. Speaking of tape measures, I have an old mil-surplus Hy-Gain Tape Dipole. Two versions are described at http://www.n2ckh.com/HA4000.htm. Also, for VHF and higher frequencies, spacecraft and aircraft often use "patch" antennas that are mere lumps on their skin! Fred K4DII |
#3
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QST
"Fred McKenzie" wrote in message
... Speaking of tape measures, I have an old mil-surplus Hy-Gain Tape Dipole. Two versions are described at http://www.n2ckh.com/HA4000.htm. That's very interesting and also proving that there is nothing new under the Sun! I'll need to google for the Octopus, though |
#4
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QST
"gareth" wrote in message
... "Fred McKenzie" wrote in message ... Speaking of tape measures, I have an old mil-surplus Hy-Gain Tape Dipole. Two versions are described at http://www.n2ckh.com/HA4000.htm. That's very interesting and also proving that there is nothing new under the Sun! I'll need to google for the Octopus, though OK, found this .. http://kc5our.com/wordpress/wp-conte...entation-1.pdf |
#5
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QST
"gareth" wrote in message
... "gareth" wrote in message ... "Fred McKenzie" wrote in message ... Speaking of tape measures, I have an old mil-surplus Hy-Gain Tape Dipole. Two versions are described at http://www.n2ckh.com/HA4000.htm. That's very interesting and also proving that there is nothing new under the Sun! I'll need to google for the Octopus, though OK, found this .. http://kc5our.com/wordpress/wp-conte...entation-1.pdf Bad practice to repsond to my own posts, but is a Hamstick merely a plastic tube with a loading coil wound around it, and then a whip antenna at one end? (I have on my desk plans to make a coil winding machine) |
#6
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Spacecraft antennae
On Tue, 26 Aug 2014 11:35:47 +0100, "gareth"
wrote: I wonder if there could be a way round these limitations by emulating the antennae of spacecraft, by which I mean ingenious ways to fold the whole thing up when not in use? I've been working on inflatable antennas and towers for several years. Unfortunately, I don't have much to show for my efforts. Maybe by next Field Day. This is the current incantation of Bosch Aerospace: http://www.ltaprojects.com https://www.youtube.com/channel/UC8cxVcsOmrXv1d4aNaXoQCw They sell on eBay. For wire antennas, you might look into a tethered aerostat: https://www.google.com/search?q=aerostat&tbm=isch Just one problem... vertical HF antennas are not the best because of the grounding requirements. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
#7
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QST
In article ,
"gareth" wrote: "gareth" wrote in message ... "gareth" wrote in message ... "Fred McKenzie" wrote in message ... Speaking of tape measures, I have an old mil-surplus Hy-Gain Tape Dipole. Two versions are described at http://www.n2ckh.com/HA4000.htm. That's very interesting and also proving that there is nothing new under the Sun! I'll need to google for the Octopus, though OK, found this .. http://kc5our.com/wordpress/wp-conte...-Antenna-Prese ntation-1.pdf Bad practice to repsond to my own posts, but is a Hamstick merely a plastic tube with a loading coil wound around it, and then a whip antenna at one end? (I have on my desk plans to make a coil winding machine) Gareth- I replied to your message titled, "Spacecraft antennae". I do not know how my reply became a new message titled, "QST". That article on the Octopus Antenna is interesting. It is essentially the same antenna described in QST, but construction is slightly different. I suppose mine is a little different as well. For example, I added a place for a vertical whip. I currently use a 4 foot vertical whip to add a fifth band (10 Meters). The ground whip for 20 Meters is a Hustler mast with the kit for extra resonators. I use a 20 Meter resonator plus a 10 Meter resonator to balance the vertical whip. The 4 foot vertical whip fits in the attic with an inch to spare. Even though it does not have whips for 12 or 17 Meters, it can be matched with an LDG tuner. When those bands are open, I make contacts! I believe your description of the Hamstick is correct. Fred K4DII |
#8
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QST
Fred McKenzie wrote in news:fmmck-
: I replied to your message titled, "Spacecraft antennae". I do not know how my reply became a new message titled, "QST". Xnews shows it in the same thread, depending on its thread ID or whatever it's called. Maybe your client sorts only by subject title, though it might have the option to do otherwise. |
#9
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QST
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#10
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QST
On 8/28/2014 8:02 AM, Lostgallifreyan wrote:
Fred McKenzie wrote in news:fmmck- : I replied to your message titled, "Spacecraft antennae". I do not know how my reply became a new message titled, "QST". I just found another explanation. Ò^O In Xnews, when I replied just now, I forgot to refresh before looking in another group this thread is crossposted to. My reply showed up there, and not here, because that group was the first one I saw the post in! It won't now appear here (for me) unless I fiddle about with Xnews to make it so. Your message shows up just fine in both newsgroups. -- ================== Remove the "x" from my email address Jerry, AI0K ================== |
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