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Antenna Launcher
There is an artical by W4SSY in the March 2009 QST Magazine. I am
planning to duplicate it for use at my QTH. I am interested in any comments, especially from anyone who may have already built one. My available trees may be about 80 feet so that is my minimum expectations! There is a lot of Google information available but I am trying to focus on this example. John Ferrell W8CCW |
Antenna Launcher
On Nov 27, 11:27�am, John Ferrell wrote:
There is an artical by W4SSY in the March 2009 QST Magazine. I am planning to duplicate it for use at my QTH. I am interested in any comments, especially from anyone who may have already built one. My available trees may be about 80 feet so that is my minimum expectations! There is a lot of Google information available but I am trying to focus on this example. John Ferrell W8CCW Hi John, I have not built one yet but am contemplating. Mine will use a Rain Bird 1" Auto Sprinkler Valve, electrically actuated (24 VAC or DC). I plan to use a Harbor Freigth 5 in one power source for the air compressor, the pressure gage, and the 24 VAC actuator supply. The power source is $60-$90 depending on the sale going on, it is also handy for lots of other stuff. This will be my first shot because I have this available. As far as the PVC, tire valve, fishing reel, ect. don't have that much experience. As far as line, I have had one break on me after a nice launch with a sling shot. Make sure your line is of good quality. Happy launching. Gary N4AST |
Antenna Launcher
On Fri, 27 Nov 2009 17:13:50 -0800 (PST), Gary
wrote: On Nov 27, 11:27?am, John Ferrell wrote: There is an artical by W4SSY in the March 2009 QST Magazine. I am planning to duplicate it for use at my QTH. I am interested in any comments, especially from anyone who may have already built one. My available trees may be about 80 feet so that is my minimum expectations! There is a lot of Google information available but I am trying to focus on this example. John Ferrell W8CCW Hi John, I have not built one yet but am contemplating. Mine will use a Rain Bird 1" Auto Sprinkler Valve, electrically actuated (24 VAC or DC). I plan to use a Harbor Freigth 5 in one power source for the air compressor, the pressure gage, and the 24 VAC actuator supply. The power source is $60-$90 depending on the sale going on, it is also handy for lots of other stuff. This will be my first shot because I have this available. As far as the PVC, tire valve, fishing reel, ect. don't have that much experience. As far as line, I have had one break on me after a nice launch with a sling shot. Make sure your line is of good quality. Happy launching. Gary N4AST I bought most of the supplies last night at Home Depot. The Orbit sprinkler valve was only about $12. It is an inline type valve like the one in the artical. I was thinking I would use a long piece of pipe as the accumulator but after doing the math I have decided to go back and get a piece of 3 inch pipe to use. BTW, the cement and primer is available in a single package for about $6.50. I am a little concerned about the loose fit of the projectile in the 1-1/2 inch barrel. I will report back as I continue. John Ferrell W8CCW |
Antenna Launcher
On Nov 28, 10:45�am, John Ferrell wrote:
On Fri, 27 Nov 2009 17:13:50 -0800 (PST), Gary wrote: On Nov 27, 11:27?am, John Ferrell wrote: There is an artical by W4SSY in the March 2009 QST Magazine. I am planning to duplicate it for use at my QTH. I am interested in any comments, especially from anyone who may have already built one. My available trees may be about 80 feet so that is my minimum expectations! There is a lot of Google information available but I am trying to focus on this example. John Ferrell W8CCW Hi John, �I have not built one yet but am contemplating. �Mine will use a Rain Bird 1" Auto Sprinkler Valve, electrically actuated (24 VAC or DC). �I plan to use a Harbor Freigth 5 in one power source for the air compressor, the pressure gage, and the 24 VAC actuator supply. The power source is $60-$90 depending on the sale going on, it is also handy for lots of other stuff. This will be my first shot because I have this available. �As far as the PVC, tire valve, fishing reel, ect. don't have that much experience. �As far as line, I have had one break on me after a nice launch with a sling shot. �Make sure your line is of good quality. Happy launching. Gary N4AST I bought most of the supplies last night at Home Depot. The Orbit sprinkler valve was only about $12. It is an inline type valve like the one in the artical. I was thinking I would use a long piece of pipe as the accumulator but after doing the math I have decided to go back and get a piece of 3 inch pipe to use. BTW, the cement and primer is available in a single package for about $6.50. I am a little concerned about the loose fit of the projectile in the 1-1/2 inch barrel. I will report back as I continue. John Ferrell W8CCW- Hide quoted text - - Show quoted text - I am sure you saw when Goggling that many use a Tennis ball with pennies stuffed inside for weigth. That is what I intend to try, will take a bit larger barrel than the one in the article. The tennis ball will cause less damage if it comes down on a car window, or someones head! Be interested to hear how yours works. Gary N4AST |
Antenna Launcher
The pipe for the barrel is 1 1/4 in. 24 in. long. The end caps for the
projectile are 3/4 in. so there is not to much of a loose fit. I haven't made one myself but a friend of mine has & it does just like the article say's, use with caution & safety. I'm interested how it works with a tennis ball, that sounds real neat. Howard K0ACF "John Ferrell" wrote in message ... On Fri, 27 Nov 2009 17:13:50 -0800 (PST), Gary wrote: On Nov 27, 11:27?am, John Ferrell wrote: There is an artical by W4SSY in the March 2009 QST Magazine. I am planning to duplicate it for use at my QTH. I am interested in any comments, especially from anyone who may have already built one. My available trees may be about 80 feet so that is my minimum expectations! There is a lot of Google information available but I am trying to focus on this example. John Ferrell W8CCW Hi John, I have not built one yet but am contemplating. Mine will use a Rain Bird 1" Auto Sprinkler Valve, electrically actuated (24 VAC or DC). I plan to use a Harbor Freigth 5 in one power source for the air compressor, the pressure gage, and the 24 VAC actuator supply. The power source is $60-$90 depending on the sale going on, it is also handy for lots of other stuff. This will be my first shot because I have this available. As far as the PVC, tire valve, fishing reel, ect. don't have that much experience. As far as line, I have had one break on me after a nice launch with a sling shot. Make sure your line is of good quality. Happy launching. Gary N4AST I bought most of the supplies last night at Home Depot. The Orbit sprinkler valve was only about $12. It is an inline type valve like the one in the artical. I was thinking I would use a long piece of pipe as the accumulator but after doing the math I have decided to go back and get a piece of 3 inch pipe to use. BTW, the cement and primer is available in a single package for about $6.50. I am a little concerned about the loose fit of the projectile in the 1-1/2 inch barrel. I will report back as I continue. John Ferrell W8CCW |
Antenna Launcher
"Howard K0ACF" wrote in message ... The pipe for the barrel is 1 1/4 in. 24 in. long. The end caps for the projectile are 3/4 in. so there is not to much of a loose fit. I haven't made one myself but a friend of mine has & it does just like the article say's, use with caution & safety. I'm interested how it works with a tennis ball, that sounds real neat. Howard K0ACF "John Ferrell" wrote in message I don't have that QST but I built one like this: http://www.qsl.net/k5lxp/projects/La.../Launcher.html I did wrap a couple of layers of electrical tape over the end caps I used. Found some orange electrical tape that I thought would make it easier to see.. Still sort of loose in the pipe. At 35 psi it will shoot them to about 60 feet or more. My first trial shot put it over my triband beam that is about 55 feet up. Did not mean to do that but just wanted to get the feel of how much psi I should use. I have found 45 psi will put it over the tops of the trees here that are over 70 feet tall. |
Antenna Launcher
On Sat, 28 Nov 2009 11:45:12 -0500, John Ferrell
wrote: On Fri, 27 Nov 2009 17:13:50 -0800 (PST), Gary wrote: On Nov 27, 11:27?am, John Ferrell wrote: There is an artical by W4SSY in the March 2009 QST Magazine. I am planning to duplicate it ... ... snip... I bought most of the supplies last night at Home Depot. The Orbit sprinkler valve was only about $12. It is an inline type valve like the one in the artical. I was thinking I would use a long piece of pipe as the accumulator but after doing the math I have decided to go back and get a piece of 3 inch pipe to use. BTW, the cement and primer is available in a single package for about $6.50. I am a little concerned about the loose fit of the projectile in the 1-1/2 inch barrel. I will report back as I continue. John Ferrell W8CCW It is a 1-1/4" X 24" barrel, the projectiles are two 3/4" end caps on about a 4" scrap of 3/4" PVC.... Test fire at 30 PSI dry.. it huffs and honks! Next: 35 PSI and projectile nearly straight up... disappointing! Next: 45 PSI and leaning towards the woods. Still not too impressing. Next: 52 PSI about 75 degrees toward the woods. Whacked the tree smartly at bout 60 feet or so... Next: 55 PSI a little more vertical... overshot the tree with lots of clearance and passed over several others and rattled down in the woods. I saw it come down but still lost it in the leaves. It is time to get the fishing reel in place! The tire pressure gauge I measured with may not be accurate, it is about 25 years old. BTW: The Orbit sprinkler valve has a manual switch function that opens the valve with a quarter twist of the solenoid. It works so well I may not bother to use the electrical switch. With an air compressor in my garage it will be a while before I test it with a hand pump! I believe there are many ways to boost this thing to more power but keeping the 3X12 tank minimizes the air requirements (pumping) and the 24" barrel is adequate to get the job done. Initial testing leads me to believe that this device will serve my needs! John Ferrell W8CCW |
Antenna Launcher
On Sun, 29 Nov 2009 10:17:37 -0500, "Ralph Mowery"
wrote: "Howard K0ACF" wrote in message .. . The pipe for the barrel is 1 1/4 in. 24 in. long. The end caps for the projectile are 3/4 in. so there is not to much of a loose fit. I haven't made one myself but a friend of mine has & it does just like the article say's, use with caution & safety. I'm interested how it works with a tennis ball, that sounds real neat. Howard K0ACF "John Ferrell" wrote in message I don't have that QST but I built one like this: http://www.qsl.net/k5lxp/projects/La.../Launcher.html I did wrap a couple of layers of electrical tape over the end caps I used. Found some orange electrical tape that I thought would make it easier to see.. Still sort of loose in the pipe. At 35 psi it will shoot them to about 60 feet or more. My first trial shot put it over my triband beam that is about 55 feet up. Did not mean to do that but just wanted to get the feel of how much psi I should use. I have found 45 psi will put it over the tops of the trees here that are over 70 feet tall. That is the model that I planned to use if the available Sprinkler valve had that particular configuration. I was concerned about this model because of the barrel and the tank being of equal volume. It is good to have the testimony that it works as well! I be live it would be easier to build and cost a little less as well. I would lean toward the 1-1/4" barrel bore and the 3/4" tubing projectiles because I have yet to see the 1" end caps described locally. I may get to try a paper towel for a "patch" as used in Black powder fire arms tomorrow. I am anxious to get up the 160 meter inverted L. John Ferrell W8CCW |
Antenna Launcher
"John Ferrell" wrote in message news Next: 55 PSI a little more vertical... overshot the tree with lots of clearance and passed over several others and rattled down in the woods. I saw it come down but still lost it in the leaves. It is time to get the fishing reel in place! The tire pressure gauge I measured with may not be accurate, it is about 25 years old. I found 12 volt DC would work my valve just fine. I used one of the emergency battery boster packs to power mine. It is usually beter to shoot from the woods to an open area if you can. I found a open face spinning reel with some low test line on it. I did not think it would be heavy enough to pull the line over the trees, but it was for a very light line that I used to pull a heavy line back over with. If you use hose clamps to hold the reel on with, clamp it to the air chamber side. I found that if I used the barrel side the clamps restricted the bore. You do not need the projectile to be very tight. I just used some electrical tape to make it fit beter. Used orange as I though it might make it easier to find . |
Antenna Launcher
Gary wrote:
On Nov 27, 11:27�am, John Ferrell wrote: There is an artical by W4SSY in the March 2009 QST Magazine. I am planning to duplicate it for use at my QTH. I am interested in any comments, especially from anyone who may have already built one. My available trees may be about 80 feet so that is my minimum expectations! There is a lot of Google information available but I am trying to focus on this example. John Ferrell W8CCW Hi John, I have not built one yet but am contemplating. Mine will use a Rain Bird 1" Auto Sprinkler Valve, electrically actuated (24 VAC or DC). I plan to use a Harbor Freigth 5 in one power source for the air compressor, the pressure gage, and the 24 VAC actuator supply. 3 9V batteries in series makes a fine source to actuate a sprinkler valve. Put a 0.1 uf (or thereabouts, non critical) capacitor across the pushbutton contacts to make it last a bit longer. The power source is $60-$90 depending on the sale going on, it is also handy for lots of other stuff. This will be my first shot because I have this available. As far as the PVC, tire valve, fishing reel, ect. don't have that much experience. As far as line, I have had one break on me after a nice launch with a sling shot. Make sure your line is of good quality. Happy launching. Gary N4AST |
Antenna Launcher
On Mon, 30 Nov 2009 10:31:12 -0800, Jim Lux
wrote: 3 9V batteries in series makes a fine source to actuate a sprinkler valve. Put a 0.1 uf (or thereabouts, non critical) capacitor across the pushbutton contacts to make it last a bit longer. Got a little further today. It takes too many hands to twist the valve, fiddle with the reel and aim the device. I black vinyl taped a micro switch to the valve assembly with ONE 9 volt battery so that I can thumb it to launch. I also moved the open face reel back to the valve end of the barrel and fabricated (more black tape & paperclip) an eye to pass the line through so that line retrieval with the reel is less awkward. Today's final test was conducted in the dark so I was unable to see much. I launched nearly 90 degrees and it was gone for several seconds so I expect it did well. VK2KC emailed me with some advice. He pointed out that it is usually better to launch from the woods to an open space. I expect that will be the case. It seems to me that this device consists of three components: Barrel, Valve and accumulator. It seems that to change to launching tennis balls would be a matter of fitting a 2-1/2" barrel. I doubt that I am going to find that in my area but I will keep my eyes open. Tomorrow is another day! John Ferrell W8CCW |
Antenna Launcher
John Ferrell wrote in
: On Mon, 30 Nov 2009 10:31:12 -0800, Jim Lux wrote: 3 9V batteries in series makes a fine source to actuate a sprinkler valve. Put a 0.1 uf (or thereabouts, non critical) capacitor across the pushbutton contacts to make it last a bit longer. Got a little further today. It takes too many hands to twist the valve, fiddle with the reel and aim the device. I black vinyl taped a micro switch to the valve assembly with ONE 9 volt battery so that I can thumb it to launch. I also moved the open face reel back to the valve end of the barrel and fabricated (more black tape & paperclip) an eye to pass the line through so that line retrieval with the reel is less awkward. Today's final test was conducted in the dark so I was unable to see much. I launched nearly 90 degrees and it was gone for several seconds so I expect it did well. VK2KC emailed me with some advice. He pointed out that it is usually better to launch from the woods to an open space. I expect that will be the case. It seems to me that this device consists of three components: Barrel, Valve and accumulator. It seems that to change to launching tennis balls would be a matter of fitting a 2-1/2" barrel. I doubt that I am going to find that in my area but I will keep my eyes open. Tomorrow is another day! John Ferrell W8CCW Sorry if my post is as silly as it appears it might be, but just in case it isn't... I've seen people walking dogs in a large park I run in a lot. They have these slingshot/stick type affairs to throw tennis balls with for fast strong dogs to get a lot of exercise fetching them while the owner has an easier time of it. I've never tried one, but from what I've seen, even unconscious practise seems to result in some accuracy, and distance certainly isn't lacking. In short, it might be easier, cheaper and faster to practise with one of those than to devise a more complex launcher. It seems to me that accurately placing a thin line over a branch up to 100 ft high might be easier than learning to fly-cast. Another thing I remember, on a smaller scale by far, is a small stick and two rubber bands, one binding the other over the end of the stick. I was about 6, at a strange house competing with another boy to accurately and strongly catapult nasturtium seeds by releasing them against the stick so the band drew them near-parallel to it at speed. It's very effective because it eases aiming and the recoil is just enough to cause the stick end to slew aside to allow accurate clearance at the crucial instant, something that became immediately apparent at the time I 'invented' it. If the thing were scaled up, for example with a carefully prepared inner tube from a cycle tyre, then maybe the thing can launch a weighted tennis ball and light line accurately with one shot. The trial and error would certainly be a lot lower than the dog-ball-slinger. :) |
Antenna Launcher
John Ferrell wrote:
On Mon, 30 Nov 2009 10:31:12 -0800, Jim Lux wrote: 3 9V batteries in series makes a fine source to actuate a sprinkler valve. Put a 0.1 uf (or thereabouts, non critical) capacitor across the pushbutton contacts to make it last a bit longer. Got a little further today. It takes too many hands to twist the valve, fiddle with the reel and aim the device. I black vinyl taped a micro switch to the valve assembly with ONE 9 volt battery so that I can thumb it to launch. I also moved the open face reel back to the valve end of the barrel and fabricated (more black tape & paperclip) an eye to pass the line through so that line retrieval with the reel is less awkward. Today's final test was conducted in the dark so I was unable to see much. I launched nearly 90 degrees and it was gone for several seconds so I expect it did well. I've found that a single 9V will open a valve if there's not much pressure, the coil is cool, etc. Run the pressure up, grab the thing out of the back of the car where it's been cooking in the sun, etc. and a bit more current through the coil is handy. (Oh yeah, and with 3 alkaline 9Vs, they'll last basically forever, because it will still fire when they're almost dead... use the ones you pulled out of your smoke alarms at home) VK2KC emailed me with some advice. He pointed out that it is usually better to launch from the woods to an open space. I expect that will be the case. It seems to me that this device consists of three components: Barrel, Valve and accumulator. It seems that to change to launching tennis balls would be a matter of fitting a 2-1/2" barrel. I doubt that I am going to find that in my area but I will keep my eyes open. Don't neglect the possibility of using a slightly large barrel with a liner (take a bigger diameter piece of plastic pipe, use a circular saw to rip a slot down the length, and then squeeze it down to fit inside the outer tube. Or a sabot/piston made of closed cell foam (e.g. cut a disc of styrofoam that fits snugly.. or I like polyethylene foam.. it's a bit springier) Or, use one of those squishy fairly dense foam rubber balls (you see them as "stress relievers" as a giveaway at trade show booths, for instance) that are available in a variety of sizes and make a snug fit with the ID of whatever barrel you use. Tomorrow is another day! John Ferrell W8CCW |
Antenna Launcher
On Wed, 02 Dec 2009 03:04:48 -0600, Lostgallifreyan
wrote: Sorry if my post is as silly as it appears it might be, but just in case it isn't... I've seen people walking dogs in a large park I run in a lot. They have these slingshot/stick type affairs to throw tennis balls with for fast strong dogs to get a lot of exercise fetching them while the owner has an easier time of it. I've never tried one, but from what I've seen, even unconscious practise seems to result in some accuracy, and distance certainly isn't lacking. In short, it might be easier, cheaper and faster to practise with one of those than to devise a more complex launcher. It seems to me that accurately placing a thin line over a branch up to 100 ft high might be easier than learning to fly-cast. Another thing I remember, on a smaller scale by far, is a small stick and two rubber bands, one binding the other over the end of the stick. I was about 6, at a strange house competing with another boy to accurately and strongly catapult nasturtium seeds by releasing them against the stick so the band drew them near-parallel to it at speed. It's very effective because it eases aiming and the recoil is just enough to cause the stick end to slew aside to allow accurate clearance at the crucial instant, something that became immediately apparent at the time I 'invented' it. If the thing were scaled up, for example with a carefully prepared inner tube from a cycle tyre, then maybe the thing can launch a weighted tennis ball and light line accurately with one shot. The trial and error would certainly be a lot lower than the dog-ball-slinger. :) I am still open to all leads. I did a Google on "dog ball shooter" and found a lot of interesting posts. I don't think any of them are up to carrying a monofilament line over a 100 foot tree but they are still interesting. My Black Lab enjoys chasing a genuine bowling pin when I throw it but we are both getting too old for that game! It has given her very strong neck muscles. The Hyper dog launcher looks to be effective and inexpensive for the intended purpose. I met a fellow at Home Depot that does a lot of surf fishing in the ocean. He is considering a similar device as my launcher to place his bait further from the beach... Rainy day (flood warnings) in North Carolina today... antenna play on computer today. John Ferrell W8CCW |
Antenna Launcher
John Ferrell wrote in
: I am still open to all leads. I did a Google on "dog ball shooter" and found a lot of interesting posts. I don't think any of them are up to carrying a monofilament line over a 100 foot tree but they are still interesting. My Black Lab enjoys chasing a genuine bowling pin when I throw it but we are both getting too old for that game! It has given her very strong neck muscles. The Hyper dog launcher looks to be effective and inexpensive for the intended purpose. I met a fellow at Home Depot that does a lot of surf fishing in the ocean. He is considering a similar device as my launcher to place his bait further from the beach... Rainy day (flood warnings) in North Carolina today... antenna play on computer today. John Ferrell W8CCW One thing I didn't catch was how often you might need to relaunch.. If lots, then for consistency your gadget will win easily. I'd still try the inner- tube elastic and 3 foot stick wheeze though. I also tried making bows and arrows as a kid and was hopeless, but the straight-stick catapult really scored.. (I'm surrounded by 4-floor buildings though so this is sort of rhetorical, I couldn't actually do it on anything but a short trajectory to ground here without breaking something). |
Antenna Launcher
On Sun, 29 Nov 2009 20:11:29 -0500, "Ralph Mowery"
wrote: You do not need the projectile to be very tight. I just used some electrical tape to make it fit beter. Used orange as I though it might make it easier to find . Yech. One of the local hams was trying to use one and had the same fit problem. Somehow, I got involved. The first thing I did was toss a little household flour into the launch tube so I could see if the ball was leaking. Someone appeared up with a camcorder that would do about slow motion. Kinda like that TV show that shows things in slow motion. The tennis ball leaked really badly. Time to fix the leak. I decide to make a new projectile in the shape of a Civil War Minie Ball. http://en.wikipedia.org/wiki/Mini%C3%A9_ball The idea was to have a conical head for improved aerodynamics and an expanding base for a good seal. Of course, friction had to be minimal. To improve the seal, I found some close cell urethane foam. Using a hot nichrome wire, I cut a simple cylinder that was slightly smaller than the bore diameter, and about the length of a beer can. Well, it was the exact size of a beer can because that was what we were launching nearby with a propane powered canon. Anyway, I also used the hot wire to form a somewhat conical cavity in the base. Air pressure would expand the base outward towards the barrel wall, forming a better gas seal. The length of the foam would keep it from wobbling. As long as the foam was a loose fit, there would be little added friction. I never got around to building a conical projectile and just dumped the tennis ball on top of the foam forming a sabot. As I recall, we got about 60 ft with 50 lbs pressure using only the tennis ball, and about 90 ft at 50 lbs using the foam Minie Ball. Videos of the trajectory showed that the air resistance of the tennis ball was only a little better than if it had been dragging a parachute. End of flight droop was severe. A better aerodynamic shape would certainly have been a major improvement. However, I never tried. It would also be fairly easy to add spin stabilization, but that would require a one piece conical projectile. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
Antenna Launcher
John Ferrell wrote:
There is an artical by W4SSY in the March 2009 QST Magazine. I am planning to duplicate it for use at my QTH. I am interested in any comments, especially from anyone who may have already built one. My available trees may be about 80 feet so that is my minimum expectations! There is a lot of Google information available but I am trying to focus on this example. John Ferrell W8CCW I think I have a good one for this thread. Get about 500 feet of 24 to 28 AWG magnet wire and wind it onto a fishing pole that has the easy cast and not an ocean reel. Put on a fair sized weight and then cast over the first tree in sight. Have someone walk around and find the weight on the ground and throw it over the next tree. Do this until the wire is used up or there are no more usable trees. I am going to try it on my next outing. Bill Baka SWL only. |
Antenna Launcher
On Fri, 04 Dec 2009 11:30:53 -0800, Bill Baka
wrote: I think I have a good one for this thread. Get about 500 feet of 24 to 28 AWG magnet wire and wind it onto a fishing pole that has the easy cast and not an ocean reel. Put on a fair sized weight and then cast over the first tree in sight. Have someone walk around and find the weight on the ground and throw it over the next tree. Do this until the wire is used up or there are no more usable trees. I am going to try it on my next outing. Bill Baka SWL only. After today's experience I think I can see a problem coming for you. I was ready to move to the second tree today. After a couple of false starts (valve leaking around pipe threads & add the second battery per advice) I popped the line over the intended tree plus two more. The line ran out smoothly but stopped with a jerk. I ran out of line on the reel! The projectile was hanging about 30 feet from the ground. After much fussing around I managed to reel in enough line get to the top of the intended tree. It seems to be best to reel the line in very slowly because the projectile tends to flip around the limbs and wrap itself tightly. That is what happened to today's effort. The projectile is tightly jammed at about 65 feet up the tree with a good portion of the available line out of reach. I took the XYL to dinner and stopped by WalMart for more line for tomorrow... What I am getting to is that you will need a plan for what to do when you pitch the weight in the tree and it don't come down! 100% chance of precipitation tomorrow afternoon (may be even snow) in the North Carolina Piedmont. Great antenna weather! John Ferrell W8CCW |
Antenna Launcher
On Fri, 04 Dec 2009 20:40:09 -0500, John Ferrell
wrote: What I am getting to is that you will need a plan for what to do when you pitch the weight in the tree and it don't come down! Hi John, Barring snags, time and gravity always wins. 73's Richard Clark, KB7QHC |
Antenna Launcher
"John Ferrell" wrote in message ... On Fri, 04 Dec 2009 11:30:53 -0800, Bill Baka wrote: I think I have a good one for this thread. Get about 500 feet of 24 to 28 AWG magnet wire and wind it onto a fishing pole that has the easy cast and not an ocean reel. Put on a fair sized weight and then cast over the first tree in sight. Have someone walk around and find the weight on the ground and throw it over the next tree. Do this until the wire is used up or there are no more usable trees. I am going to try it on my next outing. Bill Baka SWL only. After today's experience I think I can see a problem coming for you. I was ready to move to the second tree today. After a couple of false starts (valve leaking around pipe threads & add the second battery per advice) I popped the line over the intended tree plus two more. The line ran out smoothly but stopped with a jerk. I ran out of line on the reel! The projectile was hanging about 30 feet from the ground. After much fussing around I managed to reel in enough line get to the top of the intended tree. It seems to be best to reel the line in very slowly because the projectile tends to flip around the limbs and wrap itself tightly. That is what happened to today's effort. The projectile is tightly jammed at about 65 feet up the tree with a good portion of the available line out of reach. I took the XYL to dinner and stopped by WalMart for more line for tomorrow... What I am getting to is that you will need a plan for what to do when you pitch the weight in the tree and it don't come down! 100% chance of precipitation tomorrow afternoon (may be even snow) in the North Carolina Piedmont. Great antenna weather! John Ferrell W8CCW You probably should have just cut the line off the reel and let the weight drop. When I miss, I cut the weight off and reel it back in, then reattach the weight. As mentioned, the weight will tend to wrap around places where it is not wanted. Looks like a radio day for me to John as I am just down the road near Salisbury. DE KU4PT |
Antenna Launcher
Richard Clark wrote in
: On Fri, 04 Dec 2009 20:40:09 -0500, John Ferrell wrote: What I am getting to is that you will need a plan for what to do when you pitch the weight in the tree and it don't come down! Hi John, Barring snags, time and gravity always wins. 73's Richard Clark, KB7QHC No, no, the snags are going to win. :) Friction can be a vicious mistress. Which might mean that very cold wet conditions favour the business, as it happens... One thought... how acccurate is this launcher? Any chance it can be aimed to hit the branch above target and bounce to assist further directed travel? (Sadly I wouldn't trust my stick and elastic trick with that move). |
Antenna Launcher
John Ferrell wrote:
On Fri, 04 Dec 2009 11:30:53 -0800, Bill Baka wrote: I think I have a good one for this thread. Get about 500 feet of 24 to 28 AWG magnet wire and wind it onto a fishing pole that has the easy cast and not an ocean reel. Put on a fair sized weight and then cast over the first tree in sight. Have someone walk around and find the weight on the ground and throw it over the next tree. Do this until the wire is used up or there are no more usable trees. I am going to try it on my next outing. Bill Baka SWL only. After today's experience I think I can see a problem coming for you. I was ready to move to the second tree today. After a couple of false starts (valve leaking around pipe threads & add the second battery per advice) I popped the line over the intended tree plus two more. The line ran out smoothly but stopped with a jerk. I ran out of line on the reel! The projectile was hanging about 30 feet from the ground. After much fussing around I managed to reel in enough line get to the top of the intended tree. It seems to be best to reel the line in very slowly because the projectile tends to flip around the limbs and wrap itself tightly. That is what happened to today's effort. The projectile is tightly jammed at about 65 feet up the tree with a good portion of the available line out of reach. I took the XYL to dinner and stopped by WalMart for more line for tomorrow... What I am getting to is that you will need a plan for what to do when you pitch the weight in the tree and it don't come down! 100% chance of precipitation tomorrow afternoon (may be even snow) in the North Carolina Piedmont. Great antenna weather! John Ferrell W8CCW I have a big reel of magnet wire about 22 or 24 AWG, meaning probably miles of it, so I can lose some. A lead weight is disposable so I won't cry over it. I may leave some of these antennas at favorite spots for future use. A fishing rod just casts really far for me so it is my weapon of choice. Bill Baka |
Antenna Launcher
On Fri, 4 Dec 2009 23:23:39 -0500, "Ralph Mowery"
You probably should have just cut the line off the reel and let the weight drop. When I miss, I cut the weight off and reel it back in, then reattach the weight. As mentioned, the weight will tend to wrap around places where it is not wanted. Looks like a radio day for me to John as I am just down the road near Salisbury. DE KU4PT Good advice! John Ferrell W8CCW |
Antenna Launcher
On Fri, 04 Dec 2009 22:48:38 -0600, Lostgallifreyan
wrote: No, no, the snags are going to win. :) Friction can be a vicious mistress. Which might mean that very cold wet conditions favour the business, as it happens... One thought... how acccurate is this launcher? Any chance it can be aimed to hit the branch above target and bounce to assist further directed travel? (Sadly I wouldn't trust my stick and elastic trick with that move). Too many non-precse variables for accuracy. Air pressure, temperature, elastic accumulator, projectile geometry and line drag. John Ferrell W8CCW John Ferrell W8CCW |
Antenna Launcher
On Nov 27, 12:27*pm, John Ferrell wrote:
There is an artical by W4SSY in the March 2009 QST Magazine. I am planning to duplicate it for use at my QTH. I am interested in any comments, especially from anyone who may have already built one. My available trees may be about 80 feet so that is my minimum expectations! There is a lot of Google information available but I am trying to focus on this example. John Ferrell W8CCW I wonder if my spud gun could be used for this. No compressor required. Jimmie |
Antenna Launcher
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Antenna Launcher
On 6 dic, 15:22, John Ferrell wrote:
On Fri, 04 Dec 2009 22:48:38 -0600, Lostgallifreyan wrote: No, no, the snags are going to win. :) Friction can be a vicious mistress. Which might mean that very cold wet conditions favour the business, as it happens... One thought... how acccurate is this launcher? Any chance it can be aimed to hit the branch above target and bounce to assist further directed travel? (Sadly I wouldn't trust my stick and elastic trick with that move). Too many non-precse variables for accuracy. Air pressure, temperature, elastic accumulator, projectile geometry and line drag. John Ferrell W8CCW John Ferrell W8CCW Hello John, In my opinion pneumatic systems can have good shot to shot performance. When you use projectiles of about 0.1 kg width about 25mm diameter, the required muzzle velocity is in the 25 m/s range (to reach 70 ft). As this is far below speed of sound, mass of the gas, hence temperature effect should be negligible. The weight to diameter ratio assures that air friction has less then 10% influence on height and distance. Maybe you can add something to avoid tumbling of the projectile. When you have a large bore fast opening valve ( 10ms) you should have good performance with relative low pressure (50 psi). When you experience bad repeatability, it must be the valve. If you like to experiment further, you may construct your own piston valve that interfaces directly with the barrel (coaxial structure). Over here (Netherlands), law is very strict. Even pneumatic spud guns are weapons and you may not make them as far as I know. Good luck with the launcher! Wim PA3DJS www.tetech.nl remove abc in case of PM. |
Antenna Launcher
On Dec 4, 11:48*pm, Lostgallifreyan wrote:
Richard Clark wrote : On Fri, 04 Dec 2009 20:40:09 -0500, John Ferrell wrote: What I am getting to is that you will need a plan for what to do when you pitch the weight in the tree and it don't come down! Hi John, Barring snags, time and gravity always wins. * 73's Richard Clark, KB7QHC No, no, the snags are going to win. :) Friction can be a vicious mistress.. Which might mean that very cold wet conditions favour the business, as it happens... One thought... how acccurate is this launcher? Any chance it can be aimed to hit the branch above target and bounce to assist further directed travel? (Sadly I wouldn't trust my stick and elastic trick with that move). Having tried this several different ways, my advice: Just shoot over the tree. Trying to shoot between a set of branches in the tree may sometimes make sense but I've never encountered a situation where it was best. Now, the gotcha is, if you shoot over the tree, you might also clear the 3 or 5 trees behind that! What I do is use a fishing reel and reach out and gently grab the fishing line after the ball clears the first tree. This kills the forward momentum of the ball. Then: LET GO and let the ball and line drop. Cutting a slit in the tennis ball and loading it up with washers or pennies can give it a little extra weight. Yes, I've stranded a few tennis balls in trees over the years. Tim N3QE. |
Antenna Launcher
On Dec 6, 9:42*am, JIMMIE wrote:
On Nov 27, 12:27*pm, John Ferrell wrote: There is an artical by W4SSY in the March 2009 QST Magazine. I am planning to duplicate it for use at my QTH. I am interested in any comments, especially from anyone who may have already built one. My available trees may be about 80 feet so that is my minimum expectations! There is a lot of Google information available but I am trying to focus on this example. John Ferrell W8CCW I wonder if my spud gun could be used for this. No compressor required. Jimmie Yes. My one afternoon with a spud gun was conclusive. That sucker will throw a potato hundreds of feet. My host that day insisted that nobody raise the barrel above about 30 degrees because the spuds would go over the woods and onto his neighbor's property, which we could not even see! Propellant is a one-second spritz of hair spray. Not sure what kind of line to insert through the potato, though. Kite-cord? Monofilament? |
Antenna Launcher
On Dec 11, 11:28*pm, "Sal M. Onella" wrote:
On Dec 6, 9:42*am, JIMMIE wrote: On Nov 27, 12:27*pm, John Ferrell wrote: There is an artical by W4SSY in the March 2009 QST Magazine. I am planning to duplicate it for use at my QTH. I am interested in any comments, especially from anyone who may have already built one. My available trees may be about 80 feet so that is my minimum expectations! There is a lot of Google information available but I am trying to focus on this example. John Ferrell W8CCW I wonder if my spud gun could be used for this. No compressor required. Jimmie Yes. *My one afternoon with a spud gun was conclusive. *That sucker will throw a potato hundreds of feet. *My host that day insisted that nobody raise the barrel above about 30 degrees because the spuds would go over the woods and onto his neighbor's property, which we could not even see! *Propellant is a one-second spritz of hair spray. *Not sure what kind of line to insert through the potato, though. *Kite-cord? Monofilament?- Hide quoted text - - Show quoted text - Just clamp the old Zebco on the side. Jimmie |
Antenna Launcher
On Dec 11, 11:41*pm, JIMMIE wrote:
On Dec 11, 11:28*pm, "Sal M. Onella" wrote: On Dec 6, 9:42*am, JIMMIE wrote: On Nov 27, 12:27*pm, John Ferrell wrote: There is an artical by W4SSY in the March 2009 QST Magazine. I am planning to duplicate it for use at my QTH. I am interested in any comments, especially from anyone who may have already built one. My available trees may be about 80 feet so that is my minimum expectations! There is a lot of Google information available but I am trying to focus on this example. John Ferrell W8CCW I wonder if my spud gun could be used for this. No compressor required. Jimmie Yes. *My one afternoon with a spud gun was conclusive. *That sucker will throw a potato hundreds of feet. *My host that day insisted that nobody raise the barrel above about 30 degrees because the spuds would go over the woods and onto his neighbor's property, which we could not even see! *Propellant is a one-second spritz of hair spray. *Not sure what kind of line to insert through the potato, though. *Kite-cord? Monofilament?- Hide quoted text - - Show quoted text - Just clamp the old Zebco on the side. Jimmie- Hide quoted text - - Show quoted text - Handle and battery pack from a cordless drill, spark coil off a lawnmower engine. Potato bazooka for your bazooka antenna. Jimmie |
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