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Need help... End-fed, long wire or ????
Hey, here's a question for you antenna heads..... I've googled and not found
much but a million opinions and ideas on which is better so I thought I'd come here and lay out the situation and get some advice. I want to put an HF radio back in the house. I only have a small yard and pesky neighbors. I want to operate ham and MARS freqs. I need to be somewhat incognito. A tower is out, and a big vertical is questionable. I don't like the radial issue as I live on solid rock, nor the price issues. My only option is to go out back... zero yard but a hillside that is almost limitless, however; I live on top of a ridge so the hills all go downward. I'm assuming a long wire in the treetops or similar is my only hope. [very few trees are higher than my house up here, LOL] SO... if you only had one direction to throw an antenna out, but could arrow a 300 footer through the treetops if need be, what would you do? Which style antenna would be best? Random or folded or ? I'm assuming end-fed is my only option here, with only one direction to go. [Southerly] I'm considering a manual tuner in the shack, or auto-tuner like a marine unit that I could remote in the attic and coax up to it then wire to outside. Is there a better way?? Ideas? Input? thanks for the help! Woody |
Need help... End-fed, long wire or ????
On Mon, 09 Jul 2007 02:14:51 GMT, "Woody" wrote:
SO... if you only had one direction to throw an antenna out, but could arrow a 300 footer through the treetops if need be, what would you do? Hi Woody, Go for it! It's not like an act of desperation or anything like that. I had a similar situation (although more options) with an ad-hoc hillside longwire (same size, height, etc.). It worked like gang-busters. Which style antenna would be best? Random or folded or ? Just as you described it. Anything more convoluted is unlikely to give you more performance. 73's Richard Clark, KB7QHC |
Need help... End-fed, long wire or ????
Thread a longwire through the trees... Have a quarter wave radial on
the ground for each band you intend to operate - this is the RF counterpoise for the antenna tuner so it doesn't bite your fingers... Operate and enjoy.. On a ridge as you describe, it should work just fine... denny |
Need help... End-fed, long wire or ????
On Mon, 09 Jul 2007 02:14:51 GMT, "Woody" wrote:
Hey, here's a question for you antenna heads..... I've googled and not found much but a million opinions and ideas on which is better so I thought I'd come here and lay out the situation and get some advice. I want to put an HF radio back in the house. I only have a small yard and pesky neighbors. I want to operate ham and MARS freqs. I need to be somewhat incognito. A tower is out, and a big vertical is questionable. I don't like the radial issue as I live on solid rock, nor the price issues. My only option is to go out back... zero yard but a hillside that is almost limitless, however; I live on top of a ridge so the hills all go downward. I'm assuming a long wire in the treetops or similar is my only hope. [very few trees are higher than my house up here, LOL] SO... if you only had one direction to throw an antenna out, but could arrow a 300 footer through the treetops if need be, what would you do? Which style antenna would be best? Random or folded or ? I'm assuming end-fed is my only option here, with only one direction to go. [Southerly] I'm considering a manual tuner in the shack, or auto-tuner like a marine unit that I could remote in the attic and coax up to it then wire to outside. Is there a better way?? Ideas? Input? thanks for the help! Woody I am happy with my SGC-237 tuner. It has a wide range of matching capability and keeps the RF at the antenna instead of the shack. John Ferrell W8CCW "Life is easier if you learn to plow around the stumps" |
Need help... End-fed, long wire or ????
Ok, maybe that's what I'll do then... So should I use a balun of any kind or
just make a coax connection of my own? Woody "Richard Clark" wrote in message ... On Mon, 09 Jul 2007 02:14:51 GMT, "Woody" wrote: SO... if you only had one direction to throw an antenna out, but could arrow a 300 footer through the treetops if need be, what would you do? Hi Woody, Go for it! It's not like an act of desperation or anything like that. I had a similar situation (although more options) with an ad-hoc hillside longwire (same size, height, etc.). It worked like gang-busters. Which style antenna would be best? Random or folded or ? Just as you described it. Anything more convoluted is unlikely to give you more performance. 73's Richard Clark, KB7QHC |
Need help... End-fed, long wire or ????
OK.... so work with the ignorant here.. I've never used anything other than
my trusty dipole/folded dipoles... How do I put in radials under a longwire?? I'm kind of on a cliff so not sure where I could do any digging back there... A good website for the longwire user would be fantastic and I could just research it. thanks! Woody "Denny" wrote in message ups.com... Thread a longwire through the trees... Have a quarter wave radial on the ground for each band you intend to operate - this is the RF counterpoise for the antenna tuner so it doesn't bite your fingers... Operate and enjoy.. On a ridge as you describe, it should work just fine... denny |
Need help... End-fed, long wire or ????
Ya know ... if I had my druthers... and I don't.. lol...
I'd go for a Motorola Micom 500e setup or a Harris, or an SGC radio... Not sure I can afford any of them though! Collecting my pennies though. Woody "John Ferrell" wrote in message ... On Mon, 09 Jul 2007 02:14:51 GMT, "Woody" wrote: Hey, here's a question for you antenna heads..... I've googled and not found much but a million opinions and ideas on which is better so I thought I'd come here and lay out the situation and get some advice. I want to put an HF radio back in the house. I only have a small yard and pesky neighbors. I want to operate ham and MARS freqs. I need to be somewhat incognito. A tower is out, and a big vertical is questionable. I don't like the radial issue as I live on solid rock, nor the price issues. My only option is to go out back... zero yard but a hillside that is almost limitless, however; I live on top of a ridge so the hills all go downward. I'm assuming a long wire in the treetops or similar is my only hope. [very few trees are higher than my house up here, LOL] SO... if you only had one direction to throw an antenna out, but could arrow a 300 footer through the treetops if need be, what would you do? Which style antenna would be best? Random or folded or ? I'm assuming end-fed is my only option here, with only one direction to go. [Southerly] I'm considering a manual tuner in the shack, or auto-tuner like a marine unit that I could remote in the attic and coax up to it then wire to outside. Is there a better way?? Ideas? Input? thanks for the help! Woody I am happy with my SGC-237 tuner. It has a wide range of matching capability and keeps the RF at the antenna instead of the shack. John Ferrell W8CCW "Life is easier if you learn to plow around the stumps" |
Need help... End-fed, long wire or ????
On Mon, 09 Jul 2007 22:46:51 GMT, "Woody" wrote:
Ok, maybe that's what I'll do then... So should I use a balun of any kind or just make a coax connection of my own? Hi Woody, To answer this and your other question about radials, I will use my own experience. I drove a ground rod at a remote point, about 12 feet from the house and closer to the woods. My shack was at ground level and this rod was more an anchor for a former vertical (where the rod extended up out of the ground for a foot). Anyway, my principle ground was the service ground 6 feet from my operating position with both rods tied together. At the remote rod (basically at the crest of the ridge), I fanned out radials down the slope. Don't worry about tuning them, or cutting them for a band, the proximity of ground completely negates any sense of tune. At this remote point, I built a box that contained a choke (a short length of coax with 50 or 70 beads) that terminated in a BNC bulkhead connector at one end, and two porcelain posts. One post was tied to the radial field, the other post was tied to the skywire. This put the system ground out at the feedpoint when I ran battery (I always do unless I am on a float charge). This means any house noise was 12 feet further away than would have normally been encountered and snubbed properly by the choke. I measured this and found it to be quite effective for noise control alone. The sky wire (12 ga THNN) merely lifted off from about 1 foot off the ground up to the canopy (Maples) around 60 feet above. The wire ran down the hill, on top of the canopy for about 200 feet. At the remote end, I simply tied it to a limb (at ground level, the wire ending somewhere high above) through a length of 1/16th inch nylon line (crab-pot line). So, from the feedpoint to on-high, the wire basically described a sideways V with ground (as the slope also fell beneath it too at roughly the same angle of 25 degrees). During a storm, two of my Maples snapped about 30 feet above ground level (but down the slope) and one lay over horizontal, and was suspended there 20 feet above ground by snagging other trees. The traditional term for that 30 foot length of tree in this area is called a "widow maker." On its way down, it hit my wire, ripped the box off the post, yanked the coax along until it strained my house connection and broke the coax connection there. After the storm, I hove the wire over the widow maker, confirmed the 1/16th inch nylon withstood the strain (who wulda thought?) and repaired the stripped BNC house connection. Amazingly only the ground wire to the radial field broke when the box started to fly. We get messages here from those who agonize about setting the woods on fire - never happened to me, and I never worried about it. 73's Richard Clark, KB7QHC |
Need help... End-fed, long wire or ????
Woody,
you have received plenty of advice... Let me simplify if I may.. The tuner has to sit within reach usually, so that means the end of the long wire drops down into the shack to the tuner, no coax involved... No baluns, etc. are needed or advised... On certain bands the case of the antenna tuner is likely to bite you when you touch it and the rig also The cure for this is to run a quarter wave radial for each band from the ground terminal of the tuner... These can be run around in the room, or exit out the window and fan out on the ground can be slit into the dirt, whatever MFJ actually makes a tuner for the ground radials.. Works quite well... The purpose of the ground radial is to act as a counterpoise for the antenna currents reduces ground current losses and to move the RF peak voltage out to the end of the quarter wave radial leaving the tuner/radio at low RF potential... Don't over analyze this... Just hang your longwire, put out your ground radials, and have fun on the bands... denny / k8do |
Need help... End-fed, long wire or ????
On Tue, 10 Jul 2007 04:19:44 -0700, Denny wrote:
Woody, you have received plenty of advice... Let me simplify if I may.. The tuner has to sit within reach usually, so that means the end of the long wire drops down into the shack to the tuner, no coax involved... No baluns, etc. are needed or advised... On certain bands the case of the antenna tuner is likely to bite you when you touch it and the rig also The cure for this is to run a quarter wave radial for each band from the ground terminal of the tuner... The SGC-237 keeps the bite outside with the antenna. No RF in the shack! It does need a source of 12 Volts to power it. There may be less expensive auto tuners but I am really tired of having to buy cheaper models only to eventually buy the top of the line... John Ferrell W8CCW "Life is easier if you learn to plow around the stumps" |
Need help... End-fed, long wire or ????
Great, thanks! Really appreciate it,
Woody "Richard Clark" wrote in message ... On Mon, 09 Jul 2007 22:46:51 GMT, "Woody" wrote: Ok, maybe that's what I'll do then... So should I use a balun of any kind or just make a coax connection of my own? Hi Woody, To answer this and your other question about radials, I will use my own experience. I drove a ground rod at a remote point, about 12 feet from the house and closer to the woods. My shack was at ground level and this rod was more an anchor for a former vertical (where the rod extended up out of the ground for a foot). Anyway, my principle ground was the service ground 6 feet from my operating position with both rods tied together. At the remote rod (basically at the crest of the ridge), I fanned out radials down the slope. Don't worry about tuning them, or cutting them for a band, the proximity of ground completely negates any sense of tune. At this remote point, I built a box that contained a choke (a short length of coax with 50 or 70 beads) that terminated in a BNC bulkhead connector at one end, and two porcelain posts. One post was tied to the radial field, the other post was tied to the skywire. This put the system ground out at the feedpoint when I ran battery (I always do unless I am on a float charge). This means any house noise was 12 feet further away than would have normally been encountered and snubbed properly by the choke. I measured this and found it to be quite effective for noise control alone. The sky wire (12 ga THNN) merely lifted off from about 1 foot off the ground up to the canopy (Maples) around 60 feet above. The wire ran down the hill, on top of the canopy for about 200 feet. At the remote end, I simply tied it to a limb (at ground level, the wire ending somewhere high above) through a length of 1/16th inch nylon line (crab-pot line). So, from the feedpoint to on-high, the wire basically described a sideways V with ground (as the slope also fell beneath it too at roughly the same angle of 25 degrees). During a storm, two of my Maples snapped about 30 feet above ground level (but down the slope) and one lay over horizontal, and was suspended there 20 feet above ground by snagging other trees. The traditional term for that 30 foot length of tree in this area is called a "widow maker." On its way down, it hit my wire, ripped the box off the post, yanked the coax along until it strained my house connection and broke the coax connection there. After the storm, I hove the wire over the widow maker, confirmed the 1/16th inch nylon withstood the strain (who wulda thought?) and repaired the stripped BNC house connection. Amazingly only the ground wire to the radial field broke when the box started to fly. We get messages here from those who agonize about setting the woods on fire - never happened to me, and I never worried about it. 73's Richard Clark, KB7QHC |
Need help... End-fed, long wire or ????
Hi Denny, thanks again for the help... I guess I should expand a bit.. I'm
not just thinking of a manual tuner, but also an auto tuner, like used Triton, SGC or Icom marine/military type, so I sometimes get my wires crossed. I've read about a lot of folks using ladder line and such to feed the antenna and that was also a question. For the longwire originating in the shack, I've played with that setup before when testing radios I sell, and it really plays havoc with my electronics and computers, so I may just forego the whole manual tuner thing completely. I'd prefer to find a way to feed with coax if possible. thanks! Woody "Denny" wrote in message ups.com... Woody, you have received plenty of advice... Let me simplify if I may.. The tuner has to sit within reach usually, so that means the end of the long wire drops down into the shack to the tuner, no coax involved... No baluns, etc. are needed or advised... On certain bands the case of the antenna tuner is likely to bite you when you touch it and the rig also The cure for this is to run a quarter wave radial for each band from the ground terminal of the tuner... These can be run around in the room, or exit out the window and fan out on the ground can be slit into the dirt, whatever MFJ actually makes a tuner for the ground radials.. Works quite well... The purpose of the ground radial is to act as a counterpoise for the antenna currents reduces ground current losses and to move the RF peak voltage out to the end of the quarter wave radial leaving the tuner/radio at low RF potential... Don't over analyze this... Just hang your longwire, put out your ground radials, and have fun on the bands... denny / k8do |
Need help... End-fed, long wire or ????
Yup, Now there, I agree totally... thanks much for the help!
rb "John Ferrell" wrote in message ... On Tue, 10 Jul 2007 04:19:44 -0700, Denny wrote: Woody, you have received plenty of advice... Let me simplify if I may.. The tuner has to sit within reach usually, so that means the end of the long wire drops down into the shack to the tuner, no coax involved... No baluns, etc. are needed or advised... On certain bands the case of the antenna tuner is likely to bite you when you touch it and the rig also The cure for this is to run a quarter wave radial for each band from the ground terminal of the tuner... The SGC-237 keeps the bite outside with the antenna. No RF in the shack! It does need a source of 12 Volts to power it. There may be less expensive auto tuners but I am really tired of having to buy cheaper models only to eventually buy the top of the line... John Ferrell W8CCW "Life is easier if you learn to plow around the stumps" |
Need help... End-fed, long wire or ????
On Jul 10, 11:14 am, "Woody" wrote:
Hi Denny, thanks again for the help... I guess I should expand a bit.. I'm not just thinking of a manual tuner, but also an auto tuner, like used Triton, SGC or Icom marine/military type, Well, with the remote autotuner you will have less RF in the shack... But even then I would hang ground radials off the tuner case to keep it at lower voltage potentials... Since you are willing to spring for an SGC, etc. given your description of your site I would think about an off center fed wire antenna... Run your longwire through the trees... Roughly an 1/8 wave lowest band back from one end of the antenna drop a vertical wire to the ground and use the tuner to feed the end of the drop wire... A ground stake and some radials and you are likely to be in business... You can fool with snipping a bit off the long end of the wire if one of the bands gives the tuner a hard time... This should play... Now, ALL the tuners you mentioned and I know of are single ended, i.e. are not truely balanced for balanced feed line and putting a "balun" on the end of the ladder line does not make it a balanced tuner... Now, I use open wire feed for the majority of my antennas, but I build my own balanced tuners and open wire... cheers ... denny |
Need help... End-fed, long wire or ????
Well, with the remote autotuner you will have less RF in the shack...
But even then I would hang ground radials off the tuner case to keep it at lower voltage potentials... Definitely! One of the characteristics of the SGC autotuners is that they seem to *require* a really good RF ground. Their tuning circuitry "wants" to work into a ground connection which has a lower impedance than the wire. SGC's manual makes this point repeatedly, and identifies "grounding problems" (poor bonding, high inductance, etc.) as the commonest cause of "Hey, this thing won't tune" problems with their autotuners. My own experience with a used, older-model SGC 230 (so old it's in a non-waterproof metal case) seems to back this up. When used with a relatively simple ground, the tuner has serious problems in achieving a match, and frequently won't ever find one. I tend to think that these arbitrary-wire tuners work best in their original environment - bolted to a really big, solid chunk of metal such as a ship body or a tank. Another "gotcha" - the tuner I have, at least, can become seriously "confused" if you try to use it with a radio that has aggressive "high SWR power reduction" circuitry to protect the finals. In such a radio (my Kenwood TS-2000 is one), the output power jumps around a lot as the autotuner tries different L-network match settings, and the tuner firmware seems to misinterpret these transmitter power changes and never actually finds a low-SWR match. The same tuner, and the same wire and grounding setup, will often match within a few seconds when power is applied from another transmitter which doesn't alter its output power so abruptly (e.g. a Ten-Tec Scout 555). I've given up trying to use my old SGC-230 - it's so quirky that I just can't depend on it to work acceptably in my environment, with my radio. Other vendors' autotuners may be less of a problem in this respect. Since you are willing to spring for an SGC, etc. given your description of your site I would think about an off center fed wire antenna... Run your longwire through the trees... Roughly an 1/8 wave lowest band back from one end of the antenna drop a vertical wire to the ground and use the tuner to feed the end of the drop wire... A ground stake and some radials and you are likely to be in business... I'd recommend following SGC's recommendations... which probably add up to "lots of heavy radials". -- Dave Platt AE6EO Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
Need help... End-fed, long wire or ????
Yeah, I noticed the same thing with the motorola triton, another antique....
maybe the newer ones aren't so quirky? W "Dave Platt" wrote in message ... Well, with the remote autotuner you will have less RF in the shack... But even then I would hang ground radials off the tuner case to keep it at lower voltage potentials... Definitely! One of the characteristics of the SGC autotuners is that they seem to *require* a really good RF ground. Their tuning circuitry "wants" to work into a ground connection which has a lower impedance than the wire. SGC's manual makes this point repeatedly, and identifies "grounding problems" (poor bonding, high inductance, etc.) as the commonest cause of "Hey, this thing won't tune" problems with their autotuners. My own experience with a used, older-model SGC 230 (so old it's in a non-waterproof metal case) seems to back this up. When used with a relatively simple ground, the tuner has serious problems in achieving a match, and frequently won't ever find one. I tend to think that these arbitrary-wire tuners work best in their original environment - bolted to a really big, solid chunk of metal such as a ship body or a tank. Another "gotcha" - the tuner I have, at least, can become seriously "confused" if you try to use it with a radio that has aggressive "high SWR power reduction" circuitry to protect the finals. In such a radio (my Kenwood TS-2000 is one), the output power jumps around a lot as the autotuner tries different L-network match settings, and the tuner firmware seems to misinterpret these transmitter power changes and never actually finds a low-SWR match. The same tuner, and the same wire and grounding setup, will often match within a few seconds when power is applied from another transmitter which doesn't alter its output power so abruptly (e.g. a Ten-Tec Scout 555). I've given up trying to use my old SGC-230 - it's so quirky that I just can't depend on it to work acceptably in my environment, with my radio. Other vendors' autotuners may be less of a problem in this respect. Since you are willing to spring for an SGC, etc. given your description of your site I would think about an off center fed wire antenna... Run your longwire through the trees... Roughly an 1/8 wave lowest band back from one end of the antenna drop a vertical wire to the ground and use the tuner to feed the end of the drop wire... A ground stake and some radials and you are likely to be in business... I'd recommend following SGC's recommendations... which probably add up to "lots of heavy radials". -- Dave Platt AE6EO Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
Need help... End-fed, long wire or ????
Geez, thanks for all the help, please keep it rollin' !
w "Denny" wrote in message ups.com... On Jul 10, 11:14 am, "Woody" wrote: Hi Denny, thanks again for the help... I guess I should expand a bit.. I'm not just thinking of a manual tuner, but also an auto tuner, like used Triton, SGC or Icom marine/military type, Well, with the remote autotuner you will have less RF in the shack... But even then I would hang ground radials off the tuner case to keep it at lower voltage potentials... Since you are willing to spring for an SGC, etc. given your description of your site I would think about an off center fed wire antenna... Run your longwire through the trees... Roughly an 1/8 wave lowest band back from one end of the antenna drop a vertical wire to the ground and use the tuner to feed the end of the drop wire... A ground stake and some radials and you are likely to be in business... You can fool with snipping a bit off the long end of the wire if one of the bands gives the tuner a hard time... This should play... Now, ALL the tuners you mentioned and I know of are single ended, i.e. are not truely balanced for balanced feed line and putting a "balun" on the end of the ladder line does not make it a balanced tuner... Now, I use open wire feed for the majority of my antennas, but I build my own balanced tuners and open wire... cheers ... denny |
Need help... End-fed, long wire or ????
In article imYki.1884$YH3.394@trnddc08, "Woody"
wrote: Yeah, I noticed the same thing with the motorola triton, another antique.... maybe the newer ones aren't so quirky? W Interesting you should notice that. The original Binary Switch Lump Constant Autotuners were those designed for the Triton Series MF/HF SSB Radio's, from Motorola, by Bill Schilb. When he left Motorola and came west, to Northern Radio in Seattle, he brought that technology with him and introduced it to the MF/HF Marine Market. First at Northern, which never did anything with it, and then on to SEA, thru the ex-Northern Engineering Team, that followed Dick Stephens, from Northern, to SEA, as Northern was sinking into oblivian. The first Marine Product with this technology, was the SEA-1601 Autotuner, Designed by Bill Forgey, and Mark Johnson. A sucsession of improvments followed culminating in the SEA-1612B Autotuner. This is the model that SGC copied, for their original product, including the Firmware that still had the SEA Copyright, compiled in the code. Most of the later Binary Switched Autotuners are, either Copied, or Reverse Engineered, adaptations of the SEA1612B System. All these tuners NEED a Low Impedance RF Ground to work against, as well as a Longwire who's length is SPECIFICALLY set up to put the 1/2 Wavelength Point in a non used portion of the Spectrum. They will NOT tune within 2% of the Natural 1/2 Wavelenth point of the Longwire connected, where Antenna Impedances near Infinity. There has been considerable work done, over the years, on making this type tuner, drive Balanced Antennas. Some have used a 4:1 Balun, directly across the tuner Output, with limited sucess. Some have decoupled the Tuner from it's Coaxial Feedline, Power, and Tuner Indicator Lines, by running them thru a Bifilar Wound Torroid at the Tuner end, and then putting the tuner in the Center of a Dipole cut for the Lowest Desired Frequency of the System. This type has proved a better system than the Balun, but I have used both at Limited Coast Stations thruout Alaska, and most are still in operation today. G & L Marine Radio in Seattle, once designed an SEA-1612B based Autotuner that had two Tuner boards, one for each side of the Balanced Antenna, that ran off a single MCPU and Detector System, and just latched the same Data into both boards. I never actually heard how well Don Sr. got it to work, but always thought that it was an interesting concept. Bruce in alaska -- add a 2 before @ |
Need help... End-fed, long wire or ????
Most of the later Binary
Switched Autotuners are, either Copied, or Reverse Engineered, adaptations of the SEA1612B System. Copied or reverse engineered might be a bit harsh.. The idea of a automatically driven LC tuner has been around a while, with DC motors, servos, or steppers. Once you have the concept of a variable L or C that's "remote controlled" using a binary switched array is a pretty obvious thing to try. (e.g. I built a binary switched power inductor for ballasting a tesla coil to replace the more traditional sliding core inductor or variac with a cut core, and I doubt I was the first to think about it.) I think the subtle details in SEA's, SGC's, LDG's, or MFJ's tuners would deal more with the means of detecting the mismatch and the actual tuning algorithm. From that standpoint, the SGC and LDG tuners (which are the two I'm most familiar with) are quite different. SGC uses a pi net, LDG uses L net with cap switched between in or out. SGC and LDG use different bridge and detector designs. I'm pretty sure, also, that the actual tuning sequence is different, just based on the sounds they make. |
Need help... End-fed, long wire or ????
Well.. a million thanks for that. Quite a cool history lesson as well. So
now I'm looking for an SEA tuner... LOL... Listen, that all makes perfect sense but just to clarify, a.) now I know why that triton did so poorly when tested. We calc'd 1/2 wavelength for the longwire, and b.) Again, for continuity and clarity of this thread for future surfers...... what then, considering our discussed auto-tuners, would be the optimal length for a longwire that would be used for amateur/MARS, 3-30MHz? Pick 1/2wavelength on say 2.8Mhz and just cut it? Or calc 1/2wavelength on the lowest and add 5% or some arbitrary odd number?? Which plan will offer the least chance of dropping a 1/2wl further up the band on a desired frequency? thanks, Woody "Bruce in Alaska" wrote in message ... In article imYki.1884$YH3.394@trnddc08, "Woody" wrote: Yeah, I noticed the same thing with the motorola triton, another antique.... maybe the newer ones aren't so quirky? W Interesting you should notice that. The original Binary Switch Lump Constant Autotuners were those designed for the Triton Series MF/HF SSB Radio's, from Motorola, by Bill Schilb. When he left Motorola and came west, to Northern Radio in Seattle, he brought that technology with him and introduced it to the MF/HF Marine Market. First at Northern, which never did anything with it, and then on to SEA, thru the ex-Northern Engineering Team, that followed Dick Stephens, from Northern, to SEA, as Northern was sinking into oblivian. The first Marine Product with this technology, was the SEA-1601 Autotuner, Designed by Bill Forgey, and Mark Johnson. A sucsession of improvments followed culminating in the SEA-1612B Autotuner. This is the model that SGC copied, for their original product, including the Firmware that still had the SEA Copyright, compiled in the code. Most of the later Binary Switched Autotuners are, either Copied, or Reverse Engineered, adaptations of the SEA1612B System. All these tuners NEED a Low Impedance RF Ground to work against, as well as a Longwire who's length is SPECIFICALLY set up to put the 1/2 Wavelength Point in a non used portion of the Spectrum. They will NOT tune within 2% of the Natural 1/2 Wavelenth point of the Longwire connected, where Antenna Impedances near Infinity. There has been considerable work done, over the years, on making this type tuner, drive Balanced Antennas. Some have used a 4:1 Balun, directly across the tuner Output, with limited sucess. Some have decoupled the Tuner from it's Coaxial Feedline, Power, and Tuner Indicator Lines, by running them thru a Bifilar Wound Torroid at the Tuner end, and then putting the tuner in the Center of a Dipole cut for the Lowest Desired Frequency of the System. This type has proved a better system than the Balun, but I have used both at Limited Coast Stations thruout Alaska, and most are still in operation today. G & L Marine Radio in Seattle, once designed an SEA-1612B based Autotuner that had two Tuner boards, one for each side of the Balanced Antenna, that ran off a single MCPU and Detector System, and just latched the same Data into both boards. I never actually heard how well Don Sr. got it to work, but always thought that it was an interesting concept. Bruce in alaska -- add a 2 before @ |
Need help... End-fed, long wire or ????
In article t3ali.3392$Y_3.570@trnddc04, Woody wrote:
Well.. a million thanks for that. Quite a cool history lesson as well. So now I'm looking for an SEA tuner... LOL... Listen, that all makes perfect sense but just to clarify, a.) now I know why that triton did so poorly when tested. We calc'd 1/2 wavelength for the longwire, and b.) Again, for continuity and clarity of this thread for future surfers...... what then, considering our discussed auto-tuners, would be the optimal length for a longwire that would be used for amateur/MARS, 3-30MHz? Pick 1/2wavelength on say 2.8Mhz and just cut it? Or calc 1/2wavelength on the lowest and add 5% or some arbitrary odd number?? Which plan will offer the least chance of dropping a 1/2wl further up the band on a desired frequency? I think you'll need to run a a simple calculation, based on the frequencies you actually want to use. What you'll want, is a wire whose length is not particularly close to any multiple of 1/2 wavelength, on any frequency you want to use. A wire which would match easily on 80 meters (e.g. 1/4 wavelength long) would be a bad choice if you want to work on 40 meters as well, as it'd be 1/2 wavelength long. A simple program or spreadsheet ought to be able to do the necessary calculations... try every wire length from 66 feet to 132 feet and see if you can find a length which is a comfortable percentage away from an even multiple of 1/2 wavelength on each frequency. Or, alternatively, iterate through each frequency, calculate the 1/2-wavelength multiples, and "blacklist" every possible length which is too close to these multiples. For what it's worth, SGC sells a longwire antenna 60' in length, which they say works well on both lower and higher HF bands. It might or might not be a good choice for MARS frequencies. -- Dave Platt AE6EO Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
Need help... End-fed, long wire or ????
Bruce in Alaska wrote in
: Bruce, An interesting post overall, but ... System. All these tuners NEED a Low Impedance RF Ground to work against, as well as a Longwire who's length is SPECIFICALLY set up to put the 1/2 Wavelength Point in a non used portion of the Spectrum. They will NOT tune within 2% of the Natural 1/2 Wavelenth point of the Longwire connected, where Antenna Impedances near Infinity. The "rules" above are offered without definition or explanation, so they don't really raise the art. Manufacturer's "rules" and explanations are often inconsistent. For example, some state a minimum length that can be tuned on say 3.6MHz, and it is often around 3m, yet they rabbit on about avoiding half wave resonances in the wire to avoid high voltage at the feed point. The feed point voltage on a 3m whip at 3.6MHz is likely to be much higher than a 10m whip at its first parallel resonance. Owen |
Need help... End-fed, long wire or ????
|
Need help... End-fed, long wire or ????
Dave Platt wrote:
In article t3ali.3392$Y_3.570@trnddc04, Woody wrote: Well.. a million thanks for that. Quite a cool history lesson as well. So now I'm looking for an SEA tuner... LOL... Listen, that all makes perfect sense but just to clarify, a.) now I know why that triton did so poorly when tested. We calc'd 1/2 wavelength for the longwire, and b.) Again, for continuity and clarity of this thread for future surfers...... what then, considering our discussed auto-tuners, would be the optimal length for a longwire that would be used for amateur/MARS, 3-30MHz? Pick 1/2wavelength on say 2.8Mhz and just cut it? Or calc 1/2wavelength on the lowest and add 5% or some arbitrary odd number?? Which plan will offer the least chance of dropping a 1/2wl further up the band on a desired frequency? I think you'll need to run a a simple calculation, based on the frequencies you actually want to use. What you'll want, is a wire whose length is not particularly close to any multiple of 1/2 wavelength, on any frequency you want to use. A wire which would match easily on 80 meters (e.g. 1/4 wavelength long) would be a bad choice if you want to work on 40 meters as well, as it'd be 1/2 wavelength long. A simple program or spreadsheet ought to be able to do the necessary calculations... try every wire length from 66 feet to 132 feet and see if you can find a length which is a comfortable percentage away from an even multiple of 1/2 wavelength on each frequency. Or, alternatively, iterate through each frequency, calculate the 1/2-wavelength multiples, and "blacklist" every possible length which is too close to these multiples. For what it's worth, SGC sells a longwire antenna 60' in length, which they say works well on both lower and higher HF bands. It might or might not be a good choice for MARS frequencies. The other strategy is to use two wires of appropriately different lengths connected together at the feedpoint. (the SGC whips do this, for instance).. Space the wires some distance apart (a few inches would do).. What this does is put multiple bumps in the impedance curve and eliminates the pathological cases where you have very high Z when the (one) wire is a half wavelength or multiple thereof. At those frequencies where one wire *is* a half wavelength, and presents a high Z, the other one is likely NOT a multiple of a half wavelength, and so, will present a reasonable impedance. Sure, they interact (as folks making multiband dipoles find when trying to cut and trim), but all that really does is shift the resonances around. An interesting question would be what is the optimum ratio of lengths.. probably something like 1:1.618 or 1:2.7183 |
Need help... End-fed, long wire or ????
Owen Duffy wrote:
Bruce in Alaska wrote in : Bruce, An interesting post overall, but ... System. All these tuners NEED a Low Impedance RF Ground to work against, as well as a Longwire who's length is SPECIFICALLY set up to put the 1/2 Wavelength Point in a non used portion of the Spectrum. They will NOT tune within 2% of the Natural 1/2 Wavelenth point of the Longwire connected, where Antenna Impedances near Infinity. The "rules" above are offered without definition or explanation, so they don't really raise the art. Manufacturer's "rules" and explanations are often inconsistent. For example, some state a minimum length that can be tuned on say 3.6MHz, and it is often around 3m, yet they rabbit on about avoiding half wave resonances in the wire to avoid high voltage at the feed point. The feed point voltage on a 3m whip at 3.6MHz is likely to be much higher than a 10m whip at its first parallel resonance. there's a goodly amount of empiricism in these rules of thumb from the mfr, too. If you start to analyze it, there's all sorts of issues that crop up in the analysis: the heating and/or breakdown of the Ls and Cs inside the box, for instance (and, because it's a binary sequence with components with 20% tolerance, the voltages (for L) or currents (for C) don't divide evenly... the big Cs take more of the current than the small ones). And then, there's the whole thermal management issue, and "real ratings" of the component vs catalog vs derating. The tesla coil folks regularly run low ESR extended foil polypropylene capacitors (typical 0.15 uF at 2kV) at 2 or 3 times rated voltage at a few hundred kHz, as long as the rms current is within bounds. But they benefit from a fair amount of destructive testing and failure analysis by a coiling hobbyist with access to the appropriate gear. Owen |
Need help... End-fed, long wire or ????
In article , Owen Duffy wrote: A simple program or spreadsheet ought to be able to do the necessary calculations... try every wire length from 66 feet to 132 feet and see if you can find a length which is a comfortable percentage away from an even multiple of 1/2 wavelength on each frequency. Or, You probably mean't any integral multiple of a half wave. You're right... integral multiple of a half-wavelength, or even multiples of a quarter-wavelength are two alternative ways for stating the lengths to be avoided (high feedpoint Z). alternatively, iterate through each frequency, calculate the 1/2-wavelength multiples, and "blacklist" every possible length which is too close to these multiples. I have done just that, and searched for "sweet" wire lengths that aren't within say 5% of band edge for all HF bands. It sounds like a solution to the problem doesn't it. (5% implies that you have a pretty determinate scenario, which is a big assumption. IIRC 10%+ will not give a practical result on the higher bands.) Problem is that it probably unecessarily constrains the solution. Entirely possible! The input impedance and the feed point voltage of an end fed wire at its higher parallel resonances falls, so that whilst you might want to avoid the first such resonance, the impedance (and feed point voltage) at the third or higher resonance might well be low enough to not worry about it. And, even if it was a bit high, you might not need to be more than a couple of percent away from it to get it down to a length that might work. Odds are that some amount of experimentation is going to be required, at any given installation, to find a wire length which tunes up well with these ATUs. The orientation of the wire (vertical, inverted-L, etc.), height about ground, presence of trees and metallic objects, and (perhaps most importantly) the details of the ATU's grounding system, are likely to change the impedances around enough to make the "textbook" answers less than completely effective. -- Dave Platt AE6EO Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
Need help... End-fed, long wire or ????
Hi Owen. 5% was just a number picked out at random by me for clarification
of my question. So you wouldn't want to share your 'sweet' findings, would you?? thanks! W "Owen Duffy" wrote in message ... I have done just that, and searched for "sweet" wire lengths that aren't within say 5% of band edge for all HF bands. It sounds like a solution to the problem doesn't it. (5% implies that you have a pretty determinate scenario, which is a big assumption. IIRC 10%+ will not give a practical result on the higher bands.) Owen |
Need help... End-fed, long wire or ????
"Woody" wrote in news:hYdli.29709$BT3.8034@trnddc06:
Hi Owen. 5% was just a number picked out at random by me for clarification of my question. So you wouldn't want to share your 'sweet' findings, would you?? thanks! W, I have had a quick look for the spreadsheet and Perl scripts, but haven't found them. I am sure I have them, but haven't filed them in an ordered way apparently, I think that technically is lost... or galloping senility. The reason I didn't publish them as is at the time is is that they are an incomplete picture. Have a look at the article at http://www.vk1od.net/InvertedL/InvertedL.htm which describes an InvertedL at approximately one of those "sweet" lengths (~26m). In fact, the length was juggled to avoid excessive feedpoint voltage on all bands. Another of the "sweet" lengths is half that at 13m, and the voltage plot is rougly scaled proportionately in frequency. You will see from Fig 1 that the voltage peaks at higher frequency parallel resonances are less an issue than the first and second resonances (you can't see from the graphs, but ~10kV and 3kV respectively). Of course, none of this discussion addresses the pattern issues at the higher frequencies. As far as the earth system goes, it impacts efficiency of the system. It is my view that the earth only needs to be good enough that its loss is an acceptably low portion of the transmitter power. The shorter the radiator in wavelengths, the lower its Rr and therefore the lower the earth resistance for comparable efficiency. If you look at Fig 4 of the article, you will see that Rr is 100 ohms or greater above 5MHz, so the loss of an earth system resistance of say 30 ohms is near insignificant, but at 80m where the length is relatively short, you need a better earth for good efficiency. Don't agonise over it too much, and treat the Rules of Thumb as ROT until you understand the underlying assumptions and caveats. Owen W "Owen Duffy" wrote in message ... I have done just that, and searched for "sweet" wire lengths that aren't within say 5% of band edge for all HF bands. It sounds like a solution to the problem doesn't it. (5% implies that you have a pretty determinate scenario, which is a big assumption. IIRC 10%+ will not give a practical result on the higher bands.) Owen |
Need help... End-fed, long wire or ????
"Woody" wrote in news:hYdli.29709$BT3.8034@trnddc06:
Hi Owen. 5% was just a number picked out at random by me for clarification of my question. So you wouldn't want to share your 'sweet' findings, would you?? thanks! I had a dig around through a few thousand spreadsheets... and found it. 9.05m, 12.6m, 18.3m, 26.4m, 33.3m, 44.9m. If you want to cover 60m, leave the 26.4 out of the list. Did someone mention 60' (18.3m), it is in the list, but it is more critical than 26.4 or 12.6. As noted in my earlier post, if you want to be 10% or more away from n half waves on all bands, there is no solution. These calcs don't consider proximity of objects that may shift the tuning. My advice still stands that the higher order parallel resonances aren't such an issue, so this method unnecessarily constrains the solution.. Owen |
Need help... End-fed, long wire or ????
Yes, the history of the autotuners is fascinating...
The discussion of integral half waves, parallel resonance impedences, ground impedences, etc., is meat and potatos for antenna freaks like me... BTW, in the older ARRL handbooks is a table of guy wire lengths (for towers) that avoid resonances in the ham bands... Those lengths would make an excellent guide for the length of a random wire antenna... It might also be in the new editions, but I haven't looked at one in recent years.. Anyway, that table will give you a good starting point... B U T , what I want you to do is to simply either cobble up an L match, or pick up a tuner (any tuner, automatic or not), run some wire any length through those trees, and get on the air! If the tuner has problems with any particular band, change the length of the wire by 4 to 12 feet until it tunes OK... Once you have a working antenna you can spend time and energy gilding the lily with just the 'perfect' length and configuration... Don't waste time over analyzing - pick a tuner, throw up some wire and ground radials, and operate... A local ham who lives in a trailor park is closing in on 300 countries confirmed and his only antenna for all this is a single multiband vertical, 21 feet tall, disguised as a flag pole... Just do it... cheers ... denny |
Need help... End-fed, long wire or ????
In article t3ali.3392$Y_3.570@trnddc04, "Woody"
wrote: Well.. a million thanks for that. Quite a cool history lesson as well. So now I'm looking for an SEA tuner... LOL... Listen, that all makes perfect sense but just to clarify, a.) now I know why that triton did so poorly when tested. We calc'd 1/2 wavelength for the longwire, and b.) Again, for continuity and clarity of this thread for future surfers...... what then, considering our discussed auto-tuners, would be the optimal length for a longwire that would be used for amateur/MARS, 3-30MHz? Pick 1/2wavelength on say 2.8Mhz and just cut it? Or calc 1/2wavelength on the lowest and add 5% or some arbitrary odd number?? Which plan will offer the least chance of dropping a 1/2wl further up the band on a desired frequency? thanks, Woody What we did, is to try and have a Longwire with a 1/4 Wave Point near the lowest Operating Frequency like for the 2006Khz Alaska Private Fixed Frequency, then calculate the Natural 1/2 Wave Point for that Wire, then adjust the 1/4 Wave Length, SHORTER, until the 1/2 Wave Point DeadBand (2.5% or so) was in a part of the speectrum the Station wasn't Licensed for, Marine and Alaska Private Fixed have specific Channels, and Bands in the MF/HF Spectrum, and it isn't to hard to move the DeadBand to a nonused portion of the Spectrum. For the HAMS, that want a "Do everything, cover the whole Dc to Light Spectrum, with one Longwire Tunter", the answer is "Design and Build your own Dam Tuner with an integrate Longwire Switch and put up Multiple lengths of wire", because there isn't a product out there, that I am aware, of that does this, YET.... Bruce in alaska -- add a 2 before @ |
Need help... End-fed, long wire or ????
On Jul 9, 2:16 am, Richard Clark wrote:
Anything more convoluted is unlikely to give you more performance. 73's Richard Clark, KB7QHC Hi, Richard: Should you check with your legal counsel before you make that statement? Bill |
Need help... End-fed, long wire or ????
Hey, I'm just learning and absorbing so anything new is a place for me to
start. Thanks again! woody "Owen Duffy" wrote in message ... "Woody" wrote in news:hYdli.29709$BT3.8034@trnddc06: Hi Owen. 5% was just a number picked out at random by me for clarification of my question. So you wouldn't want to share your 'sweet' findings, would you?? thanks! I had a dig around through a few thousand spreadsheets... and found it. 9.05m, 12.6m, 18.3m, 26.4m, 33.3m, 44.9m. If you want to cover 60m, leave the 26.4 out of the list. Did someone mention 60' (18.3m), it is in the list, but it is more critical than 26.4 or 12.6. As noted in my earlier post, if you want to be 10% or more away from n half waves on all bands, there is no solution. These calcs don't consider proximity of objects that may shift the tuning. My advice still stands that the higher order parallel resonances aren't such an issue, so this method unnecessarily constrains the solution.. Owen |
Need help... End-fed, long wire or ????
Yep, amen to that! LOL...
woody "Denny" wrote in message ups.com... Yes, the history of the autotuners is fascinating... The discussion of integral half waves, parallel resonance impedences, ground impedences, etc., is meat and potatos for antenna freaks like me... BTW, in the older ARRL handbooks is a table of guy wire lengths (for towers) that avoid resonances in the ham bands... Those lengths would make an excellent guide for the length of a random wire antenna... It might also be in the new editions, but I haven't looked at one in recent years.. Anyway, that table will give you a good starting point... B U T , what I want you to do is to simply either cobble up an L match, or pick up a tuner (any tuner, automatic or not), run some wire any length through those trees, and get on the air! If the tuner has problems with any particular band, change the length of the wire by 4 to 12 feet until it tunes OK... Once you have a working antenna you can spend time and energy gilding the lily with just the 'perfect' length and configuration... Don't waste time over analyzing - pick a tuner, throw up some wire and ground radials, and operate... A local ham who lives in a trailor park is closing in on 300 countries confirmed and his only antenna for all this is a single multiband vertical, 21 feet tall, disguised as a flag pole... Just do it... cheers ... denny |
Need help... End-fed, long wire or ????
LOL, and then there's that....
also a great idea! thanks much! Woody "Bruce in Alaska" wrote in message ... In article t3ali.3392$Y_3.570@trnddc04, "Woody" wrote: Well.. a million thanks for that. Quite a cool history lesson as well. So now I'm looking for an SEA tuner... LOL... Listen, that all makes perfect sense but just to clarify, a.) now I know why that triton did so poorly when tested. We calc'd 1/2 wavelength for the longwire, and b.) Again, for continuity and clarity of this thread for future surfers...... what then, considering our discussed auto-tuners, would be the optimal length for a longwire that would be used for amateur/MARS, 3-30MHz? Pick 1/2wavelength on say 2.8Mhz and just cut it? Or calc 1/2wavelength on the lowest and add 5% or some arbitrary odd number?? Which plan will offer the least chance of dropping a 1/2wl further up the band on a desired frequency? thanks, Woody What we did, is to try and have a Longwire with a 1/4 Wave Point near the lowest Operating Frequency like for the 2006Khz Alaska Private Fixed Frequency, then calculate the Natural 1/2 Wave Point for that Wire, then adjust the 1/4 Wave Length, SHORTER, until the 1/2 Wave Point DeadBand (2.5% or so) was in a part of the speectrum the Station wasn't Licensed for, Marine and Alaska Private Fixed have specific Channels, and Bands in the MF/HF Spectrum, and it isn't to hard to move the DeadBand to a nonused portion of the Spectrum. For the HAMS, that want a "Do everything, cover the whole Dc to Light Spectrum, with one Longwire Tunter", the answer is "Design and Build your own Dam Tuner with an integrate Longwire Switch and put up Multiple lengths of wire", because there isn't a product out there, that I am aware, of that does this, YET.... Bruce in alaska -- add a 2 before @ |
Need help... End-fed, long wire or ????
On Fri, 13 Jul 2007 16:56:57 -0700, Bill wrote:
On Jul 9, 2:16 am, Richard Clark wrote: Anything more convoluted is unlikely to give you more performance. Should you check with your legal counsel before you make that statement? Talk about convolution. Plug your legal counsel in and see if DX pegs the S-Meter. 73's Richard Clark, KB7QHC |
Need help... End-fed, long wire or ????
In article ,
Richard Clark wrote: Talk about convolution. Plug your legal counsel in and see if DX pegs the S-Meter. 73's Richard Clark, KB7QHC No, Legal Counsel type folks are just one step Up the ladder from Politicos, and they are only good for starting Diesel Engines in very cold weather. Lots of HOT AIR, coming out of those guys..... but how to get them to Blow it down the Intake Manifold..... Bruce in alaska -- add a 2 before @ |
Need help... End-fed, long wire or ????
"Denny" wrote in message ups.com... snip Don't waste time over analyzing - pick a tuner, throw up some wire and ground radials, and operate... A local ham who lives in a trailor park is closing in on 300 countries confirmed and his only antenna for all this is a single multiband vertical, 21 feet tall, disguised as a flag pole... Just do it... Yup. I'm on HF with a $50.00 used transceiver, a $5.00 pi-network tuner, some coax, a balun and two pieces of copper pipe laying on my roof. It ain't purty but I'm talking to people and they're talking back. "Sal" |
Need help... End-fed, long wire or ????
You guys crack me up. The poor guy wanted a simple longwire solution.
I want one too, and that's how I found this thread. I read in W1FB's Antenna Notebook that you can take a 1 wavelength piece of wire, feed it with 75 Ohm coax 1/4 wavelength in from one end, with the hot side going to the 3/4 wavelength piece and the shield going to the 1/4 wavelength piece. It looks like you don't need any type of tuner. Has anybody tried that? I'm looking for a simple antenna for PSK-31 QRP that the homeowners association won't even see, and this looks like the deal, but I can't find any corroboration for the concept. Dave Morris N5UP www.eQSL.cc |
Need help... End-fed, long wire or ????
In article om,
wrote: I read in W1FB's Antenna Notebook that you can take a 1 wavelength piece of wire, feed it with 75 Ohm coax 1/4 wavelength in from one end, with the hot side going to the 3/4 wavelength piece and the shield going to the 1/4 wavelength piece. It looks like you don't need any type of tuner. Has anybody tried that? I'm looking for a simple antenna for PSK-31 QRP that the homeowners association won't even see, and this looks like the deal, but I can't find any corroboration for the concept. That sounds like a form of off-center-fed resonant doublet. Since the radiator is 1 wavelength long, it will have current maxima 1/4 away from each end (which is where you're feeding it). I'd guess that it will provide a reasonable (although imperfect) match to a 75-ohm coax... you might see an SWR of 2:1 or so on the coax. The impedance seen by the rig will depend on the length of the feedline, and a rig designed to drive a 50-ohm load might see a fairly low SWR, or perhaps one as high as 3:1 or 4:1 (at a guess). If your rig has a built-in ATU, it's probably adequate to flatten this sort of SWR down to the point where the rig's finals are happy with it. There's likely to be some amount of RF current present on the outside of the coaxial feedline, due both to conduction at the feedpoint and to induction from the wire (since the feedline is not located symmetrically in the center of the radiating element). If this causes sufficient "RF in the shack" to be a problem, you might want to add an isolating choke where the feedline enters the building... and if there isn't enough RF in the shack to cause problems, then don't worry about it. In either case, it's probably going to be less RF-in-the-shack than you'd get with an end-fed longwire, fed against the station ground or a counterpoise. Seems like a reasonable candidate for a "stealth" antenna, if you can conceal the coax running up to the feedpoint, and use a thin-gauge wire as a radiator (e.g. thin-gauge enamel-insulated magnet wire). -- Dave Platt AE6EO Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
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