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Post by formulamojo on Jan 25, 2007 17:48:38 GMT -5
What is the general opinion on the astroplane omni directional antenna? I have acquired one to use with my base set up and the guy I got it from uses one and talks with no problems all over the country and canada.
I need to know some details like how to mount it, should it be grounded or ungrounded, stuff like that.
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Post by Tramfan on Jan 25, 2007 22:34:07 GMT -5
I had one several years ago. I had no complaints with it. I had mine mounted on 20' or so of regular mast and talked all over on it. A pretty stout antenna that will stand up well to wind and ice, and a lightning hit won't destroy it like the fiberglass throw-aways they sell these days.
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Lonestar
Big Bucket Mouth
Texicanus Irrepressiblus
Posts: 97
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Post by Lonestar on Feb 1, 2007 2:01:07 GMT -5
The antenna should be grounded, for lightning protection and to prevent static charges from getting into the front end of the radio.
Make sure that the mounting clamp makes solid contact with the mast, and that mast sections are electrically connected [thread self-tapping screws into where they overlap]. Connect the bottom of the mast to a 4-to-8-foot copper ground rod with solid wire. Alternatively, run a solid ground wire from the antenna mounting to the ground rod.
I've thought of building an Astroplane from scratch. ;D It's supposed to have 4.46 dB gain and a relatively flat [more toward the horizon than upward] radiation pattern.
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Post by 2IR473 on Feb 1, 2007 9:57:36 GMT -5
from what I've read, the Astroplane is basically a 1/4 wave antenna, so it should display the characteristics of all 1/4 wave antennas. Not really a lot of gain, but a good antenna that may work better for you if you are limited in mounting height. It should perform similarly to an Antron 99.
Grounding the antenna will help discharge static build up that occurs in different atmospheric conditions. This will make your receive quieter and help you hear weaker stations.
I ran a 1/4 wave GP antenna for many years and it worked fine. At the time, the band was open and it was simple to work the world. I did get an increase in local coverage when I switched to an Imax 2000 ( .64 wavelength), but that is just the physics of antennas. A 5/8 or .64 ~ antenna will offer more gain than a 1/4~ antenna, but you will do fine with that antenna.
Get some decent coax cable to feed the antenna. That will really help you. RG-8, RG-213...something like that will be worth it.
Put it up, get on the air and have some fun.
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**GRUMPY**
Administrator/The Boss
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Post by **GRUMPY** on Feb 1, 2007 13:26:20 GMT -5
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Sandbagger
Administrator/The Boss
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Post by Sandbagger on Feb 2, 2007 7:45:34 GMT -5
The Gain spec for an Astro Plane is 4.46 dbi. A typical 5/8 wave GP has a gain rating of at least 4 dbi. So on a sprec y spec comparison, the Astro Plane would seem to fall right in there. But real world experience paints a somewhat different picture. I owned an Astro Plane back in 1975. I bought it to upgrade my current Radio Shack 1/2 wave, and was impressed by the almost 1 dbi more gain that this antenna advertized over the 1/2 wave. But when I put it up, using the very same mast and coax cable, I found that it performed the same or slightly worse than the 1/2 wave did. Not liking the performance, I then went out and bought a Hustler Trumpet 5/8 wave GP. The difference in performance between the Astro Plane and the 5/8 GP was significant. I had a local who was my "standard" for comparing my signal. He would turn his RF gain all the way down and observe my signal. On the 1/2 wave, I was about an S1 3/4. The Astro Plane was about S1 1/2. The 5/8 wave was S3 (My later Sigma 4 was an S4). I had similar results from other locals as well. In all fairness though, the Astro Plane (and all the other antennas) were mounted to the same 20' length mast. 1/2 and 5/8th wave GP style antennas extend 100% above the mast, while probably 2/3rds of the Astro Plane hangs below the mast. So it was at a bit of a height disadvantage. Also, I lived in a bit of a hole. Practically every direction from my home was uphill. The Astro Plane is also known to have a flatter E-Plane radiation pattern than a typical ground plane, and while that may be desirable for a high mounted clear altitude, it's probably not desirable for those of us who's signal needed to climb out of the hole. As always YMMV, but my observations are based on real world performance under the conditions that I had to live with. People in other situations may see different results.
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**GRUMPY**
Administrator/The Boss
Classic Radio Operator Olde Timer 8220 [/color][/center]
"The King of Ping"
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Post by **GRUMPY** on Feb 2, 2007 8:22:56 GMT -5
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Post by 2IR473 on Feb 2, 2007 9:32:05 GMT -5
I see from the link that Grumpy provided to the manual that they do refer to it as a 5/8 antenna. They say that it has the electrical length of a 5/8 wave antenna, through it's co-inductive design, but it's physical length is closer to a 1/4 wavelength.
So what is it really? Is it a 5/8 wave antenna? a 1/4 wave antenna? some form of mutant strain antenna? ;D
I would be curious to know the difference, since I am not an antenna expert by any stretch of the imagination. I assume the more metal (or fiberglass covered metal) you have in the air, the better that will be.
Does the antenna use the mast as part of the antenna? Does it have a higher or lower angle of radiation from other antennas? Does the capacitance hat lower the take off angle?
Anyone know for sure?
Seems the more I read about the antenna, the more conflicting info I get.
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Post by LuckyStrike on Feb 2, 2007 10:36:10 GMT -5
hello guys. i finally got the net going again after the ice storm. i lost two antennas and dad lost his pdl2's. anyway back to the subject. i have used a astroplane for a few months a while back. it did ok. it heard as well as my penatrator 500, but didnt get out as far. but it was about 10foot lower in the air. if i needed a small antenna i would get another one. i dont think they can handle much power, i dont remember what the spec. is on max power.
Lucky Strike ot740 k0twp
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Sandbagger
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Post by Sandbagger on Feb 2, 2007 14:15:35 GMT -5
Interesting reading, although not being a theoretical "antenna guru", some of the more technical parts of the explanation were a little tough to follow. But it does corroborate my real world findings over 30 years ago, where it was concluded that the AP needed to be mounted high up to be the most effective. At the height I was forced to keep mine at, it was noticably outdone by a standard 5/8ths wave ground plane and edged out sligtly by a 1/2 wave GP. The plus points for the AP were that the SWR didn't change when it rained (A common problem for inductor coil matched 5/8th wave antennas), and it could handle quite a lot of power (Back in '75 500 watts was a LOT of power). Whether an Astro Plane is a good choice for anyone depends on where they live. If you live in a high HAAT elevation, the AP will perform well. The low angle of radiation will reach out far. But if you're at the bottom of a valley, that low radation angle will have your signal beaming right into the side of the neighboring hills rather than trying to climb over them.
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Post by Tramfan on Feb 3, 2007 11:56:14 GMT -5
The Astroplane is a non loading coil type antenna just like my old Starduster, so power-handling shouldn't really be an issue. If an antenna has a loading coil, it allows the antenna to be electrically longer, while being physically shorter. However, if the coil is not made from a very heavy gauge wire, it can limit how much power you can feed into the antenna. Obviously, the heavier the wire gauge, the more power an antenna can handle. Since the Astroplane does not have a loading coil, it really isn't an issue.
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air1
Ratchet Jaw
Posts: 69
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Post by air1 on Feb 6, 2007 11:00:49 GMT -5
Hi! I run an AP from the seventies that I had given to me. I took it apart, cleaned it up, installed new hardware and put it up about four years ago. It's 34' to the top, grounded very good and it gets out great. I live on top of a high hill with clear views for miles in every direction here in southern NY. The antenna has easily withstood 60 mph winds. It's the only one I've owned except for the stainless steel whip mounted on my metal roofed barn that has withstood the wind up here. I think that other 5/8 waves I've had were probably better but this is the only one that stays in the air.
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Post by formulamojo on Feb 6, 2007 22:29:22 GMT -5
Whether an Astro Plane is a good choice for anyone depends on where they live. If you live in a high HAAT elevation, the AP will perform well. The low angle of radiation will reach out far. But if you're at the bottom of a valley, that low radiation angle will have your signal beaming right into the side of the neighboring hills rather than trying to climb over them. I live in the north western part of the lower peninsula of Michigan, the pinky if you will. Kalkaska County is on a plateau above all the surrounding counties. So the astroplane will get out very well, my one problem may be that I live in th middle of mostly state land so some of these trees are friggin huge. I have the astroplane manual and it says anything higher than 36 feet is perfect, but will a nearby tree of 80-100 feet pose a problem? The nearest trees are about 50 feet from the antenna.
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Sandbagger
Administrator/The Boss
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Post by Sandbagger on Feb 7, 2007 7:31:02 GMT -5
Whether an Astro Plane is a good choice for anyone depends on where they live. If you live in a high HAAT elevation, the AP will perform well. The low angle of radiation will reach out far. But if you're at the bottom of a valley, that low radiation angle will have your signal beaming right into the side of the neighboring hills rather than trying to climb over them. I live in the north western part of the lower peninsula of Michigan, the pinky if you will. Kalkaska County is on a plateau above all the surrounding counties. So the astroplane will get out very well, my one problem may be that I live in th middle of mostly state land so some of these trees are friggin huge. I have the astroplane manual and it says anything higher than 36 feet is perfect, but will a nearby tree of 80-100 feet pose a problem? The nearest trees are about 50 feet from the antenna. Well, trees do block signals (Ask anyone with Direct TV who has trees), and the denser the trees are, the more signal attenuation. The higher you go in frequency the worse this becomes, but it does affect CB band signals to some degree. If you live near a dense forest, you have to think of the trees almost like an extension of the ground. For best performance, you should try to get above them. Naturally, the further from your antenna the trees are, the better your chances are. You'll also most likely do better in the winter time when the leaves are off the trees.
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Post by mark4 on Apr 20, 2008 14:09:05 GMT -5
Astro Plane is one of the biggest piece of junk antenna's I have owned. They may say it's a 5/8. That is a joke on the consumer! Also bad for TVI
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Post by BionicChicken on Apr 20, 2008 20:22:36 GMT -5
To say the Astroplane is a piece of junk is totally out of line. Evidently you have limited knowledge of the antennas. A few of the folks out here who have been on the radio for 30+ years have had the chance to use the original Avanti Astroplane and not the "POS" ripoff being sold now should agree with me. The new one compares with the new Starduster which is in the same category. Both are cheap imitations of the real thing. The phrase "Sometimes imitated, never duplicated", comes to mind. I swapped an Antron 99 on a 40' push up pole with an old Avanti Astroplane and the difference was "daylight and dark". The fishing pole was not in the same league as the Astroplane. Noise factor, receive, and transmit were all improved with the Astroplane as well as standing wave 40+ and 40- the regular channels. The Astroplane was swapped out for a Maco V58 which had almost the same improvements over the Astroplane as it did over the A99. The OLD Starduster and Astroplane antennas were some of the best made "in the day" and still perform well today. It's a shame that someone can come along and try to make a buck off of someones else's name and quality just by spending bucks for the copyright. I know others might have had different results and I can respect that........I am just relating my personal experience regarding the antennas. Of course I could open up another can of worms by saying the PDL II is one of the best rotating ground planes ever made...............but I better leave that to another thread.
BC
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Post by mark4 on Apr 20, 2008 22:00:07 GMT -5
Everyone is entitled to their opinion. So don't insult me with mine. I stick by it 100%! For one it is not electrically a 5/8 wave antenna. And not a very good design at that. The only difference with the knock off. Is that it falls apart. Electrically they are the same. And yes, thank you I speak from 30 plus years as a tech and former owner of one.
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Post by doctor on Apr 20, 2008 22:42:40 GMT -5
I have one, it is at 23 feet, with no problems, and is a flat swr of 1 to 1, it has been up for 3 years. Only disadvantage with my astro plane was it was a cheaply material wise built, and where the support goes to the ring broke, so I just sawed a small aluminum tube crossed over to the support coming down from the middle and hose clamped it on a few years ago, and it still works. I would not buy another one from the pipe company but by ce engineering I think it is called, much heavier material. I run it on 11 and 10 meters and get around the country on it on ssb and am with good reports and this isnt with excessive power at all.
DOCTOR/795
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Sandbagger
Administrator/The Boss
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Post by Sandbagger on Apr 21, 2008 7:54:11 GMT -5
Everyone is entitled to their opinion. So don't insult me with mine. I stick by it 100%! For one it is not electrically a 5/8 wave antenna. And not a very good design at that. The only difference with the knock off. Is that it falls apart. Electrically they are the same. And yes, thank you I speak from 30 plus years as a tech and former owner of one. I think we all have opinions about the things that we use. Sometimes we get something we really feel works great. Other times we might have a less-than-ideal experience with a certain product. But I find that many people who praise something do so without the benefit of doing an "A/B" comparison against one or more other products to get a relative comparison. CB antennas is one such area. I've known people to give thumbs up endorsements for a particular antenna, based on the fact that they installed it and they can talk to a bunch of people fairly well with it. Well...... ok but...... Those of us who have been around a while tend to make more objective comparisons. I've owned 4 different omni antennas back in the 70's, including an Astro Plane, and mounted them all to the same mast, and the Astro Plane was pretty much the weakest in signal out of all of them. BUT, and this is the big but, I was probably not being fair to the AP because instead of mounting on top of the mast, the AP sits more than half of it under the top of the mast, which results in lost height. Some other locals have used the Astro Plane with mixed results. Those who mounted it at least 36' above the ground and lived on a relatively high spot, tended to do well with them. Those, (like me) who lived in a relative hole, tended to do poorly with them. The same thing seemed to hold true for the A/S Starduster. I also live in an area with many hills and valleys Now YMMV, and people who live in flatter areas like the midwest, south central, and the sandpile, may see different results. But we should try to at least agree to disagree respectfully.
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Post by mark4 on Jul 26, 2008 10:54:39 GMT -5
Sanbagger I agree with you. This antenna is not a 5/8 wave. A A little over a 1/4 wave. As for being fair to it. I think your comparison is. They promoted this thing as radiating from the top. So you were gaining 15ft. Mounting it at the same height would be a fair comparison. For the manf. to try to pass this thing off as a true 5/8 wave is a joke. I run a V5000 and it is a good antenna. But it is short of being a true 5/8 wave antenna at 27MHZ. Some of the outlandish claims manf. have made over the years just get rehashed as gospel.
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Post by spitfire441 on Jul 26, 2008 17:41:39 GMT -5
Of course I could open up another can of worms by saying the PDL II is one of the best rotating ground planes ever made...............but I better leave that to another thread. BC I am assuming you say that in jest? I love my PDL-2 two element quad beam. Not a goundplane at all, it is a full wave loop or more technically correct is two dipoles feed in phase with a full wave reflecter.
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Sandbagger
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Post by Sandbagger on Jul 26, 2008 19:15:31 GMT -5
Of course I could open up another can of worms by saying the PDL II is one of the best rotating ground planes ever made...............but I better leave that to another thread. BC I am assuming you say that in jest? I love my PDL-2 two element quad beam. Not a goundplane at all, it is a full wave loop or more technically correct is two dipoles feed in phase with a full wave reflecter. I think the comment referred to his belief that the PDL does not have the best front/back rejection ratio. I've always preferred straight yagi beams myself. But a properly built PDL should be fairly good on back rejection. The thing is, I've seen people put them together and not heed the warning in the instructions to measure and string the wire to within a 1/8th inch tolerance. If this is not done as instructed, the rejection of the beam will suffer. Also, the wire will stretch over time and it should be remeasured and restrung if the wire starts to sag.
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Post by spitfire441 on Jul 26, 2008 19:28:22 GMT -5
I am assuming you say that in jest? I love my PDL-2 two element quad beam. Not a goundplane at all, it is a full wave loop or more technically correct is two dipoles feed in phase with a full wave reflecter. I think the comment referred to his belief that the PDL does not have the best front/back rejection ratio. I've always preferred straight yagi beams myself. But a properly built PDL should be fairly good on back rejection. The thing is, I've seen people put them together and not heed the warning in the instructions to measure and string the wire to within a 1/8th inch tolerance. If this is not done as instructed, the rejection of the beam will suffer. Also, the wire will stretch over time and it should be remeasured and restrung if the wire starts to sag. I will concied the point of not the greatest rejection from the rear, however it has a pretty good null on the rear "corners" of the pattern. For convienence, size and ability to switch polarity on the fly as well as forward gain comprable to a 3 element yagi, tuff customer to beat. ;D
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Post by BionicChicken on Jul 26, 2008 21:16:45 GMT -5
Hmmmm. Took a while before the worms got out of the can but I knew one day they would find the way. The wire is very critical on them. If it is not right, nothing will work right. I friend of mine had stacked PDL's with the factory stacking kit at 100'. I spotted him 80 miles and 300 watts and took him out completely with a 5 element. When he turned the antenna from front to back.....front would show a S6 and back a S4 at 80 miles. Not too good rejection. The flat side works pretty good from what I have seen. Not knocking anyones antenna so don't take it that way. Just personal experience..............yours may and probably does differ.
BC
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Sandbagger
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Post by Sandbagger on Jul 26, 2008 21:35:29 GMT -5
Hmmmm. Took a while before the worms got out of the can but I knew one day they would find the way. The wire is very critical on them. If it is not right, nothing will work right. I friend of mine had stacked PDL's with the factory stacking kit at 100'. I spotted him 80 miles and 300 watts and took him out completely with a 5 element. When he turned the antenna from front to back.....front would show a S6 and back a S4 at 80 miles. Not too good rejection. The flat side works pretty good from what I have seen. Not knocking anyones antenna so don't take it that way. Just personal experience..............yours may and probably does differ. BC Yea, everone has different experiences, and we all have similar signal comparison stories. One of my favorites was how one guy with a barefoot CAM 88 and a ground plane could outdo another guy with 300 watts and a PDL beam in ground wave distance signal. One might be tempted to conclude that the PDL was not doing the job. But the real reason was that the guy with the barefoot radio was at about 800' of elevation while the guy with the 300 watts and the PDL was at less than 250' ASL. When comparing signal between antennas, running different antennas at different stations could be affected by variables such as terrain and elevation, as well as subtle differences in mounting and transmitter power. So the only fair way is to minimize the variables by doing a side-side comparison at the same location in the same mounting position with the same transmitting equipment. Spitfire's PDL gives me slightly less signal than his Alpha 5/8th ground plane. But the ground plane has a 20' height advantage. So what's all that worth?
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Post by spitfire441 on Jul 27, 2008 5:37:34 GMT -5
Hmmmm. Took a while before the worms got out of the can but I knew one day they would find the way. The wire is very critical on them. If it is not right, nothing will work right. I friend of mine had stacked PDL's with the factory stacking kit at 100'. I spotted him 80 miles and 300 watts and took him out completely with a 5 element. When he turned the antenna from front to back.....front would show a S6 and back a S4 at 80 miles. Not too good rejection. The flat side works pretty good from what I have seen. Not knocking anyones antenna so don't take it that way. Just personal experience..............yours may and probably does differ. BC Yea, everone has different experiences, and we all have similar signal comparison stories. One of my favorites was how one guy with a barefoot CAM 88 and a ground plane could outdo another guy with 300 watts and a PDL beam in ground wave distance signal. One might be tempted to conclude that the PDL was not doing the job. But the real reason was that the guy with the barefoot radio was at about 800' of elevation while the guy with the 300 watts and the PDL was at less than 250' ASL. When comparing signal between antennas, running different antennas at different stations could be affected by variables such as terrain and elevation, as well as subtle differences in mounting and transmitter power. So the only fair way is to minimize the variables by doing a side-side comparison at the same location in the same mounting position with the same transmitting equipment. Spitfire's PDL gives me slightly less signal than his Alpha 5/8th ground plane. But the ground plane has a 20' height advantage. So what's all that worth? I would say, that either antenna is worth more than the value in scrap aluminum, however that may change soon. I really need to get the PDL up as high or higher than the GP. A good test would be the PDL at the same hight, then do my two 5/8 co-phase then see who wins. (of my own antennas)
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Post by spitfire441 on Jul 27, 2008 6:02:35 GMT -5
Hmmmm. Took a while before the worms got out of the can but I knew one day they would find the way. The wire is very critical on them. If it is not right, nothing will work right. I friend of mine had stacked PDL's with the factory stacking kit at 100'. I spotted him 80 miles and 300 watts and took him out completely with a 5 element. When he turned the antenna from front to back.....front would show a S6 and back a S4 at 80 miles. Not too good rejection. The flat side works pretty good from what I have seen. Not knocking anyones antenna so don't take it that way. Just personal experience..............yours may and probably does differ. BC One additional thought to the rejection issue. Yes I agree the PDL is not the greatest in rear rejection. However on that thought if the test was at 180 degrees from the front that does not surprise me. What would the signal be like at 120 or 240 degrees? That is where most beams, yagis or quads, have the deepest null. If you plot any beam on a Smith chart you will see that (most) all beams have a small lobe at the rear or 180 degrees from front. The deepest nulls will be at the rear "corners", 120 and 240 degrees. I have played with many beams for many different frequency bands and that always seems to be the case. On that note, the best front to back ratio on any antenna system I have had was my stacked 33 element 903 mhz beams (26 dbd forwrd gain!). It was as sharp as a laser in the front, and you were gone in the rear.
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Post by mark4 on Jul 27, 2008 10:00:48 GMT -5
I had 2 friends with a PDLII. Not impressed by this antenna. But that is just 2 people that I know of.
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Post by zman on Sept 23, 2008 22:40:07 GMT -5
I have an Astroplane i use as a standby. I have never really talked off of it but it does have good ears. I live were it is flat so the flat pattern it has on TX would work well around here. The antenna was designed for those that didn't want to install an antenna very high, but wanted decent performance for local contacts.
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Post by doctor on Sept 24, 2008 8:54:45 GMT -5
Where did you get the astroplane, I had one from the pipe company, the material is so cheap it must be handled with kid gloves or it falls apart.
DOCTOR/795
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