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#1
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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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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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"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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"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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"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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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 |
#7
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![]() "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 I agree with Fred that while wanting a beam at a decent height, there may be some acceptable lower performance alternatives. At least you could use some of those while still pursuing the optimum. I've had good luck with an attic loop antenna strung around the rafters and fed with a tuner. I haven't had a loop large enough to use on 40 and below, but it worked fine on 20 and above. Currently, I use a 14 foot whip mounted on top of a rather large metal patio cover. It is fed with about 20 feed of RG-8 and a tuner. Performance is not bad on 20 and above. I can manually insert a coil to use it on 40 or 80. It is "ok" on 40 and not so good on 80. I have a friend who uses a Butternut vertical. It is on a tilt base, and he keeps it lowered when not in use. His homeowner association has agreed to that arrangement because it is considered "temporary" instead of permanent. Good luck. |
#8
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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 |
#9
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"gareth" wrote in news:lthnu9$ilc$1@dont-
email.me: There have been designs published in Brit of using the steel of wind-up tape measures, and this could be a potential starting point for any discussion, by the use of flat metal tape. I suspect my notion is not new, but what about a coil of wire, some well- spaced trees, a long lanyard, a tennis ball, and a spud gun? Someone will likely have one they prepared earlier, so I won't put the bits together. ![]() |
#10
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"Lostgallifreyan" wrote in message
. .. "gareth" wrote in news:lthnu9$ilc$1@dont- email.me: 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 suspect my notion is not new, but what about a coil of wire, some well- spaced trees, a long lanyard, a tennis ball, and a spud gun? Someone will likely have one they prepared earlier, so I won't put the bits together. ![]() A well-tried and tested solution to one problem, but I'd be interested in a structure that when you go QRT, you could then retract it back. |
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