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TX Distance question
Hi Folks
I have limited experience (ok almost none really) with respect to Amateur Radio outside of the 2M band. However I just recently got my code ticket & installed a radio on my sailboat. I am using a TS-50 with an automatic tuner and a long copper wire to the top of the mast (probably 50 feet or so long). My ground plane/counterpoise consists of tying the ground to a large aluminium area in the stern of the boat with a copper foil. My very first contacts were established with 2 land stations on 14300 at 100W that were about 1000 miles away. They both reported that my signal was good and that it sounded like I was "sitting right next to them". I have no idea if this was a good distance, great, or mediocre. I realize that propogation variables prevent anyone from giving a really clear answer to this question, but in general, what sort of distance should I expect to achieve? I'm trying to decide whether I need to improve my antenna ground by adding a dynaplate (costly and requies the boat to be taken from the water for installation) or whether the range I am getting is decent. Can anyone comment? Thanks |
James wrote:
I have limited experience (ok almost none really) with respect to Amateur Radio outside of the 2M band. However I just recently got my code ticket & installed a radio on my sailboat. I am using a TS-50 with an automatic tuner and a long copper wire to the top of the mast (probably 50 feet or so long). My ground plane/counterpoise consists of tying the ground to a large aluminium area in the stern of the boat with a copper foil. My very first contacts were established with 2 land stations on 14300 at 100W that were about 1000 miles away. They both reported that my signal was good and that it sounded like I was "sitting right next to them". I have no idea if this was a good distance, great, or mediocre. I realize that propogation variables prevent anyone from giving a really clear answer to this question, but in general, what sort of distance should I expect to achieve? I'm trying to decide whether I need to improve my antenna ground by adding a dynaplate (costly and requies the boat to be taken from the water for installation) or whether the range I am getting is decent. Propagation will have a HUGE effect on your distance capability. Under good conditions your station should be able to work any point on earth. On the other hand, when the 14MHz band "goes out" (which at this point in the sunspot cycle will happen pretty much every night) you'll be lucky to work 30 miles. I think the ground you describe should be more than adequate. (many land-based mobiles settle for something MUCH, MUCH worse!) You'll need lower frequencies for nighttime operation. 7MHz and 3.5MHz. The antenna *may* (or may not) be too short for effective operation on these bands. Try it, the worst that can happen is the automatic tuner will refuse to make a match. (I think you'll probably be OK on 7, 3.5 may be a problem) Good luck! -- Doug Smith W9WI Pleasant View (Nashville), TN EM66 http://www.w9wi.com |
James wrote:
I have limited experience (ok almost none really) with respect to Amateur Radio outside of the 2M band. However I just recently got my code ticket & installed a radio on my sailboat. I am using a TS-50 with an automatic tuner and a long copper wire to the top of the mast (probably 50 feet or so long). My ground plane/counterpoise consists of tying the ground to a large aluminium area in the stern of the boat with a copper foil. My very first contacts were established with 2 land stations on 14300 at 100W that were about 1000 miles away. They both reported that my signal was good and that it sounded like I was "sitting right next to them". I have no idea if this was a good distance, great, or mediocre. I realize that propogation variables prevent anyone from giving a really clear answer to this question, but in general, what sort of distance should I expect to achieve? I'm trying to decide whether I need to improve my antenna ground by adding a dynaplate (costly and requies the boat to be taken from the water for installation) or whether the range I am getting is decent. Propagation will have a HUGE effect on your distance capability. Under good conditions your station should be able to work any point on earth. On the other hand, when the 14MHz band "goes out" (which at this point in the sunspot cycle will happen pretty much every night) you'll be lucky to work 30 miles. I think the ground you describe should be more than adequate. (many land-based mobiles settle for something MUCH, MUCH worse!) You'll need lower frequencies for nighttime operation. 7MHz and 3.5MHz. The antenna *may* (or may not) be too short for effective operation on these bands. Try it, the worst that can happen is the automatic tuner will refuse to make a match. (I think you'll probably be OK on 7, 3.5 may be a problem) Good luck! -- Doug Smith W9WI Pleasant View (Nashville), TN EM66 http://www.w9wi.com |
"Bill Turner" wrote in message ... On Fri, 26 Nov 2004 10:14:46 -0500, James wrote: I'm trying to decide whether I need to improve my antenna ground by adding a dynaplate (costly and requies the boat to be taken from the water for installation) or whether the range I am getting is decent. __________________________________________________ _______ I'd say your system is working pretty well. 50 feet is too long for a 20 meter antenna, however. Your auto tuner is correcting for it, but a shorter length will actually work better, since the auto tuner won't have to introduce as much correction and therefore will have lower loss in the tuner itself. The vertical part of a ground plane antenna (which is what you have) can be determined by the formula Feet=234/Freq, or for 14.3 MHz, 16.4 feet (rounded off). The exact footage depends on variables in the immediate environment, but that should be close enough. If you have to have a 50 foot overall wire because of the height of the boat's mast, just put an egg insulator at the 16.4 foot length to break it up. For multiple bands, figure the length of each section and put egg insulators where needed, and then to change bands, just connect a jumper wire across various eggs to get the correct length. Neat, huh? :-) Also, you can't have too much ground area, within reason. More aluminum foil or copper is always better. If you have access to an SWR analyzer such as the MFJ 259, so much the better. They are highly recommended for making and troubleshooting antennas. -- 73, Bill W6WRT Bill, 50 foot is only too long if you are sticking with the resonant length situation. Which is not really necessary with his setup. In fact he probably gets better versatility with the longer length. Just an opinion. Dan/W4NTI |
"Bill Turner" wrote in message ... On Fri, 26 Nov 2004 10:14:46 -0500, James wrote: I'm trying to decide whether I need to improve my antenna ground by adding a dynaplate (costly and requies the boat to be taken from the water for installation) or whether the range I am getting is decent. __________________________________________________ _______ I'd say your system is working pretty well. 50 feet is too long for a 20 meter antenna, however. Your auto tuner is correcting for it, but a shorter length will actually work better, since the auto tuner won't have to introduce as much correction and therefore will have lower loss in the tuner itself. The vertical part of a ground plane antenna (which is what you have) can be determined by the formula Feet=234/Freq, or for 14.3 MHz, 16.4 feet (rounded off). The exact footage depends on variables in the immediate environment, but that should be close enough. If you have to have a 50 foot overall wire because of the height of the boat's mast, just put an egg insulator at the 16.4 foot length to break it up. For multiple bands, figure the length of each section and put egg insulators where needed, and then to change bands, just connect a jumper wire across various eggs to get the correct length. Neat, huh? :-) Also, you can't have too much ground area, within reason. More aluminum foil or copper is always better. If you have access to an SWR analyzer such as the MFJ 259, so much the better. They are highly recommended for making and troubleshooting antennas. -- 73, Bill W6WRT Bill, 50 foot is only too long if you are sticking with the resonant length situation. Which is not really necessary with his setup. In fact he probably gets better versatility with the longer length. Just an opinion. Dan/W4NTI |
....Keep the 50 feet, use a tuner. Quit wasting good
'worry' on tuner losses, they don't amount to enough to worry about. The 'additional' length (and that tuner) gives you access to other bands. Will it be the 'best' possible antenna? Of course not, but it'll certainly be adequate... 'Doc |
....Keep the 50 feet, use a tuner. Quit wasting good
'worry' on tuner losses, they don't amount to enough to worry about. The 'additional' length (and that tuner) gives you access to other bands. Will it be the 'best' possible antenna? Of course not, but it'll certainly be adequate... 'Doc |
'Doc wrote:
...Keep the 50 feet, use a tuner. Quit wasting good 'worry' on tuner losses, they don't amount to enough to worry about. The 'additional' length (and that tuner) gives you access to other bands. Will it be the 'best' possible antenna? Of course not, but it'll certainly be adequate... 'Doc Thanks for the feedback folks. Doc is on the right track. THe tuner works really well (way to go SGC, nice product!) and the antenna length doesn't seem to be impeding transmission distance. Furthermore, the length, although not electrically correct for all frequencies, is convenient physically for a sail boat. Glad to hear that the 1000 mile distance I attained was acceptable performance. My actual planned use is for keeping in touch with other vessels (friends) that are within a couple of thousand miles tops. Hopefully it will do the trick. Thanks for the feedback folks. Muuch appreciated. Jimmy |
'Doc wrote:
...Keep the 50 feet, use a tuner. Quit wasting good 'worry' on tuner losses, they don't amount to enough to worry about. The 'additional' length (and that tuner) gives you access to other bands. Will it be the 'best' possible antenna? Of course not, but it'll certainly be adequate... 'Doc Thanks for the feedback folks. Doc is on the right track. THe tuner works really well (way to go SGC, nice product!) and the antenna length doesn't seem to be impeding transmission distance. Furthermore, the length, although not electrically correct for all frequencies, is convenient physically for a sail boat. Glad to hear that the 1000 mile distance I attained was acceptable performance. My actual planned use is for keeping in touch with other vessels (friends) that are within a couple of thousand miles tops. Hopefully it will do the trick. Thanks for the feedback folks. Muuch appreciated. Jimmy |
"Bill Turner" wrote in message ... On Fri, 26 Nov 2004 10:14:46 -0500, James wrote: I'm trying to decide whether I need to improve my antenna ground by adding a dynaplate (costly and requies the boat to be taken from the water for installation) or whether the range I am getting is decent. __________________________________________________ _______ I'd say your system is working pretty well. 50 feet is too long for a 20 meter antenna, however. Your auto tuner is correcting for it, but a shorter length will actually work better, since the auto tuner won't have to introduce as much correction and therefore will have lower loss in the tuner itself. The vertical part of a ground plane antenna (which is what you have) can be determined by the formula Feet=234/Freq, or for 14.3 MHz, 16.4 feet (rounded off). The exact footage depends on variables in the immediate environment, but that should be close enough. If you have to have a 50 foot overall wire because of the height of the boat's mast, just put an egg insulator at the 16.4 foot length to break it up. For multiple bands, figure the length of each section and put egg insulators where needed, and then to change bands, just connect a jumper wire across various eggs to get the correct length. Neat, huh? :-) Exactly what I was going to suggest. This will be easy to do if you have a pully on the top end so you can easily drop the wire to change the shorting straps. With the 50 foot wire, I would be concerned about getting high angle radiation on 10/15/20 metters. Dog bone insulators might put less capacitive loading on the top of the disconnected section. Tam/WB2TT Also, you can't have too much ground area, within reason. More aluminum foil or copper is always better. If you have access to an SWR analyzer such as the MFJ 259, so much the better. They are highly recommended for making and troubleshooting antennas. -- 73, Bill W6WRT |
"Bill Turner" wrote in message ... On Fri, 26 Nov 2004 10:14:46 -0500, James wrote: I'm trying to decide whether I need to improve my antenna ground by adding a dynaplate (costly and requies the boat to be taken from the water for installation) or whether the range I am getting is decent. __________________________________________________ _______ I'd say your system is working pretty well. 50 feet is too long for a 20 meter antenna, however. Your auto tuner is correcting for it, but a shorter length will actually work better, since the auto tuner won't have to introduce as much correction and therefore will have lower loss in the tuner itself. The vertical part of a ground plane antenna (which is what you have) can be determined by the formula Feet=234/Freq, or for 14.3 MHz, 16.4 feet (rounded off). The exact footage depends on variables in the immediate environment, but that should be close enough. If you have to have a 50 foot overall wire because of the height of the boat's mast, just put an egg insulator at the 16.4 foot length to break it up. For multiple bands, figure the length of each section and put egg insulators where needed, and then to change bands, just connect a jumper wire across various eggs to get the correct length. Neat, huh? :-) Exactly what I was going to suggest. This will be easy to do if you have a pully on the top end so you can easily drop the wire to change the shorting straps. With the 50 foot wire, I would be concerned about getting high angle radiation on 10/15/20 metters. Dog bone insulators might put less capacitive loading on the top of the disconnected section. Tam/WB2TT Also, you can't have too much ground area, within reason. More aluminum foil or copper is always better. If you have access to an SWR analyzer such as the MFJ 259, so much the better. They are highly recommended for making and troubleshooting antennas. -- 73, Bill W6WRT |
Bill Turner wrote:
On Sat, 27 Nov 2004 06:35:49 GMT, 'Doc wrote: Will it be the 'best' possible antenna? Of course not, but it'll certainly be adequate... 'Doc __________________________________________________ _______ More cost, less performance. Amazes me what some people think is "adequate". I'd lose the tuner and spend the money on more goodies for the boat. Oh, well. -- Bill W6WRT How about adequate performance and convenience? Ever been aboard an ocean going sail boat when the waves hit 5 meters and the wind is howling like a freight train? If not you can't imagine the fury. I've been there. It's exhilirating but not easy to endure. In fact it's damned hard work. That is NOT the time to be playing with knobs and switches trying to tune for a particular band. Believe me, I will have more imporant things to do. But I do want to know that I can tranmsit immediately if something terrible happens by just keying the mic. No fuss. No offence but I've always been intrigued watching amateur enthusiasts wiggling knobs and waggling switches. Reminds me of a scene from the wizard of oz for some reason. Seems so unnecessary in this day and age. CONVENIENCE is a VERY good a reason as any to use a tuner. And they're not all that costly either. A few hundred bucks at best. Just my 2 cents worth. Jimmy |
Bill Turner wrote:
On Sat, 27 Nov 2004 06:35:49 GMT, 'Doc wrote: Will it be the 'best' possible antenna? Of course not, but it'll certainly be adequate... 'Doc __________________________________________________ _______ More cost, less performance. Amazes me what some people think is "adequate". I'd lose the tuner and spend the money on more goodies for the boat. Oh, well. -- Bill W6WRT How about adequate performance and convenience? Ever been aboard an ocean going sail boat when the waves hit 5 meters and the wind is howling like a freight train? If not you can't imagine the fury. I've been there. It's exhilirating but not easy to endure. In fact it's damned hard work. That is NOT the time to be playing with knobs and switches trying to tune for a particular band. Believe me, I will have more imporant things to do. But I do want to know that I can tranmsit immediately if something terrible happens by just keying the mic. No fuss. No offence but I've always been intrigued watching amateur enthusiasts wiggling knobs and waggling switches. Reminds me of a scene from the wizard of oz for some reason. Seems so unnecessary in this day and age. CONVENIENCE is a VERY good a reason as any to use a tuner. And they're not all that costly either. A few hundred bucks at best. Just my 2 cents worth. Jimmy |
In article ,
Bill Turner wrote: If you're a purist, a simple L-network at the base will transform whatever impedance you have to exactly 50 ohms. L-networks of this type are quite broadbanded and one setting will usually cover the whole band. Tuners, begone! :-) -- Bill W6WRT In what world does an "L network" not equal exactly what a tuner does for a wire antenna? An autotuner is nothing more than a binary incremented L Network with autofeedback of directional power, and phase. You suggestion is the same thing with no feedback or incremental changes. Me |
In article ,
Bill Turner wrote: If you're a purist, a simple L-network at the base will transform whatever impedance you have to exactly 50 ohms. L-networks of this type are quite broadbanded and one setting will usually cover the whole band. Tuners, begone! :-) -- Bill W6WRT In what world does an "L network" not equal exactly what a tuner does for a wire antenna? An autotuner is nothing more than a binary incremented L Network with autofeedback of directional power, and phase. You suggestion is the same thing with no feedback or incremental changes. Me |
In article ,
James wrote: Thanks for the feedback folks. Doc is on the right track. THe tuner works really well (way to go SGC, nice product!) and the antenna length doesn't seem to be impeding transmission distance. Furthermore, the length, although not electrically correct for all frequencies, is convenient physically for a sail boat. Glad to hear that the 1000 mile distance I attained was acceptable performance. My actual planned use is for keeping in touch with other vessels (friends) that are within a couple of thousand miles tops. Hopefully it will do the trick. Thanks for the feedback folks. Muuch appreciated. Jimmy With a 50' antenna length and an adiquate RF Ground, one could consider that a respectable Marine Radio Installation. One thing that needs to be understood is that ALL Autotuners have a REALLY BIG difficency that is inherent in their design. They can NOT tune wires at the Half Wavelength point and 50Khz on each side. At this point antenna impedance becomes Infinite and can't be tuned. so a boater must make sure that he never intends to transmit on the frequency that is at the electrical Half Wavelength of the antenna. He may need to lengthen ot shorten the wire to adjust for this condition. Bruce in alaska -- add a 2 before @ |
In article ,
James wrote: Thanks for the feedback folks. Doc is on the right track. THe tuner works really well (way to go SGC, nice product!) and the antenna length doesn't seem to be impeding transmission distance. Furthermore, the length, although not electrically correct for all frequencies, is convenient physically for a sail boat. Glad to hear that the 1000 mile distance I attained was acceptable performance. My actual planned use is for keeping in touch with other vessels (friends) that are within a couple of thousand miles tops. Hopefully it will do the trick. Thanks for the feedback folks. Muuch appreciated. Jimmy With a 50' antenna length and an adiquate RF Ground, one could consider that a respectable Marine Radio Installation. One thing that needs to be understood is that ALL Autotuners have a REALLY BIG difficency that is inherent in their design. They can NOT tune wires at the Half Wavelength point and 50Khz on each side. At this point antenna impedance becomes Infinite and can't be tuned. so a boater must make sure that he never intends to transmit on the frequency that is at the electrical Half Wavelength of the antenna. He may need to lengthen ot shorten the wire to adjust for this condition. Bruce in alaska -- add a 2 before @ |
On Fri, 26 Nov 2004 10:14:46 -0500, James
wrote: Can anyone comment? Hi James, Well, as to the DX range, that has been responded to. So, to add to all the comments in regard to height of antenna, tuners, automatic tuners and the rest - another comment. Take a fishing reel full of the Wireman's Flex weave (no doubt this will provoke comments about wire corrosion) and drive it. Use your hoist to pull out the correct height for any band. I do take note of your admonition about fumbling with knobs, dials, switches when a rogue wave is overtaking you. Your knottage may vary. 73's Richard Clark, KB7QHC |
On Fri, 26 Nov 2004 10:14:46 -0500, James
wrote: Can anyone comment? Hi James, Well, as to the DX range, that has been responded to. So, to add to all the comments in regard to height of antenna, tuners, automatic tuners and the rest - another comment. Take a fishing reel full of the Wireman's Flex weave (no doubt this will provoke comments about wire corrosion) and drive it. Use your hoist to pull out the correct height for any band. I do take note of your admonition about fumbling with knobs, dials, switches when a rogue wave is overtaking you. Your knottage may vary. 73's Richard Clark, KB7QHC |
Bill Turner wrote:
On Sat, 27 Nov 2004 11:51:01 -0500, James wrote: Ever been aboard an ocean going sail boat when the waves hit 5 meters and the wind is howling like a freight train? If not you can't imagine the fury. I've been there. It's exhilirating but not easy to endure. In fact it's damned hard work. That is NOT the time to be playing with knobs and switches trying to tune for a particular band. __________________________________________________ _______ Your point is well taken, but this is also NOT the time for equipment failure. If that nifty tuner gets dunked with a dollop of salt water, you are dead, RF wise. The KISS principle is your friend. Anyone who can do a sail change or heave to in 5 meter waves can clip or unclip a jumper, or better yet, will have the jumper set beforehand. To each his own. -- Bill W6WRT Thanks for the words of wisdom Bill. In fact I made a point of purchasing a tuner that comes in a water tight (read that water PROOF according to the manfacturer) case. It's high up mounted in a lazerette that "theoretically" stays dry. The ground and antenna stud are both 316 Stainless (highly corrosion resistant and intended for use in salt air). Furthermore, the electrical connection between antenna stud and wire is soldered, crimped, and then heat shrunk with adhesive lined shrink. Instead of using high tension wire for the antenna connection to the backstay wire, I used tinned copper heavy gauge insulated electrical wire. The environment that I live in is so corrosive that, believe it or not I had to strip back the jacket to expose the tinned copper wire, and then seal the cut edge of the jacket to prevent salt water ingress between jacket and wire. If that isn't done even tinned copper wire will corrode. Salt water will creep under the jacket and corrosion will occur for a few feet distance from the stripped jacket. All connections (RF, power and control) between tuner and radio are made with crimp and solder, then sealed with liquid electrical tape, then adhesive lined heat shrink. I bought really big insulators to go at both ends of the wire antenna too. Salt water is conductive and the larger insulator with heavy ribbing will hopefully reduce the surface coating of salty water to a level that precludes conductivity. Hopefully. the copper wire I ran up the mast is on it's own pulley (well it will be when I find time to go up the mast) and is already a lovely shade of green. I have a spare, and hope this one lasts a year before needing replacement. Even so, I expect to have to service the connections about once a year or so. And you thought putting a beam on a tower was hard! Just thought you'd find the lengths we have to go to in the ocean environment interesting. The KISS principle is followed where ever I can too. I sincerely agree. When things go badly on board, it's rarely one big bad thing that bites ya. It's a string of small problems that...when combined, lead to a bad day. I guess that's true in a lot of endeavors come to think of it. Last time I was in a bad storm (a really bad one at that) I was on the radio seeking information from someone else who had radar (I do not). My autohelm had failed (a lousy 25 cent pin broke) and so I had to hand steer in heavy seas. I couldn't leave the wheel. Fortunately the mic on my marine VHF radio ~just~ reached the wheel from inside. Unfortunately that is when I discovered that if I pulled on the mic cable it became very intermittent. And that led to me spending a half hour trying to raise a nearby boat with radar to ask which way the storm appeared to be moving. Then the lightning started hitting the water all around me...from there...well...let's just say it went downhill some. Simple is good. Thanks again for the feedback. |
Bill Turner wrote:
On Sat, 27 Nov 2004 11:51:01 -0500, James wrote: Ever been aboard an ocean going sail boat when the waves hit 5 meters and the wind is howling like a freight train? If not you can't imagine the fury. I've been there. It's exhilirating but not easy to endure. In fact it's damned hard work. That is NOT the time to be playing with knobs and switches trying to tune for a particular band. __________________________________________________ _______ Your point is well taken, but this is also NOT the time for equipment failure. If that nifty tuner gets dunked with a dollop of salt water, you are dead, RF wise. The KISS principle is your friend. Anyone who can do a sail change or heave to in 5 meter waves can clip or unclip a jumper, or better yet, will have the jumper set beforehand. To each his own. -- Bill W6WRT Thanks for the words of wisdom Bill. In fact I made a point of purchasing a tuner that comes in a water tight (read that water PROOF according to the manfacturer) case. It's high up mounted in a lazerette that "theoretically" stays dry. The ground and antenna stud are both 316 Stainless (highly corrosion resistant and intended for use in salt air). Furthermore, the electrical connection between antenna stud and wire is soldered, crimped, and then heat shrunk with adhesive lined shrink. Instead of using high tension wire for the antenna connection to the backstay wire, I used tinned copper heavy gauge insulated electrical wire. The environment that I live in is so corrosive that, believe it or not I had to strip back the jacket to expose the tinned copper wire, and then seal the cut edge of the jacket to prevent salt water ingress between jacket and wire. If that isn't done even tinned copper wire will corrode. Salt water will creep under the jacket and corrosion will occur for a few feet distance from the stripped jacket. All connections (RF, power and control) between tuner and radio are made with crimp and solder, then sealed with liquid electrical tape, then adhesive lined heat shrink. I bought really big insulators to go at both ends of the wire antenna too. Salt water is conductive and the larger insulator with heavy ribbing will hopefully reduce the surface coating of salty water to a level that precludes conductivity. Hopefully. the copper wire I ran up the mast is on it's own pulley (well it will be when I find time to go up the mast) and is already a lovely shade of green. I have a spare, and hope this one lasts a year before needing replacement. Even so, I expect to have to service the connections about once a year or so. And you thought putting a beam on a tower was hard! Just thought you'd find the lengths we have to go to in the ocean environment interesting. The KISS principle is followed where ever I can too. I sincerely agree. When things go badly on board, it's rarely one big bad thing that bites ya. It's a string of small problems that...when combined, lead to a bad day. I guess that's true in a lot of endeavors come to think of it. Last time I was in a bad storm (a really bad one at that) I was on the radio seeking information from someone else who had radar (I do not). My autohelm had failed (a lousy 25 cent pin broke) and so I had to hand steer in heavy seas. I couldn't leave the wheel. Fortunately the mic on my marine VHF radio ~just~ reached the wheel from inside. Unfortunately that is when I discovered that if I pulled on the mic cable it became very intermittent. And that led to me spending a half hour trying to raise a nearby boat with radar to ask which way the storm appeared to be moving. Then the lightning started hitting the water all around me...from there...well...let's just say it went downhill some. Simple is good. Thanks again for the feedback. |
Bill,
In most cases, anything you do on a boat is a compromise between what it 'ought to be' and what's possible. Since the backstay (or frontstay) is ~there~ anyway, why not use it? Certainly not the 'best' thing in the world (whatever that is), but 'better' than most alternative$. Some people have a 'phobia' about tuners. If you don't want to use one, that's fine. They do make 'things' much easier and the difference in performance is 'acceptible' in most cases (acceptible being relative). Since there are alternatives, pick the one you think you can 'live' with and go with it. "You pays your money and takes your choice", as they used to say in the house with the red velvet wall paper... 'Doc PS - Not that I've ever been in one of those houses, I've just read about them... |
Bill,
In most cases, anything you do on a boat is a compromise between what it 'ought to be' and what's possible. Since the backstay (or frontstay) is ~there~ anyway, why not use it? Certainly not the 'best' thing in the world (whatever that is), but 'better' than most alternative$. Some people have a 'phobia' about tuners. If you don't want to use one, that's fine. They do make 'things' much easier and the difference in performance is 'acceptible' in most cases (acceptible being relative). Since there are alternatives, pick the one you think you can 'live' with and go with it. "You pays your money and takes your choice", as they used to say in the house with the red velvet wall paper... 'Doc PS - Not that I've ever been in one of those houses, I've just read about them... |
Oops, sorry.
The idea is to make it as 'idiot' proof as possible. That does not, and will never mean the 'best'... - 'Doc |
Oops, sorry.
The idea is to make it as 'idiot' proof as possible. That does not, and will never mean the 'best'... - 'Doc |
"'Doc" wrote in message .. . Oops, sorry. The idea is to make it as 'idiot' proof as possible. That does not, and will never mean the 'best'... - 'Doc Make something "idiot-proof" and Nature will just make a better idiot. 73 - H |
"'Doc" wrote in message .. . Oops, sorry. The idea is to make it as 'idiot' proof as possible. That does not, and will never mean the 'best'... - 'Doc Make something "idiot-proof" and Nature will just make a better idiot. 73 - H |
In article ,
James wrote: the copper wire I ran up the mast is on it's own pulley (well it will be when I find time to go up the mast) and is already a lovely shade of green. You should replace the copper wire with the stuff the BIG BOYS use. It is called Phospher/Bronze Antenna wire and it Doesn't turn green when in contact with Seawater or salt air. Stuff was designed for this spacific purpose. Bruce in alaska -- add a 2 before @ |
In article ,
James wrote: the copper wire I ran up the mast is on it's own pulley (well it will be when I find time to go up the mast) and is already a lovely shade of green. You should replace the copper wire with the stuff the BIG BOYS use. It is called Phospher/Bronze Antenna wire and it Doesn't turn green when in contact with Seawater or salt air. Stuff was designed for this spacific purpose. Bruce in alaska -- add a 2 before @ |
Bill Turner wrote:
Once the antenna is resonant, a simple L-C network will transform the impedance to 50 ohms resistive and you are all set. Simple, cheap and reliable, all the things a tuner is not. And single-banded, one thing a tuner is not. :-) The antenna need not be resonant. Under certain easily obtainable conditions, the length of the open-wire transmission line can tune a non-resonant antenna to system resonance and better the losses in the coax feeding a resonant antenna. How to do that is described on my web page. -- 73, Cecil http://www.qsl.net/w5dxp |
Bill Turner wrote:
Once the antenna is resonant, a simple L-C network will transform the impedance to 50 ohms resistive and you are all set. Simple, cheap and reliable, all the things a tuner is not. And single-banded, one thing a tuner is not. :-) The antenna need not be resonant. Under certain easily obtainable conditions, the length of the open-wire transmission line can tune a non-resonant antenna to system resonance and better the losses in the coax feeding a resonant antenna. How to do that is described on my web page. -- 73, Cecil http://www.qsl.net/w5dxp |
Back to TX distance - you really need to get a good book on propagation and
understand the solar cycle and the characteristics of each band. For example -- on 10M with the right time in the 11 year solar cycle -- a minimum antenna and a few watts will work the world (at the right time of day) On 160M in the day time in the summer with low power -- you ain't going anywhere -- The Anon Keyboard I doubt, therefore I might be "Cecil Moore" wrote in message ... Bill Turner wrote: Once the antenna is resonant, a simple L-C network will transform the impedance to 50 ohms resistive and you are all set. Simple, cheap and reliable, all the things a tuner is not. And single-banded, one thing a tuner is not. :-) The antenna need not be resonant. Under certain easily obtainable conditions, the length of the open-wire transmission line can tune a non-resonant antenna to system resonance and better the losses in the coax feeding a resonant antenna. How to do that is described on my web page. -- 73, Cecil http://www.qsl.net/w5dxp |
Back to TX distance - you really need to get a good book on propagation and
understand the solar cycle and the characteristics of each band. For example -- on 10M with the right time in the 11 year solar cycle -- a minimum antenna and a few watts will work the world (at the right time of day) On 160M in the day time in the summer with low power -- you ain't going anywhere -- The Anon Keyboard I doubt, therefore I might be "Cecil Moore" wrote in message ... Bill Turner wrote: Once the antenna is resonant, a simple L-C network will transform the impedance to 50 ohms resistive and you are all set. Simple, cheap and reliable, all the things a tuner is not. And single-banded, one thing a tuner is not. :-) The antenna need not be resonant. Under certain easily obtainable conditions, the length of the open-wire transmission line can tune a non-resonant antenna to system resonance and better the losses in the coax feeding a resonant antenna. How to do that is described on my web page. -- 73, Cecil http://www.qsl.net/w5dxp |
On Sun, 28 Nov 2004 12:06:48 -0800, Bill Turner
wrote: On Sun, 28 Nov 2004 15:17:53 GMT, 'Doc wrote: Since the backstay (or frontstay) is ~there~ anyway, why not use it? Certainly not the 'best' thing in the world (whatever that is), but 'better' than most alternative$. There are insulators designed just for backstays which one could place at the 16.4 foot level for 20 meters, or multiple locations for multiple bands. In a home situation, I wouldn't care much but on a small boat on the open sea, KISS could save your life, IMO. Some people have a 'phobia' about tuners. If you don't want to use one, that's fine. The word "phobia" means a fear of. I'm certainly not afraid of tuners, but I believe making the antenna right is better than using a device to compensate for one that isn't. "Bias" would be a better word. Once the antenna is resonant, a simple L-C network will transform the impedance to 50 ohms resistive and you are all set. Simple, cheap and reliable, all the things a tuner is not. They do make 'things' much easier and the difference in performance is 'acceptible' in most cases (acceptible being relative). Sigh. It's kind of difficult to get a resonant quarter wave into a back stay as you don't usually know where ground is. Ground can be any number of feet from where the feed point is on a boat. Every thing above real ground is antenna. 73 Gary K4FMX |
On Sun, 28 Nov 2004 12:06:48 -0800, Bill Turner
wrote: On Sun, 28 Nov 2004 15:17:53 GMT, 'Doc wrote: Since the backstay (or frontstay) is ~there~ anyway, why not use it? Certainly not the 'best' thing in the world (whatever that is), but 'better' than most alternative$. There are insulators designed just for backstays which one could place at the 16.4 foot level for 20 meters, or multiple locations for multiple bands. In a home situation, I wouldn't care much but on a small boat on the open sea, KISS could save your life, IMO. Some people have a 'phobia' about tuners. If you don't want to use one, that's fine. The word "phobia" means a fear of. I'm certainly not afraid of tuners, but I believe making the antenna right is better than using a device to compensate for one that isn't. "Bias" would be a better word. Once the antenna is resonant, a simple L-C network will transform the impedance to 50 ohms resistive and you are all set. Simple, cheap and reliable, all the things a tuner is not. They do make 'things' much easier and the difference in performance is 'acceptible' in most cases (acceptible being relative). Sigh. It's kind of difficult to get a resonant quarter wave into a back stay as you don't usually know where ground is. Ground can be any number of feet from where the feed point is on a boat. Every thing above real ground is antenna. 73 Gary K4FMX |
Bill Turner wrote:
A simple pigtail with a banana plug would make the L-network as multi banded as you have L-networks. Still simple, cheap and reliable. Let's see, would I rather switch knife switches at my operating position or go outside in a Texas Thunder Storm to attach the pigtails? At my age, I could develop pneumonia or catch the flu (no flu shot this year). Pneumonia and/or flu is not simple or cheap. Think I'll stick with my Ladder-Line Length Selector. :-) Moral: Use virtually lossless transmission line and do all the matching in the comfort of the shack. -- 73, Cecil http://www.qsl.net/w5dxp |
Bill Turner wrote:
A simple pigtail with a banana plug would make the L-network as multi banded as you have L-networks. Still simple, cheap and reliable. Let's see, would I rather switch knife switches at my operating position or go outside in a Texas Thunder Storm to attach the pigtails? At my age, I could develop pneumonia or catch the flu (no flu shot this year). Pneumonia and/or flu is not simple or cheap. Think I'll stick with my Ladder-Line Length Selector. :-) Moral: Use virtually lossless transmission line and do all the matching in the comfort of the shack. -- 73, Cecil http://www.qsl.net/w5dxp |
Bill I agree But
The original poster sed: "My very first contacts were established with 2 land stations on 14300 at 100W that were about 1000 miles away. They both reported that my signal was good and that it sounded like I was "sitting right next to them". I have no idea if this was a good distance, great, or mediocre." So I assume he was after contacts of several hundred (thousand) miles - not ground wave. My point was this for the 160M band (From a book on propagation) "160 meters. Daytime conditions for this band suffer from extreme D-layer absorption, reducing the amount of signal to levels far below the noise floor of our receivers. This limits daytime coverage to essentially ground-wave coverage. At night, the D layer dissipates rapidly and worldwide 160-meter communication becomes possible via the F2-layer and in ducts in the electron density valley above the E region peak. Depending on the propagation mode, high or low elevation angles may be required. A limiting factor is the noise levels prevalent at these frequencies, both atmospheric and man-made as well as tropical and mid-latitude thunderstorms which cause high levels of static in the summer season. Winter conditions are much better, making winter evenings the best time to work 160-meter DX. So you might have ground wave on 160M during the day to 100 miles or so. See URL for details and formulas on ground wave distances http://www.qsl.net/g3cwi/Downloads/Propagation%201.doc As I sed --- way too much on propagation to put on a post and cover all the variables and details -- the original poster needs to get a good book or at least look at this free URL http://www.ae4rv.com/tn/propflash.htm And of course -- "on 10 meters at the bottom of the sunspot cycle 10 is open nearly every day to somewhere." Sure -- ground wave and perhaps sporadic-E -- The Anon Keyboard I doubt, therefore I might be "Bill Turner" wrote in message ... On Sun, 28 Nov 2004 13:01:47 -0800, "Keyboard In The Wilderness" wrote: On 160M in the day time in the summer with low power -- you ain't going anywhere __________________________________________________ _______ This is true but not for the reason you might think. 160 meters has excellent groundwave propagation; better than any other amateur band in fact, but the lack of stations is the real reason 160 is mostly dead in the daytime. It's a self fulfilling prophecy - nobody is on, so I'm not going to get on either. The same thing happens on 10 meters at the bottom of the sunspot cycle even though 10 is open nearly every day to somewhere. -- Bill W6WRT |
Bill I agree But
The original poster sed: "My very first contacts were established with 2 land stations on 14300 at 100W that were about 1000 miles away. They both reported that my signal was good and that it sounded like I was "sitting right next to them". I have no idea if this was a good distance, great, or mediocre." So I assume he was after contacts of several hundred (thousand) miles - not ground wave. My point was this for the 160M band (From a book on propagation) "160 meters. Daytime conditions for this band suffer from extreme D-layer absorption, reducing the amount of signal to levels far below the noise floor of our receivers. This limits daytime coverage to essentially ground-wave coverage. At night, the D layer dissipates rapidly and worldwide 160-meter communication becomes possible via the F2-layer and in ducts in the electron density valley above the E region peak. Depending on the propagation mode, high or low elevation angles may be required. A limiting factor is the noise levels prevalent at these frequencies, both atmospheric and man-made as well as tropical and mid-latitude thunderstorms which cause high levels of static in the summer season. Winter conditions are much better, making winter evenings the best time to work 160-meter DX. So you might have ground wave on 160M during the day to 100 miles or so. See URL for details and formulas on ground wave distances http://www.qsl.net/g3cwi/Downloads/Propagation%201.doc As I sed --- way too much on propagation to put on a post and cover all the variables and details -- the original poster needs to get a good book or at least look at this free URL http://www.ae4rv.com/tn/propflash.htm And of course -- "on 10 meters at the bottom of the sunspot cycle 10 is open nearly every day to somewhere." Sure -- ground wave and perhaps sporadic-E -- The Anon Keyboard I doubt, therefore I might be "Bill Turner" wrote in message ... On Sun, 28 Nov 2004 13:01:47 -0800, "Keyboard In The Wilderness" wrote: On 160M in the day time in the summer with low power -- you ain't going anywhere __________________________________________________ _______ This is true but not for the reason you might think. 160 meters has excellent groundwave propagation; better than any other amateur band in fact, but the lack of stations is the real reason 160 is mostly dead in the daytime. It's a self fulfilling prophecy - nobody is on, so I'm not going to get on either. The same thing happens on 10 meters at the bottom of the sunspot cycle even though 10 is open nearly every day to somewhere. -- Bill W6WRT |
OOppps you are right -- I shouldn't have sed anywhere.
Of course ground wave may get out to 100 miles. See my other post -- The Anon Keyboard I doubt, therefore I might be "Bill Turner" wrote in message ... On Sun, 28 Nov 2004 13:01:47 -0800, "Keyboard In The Wilderness" wrote: On 160M in the day time in the summer with low power -- you ain't going anywhere __________________________________________________ _______ This is true but not for the reason you might think. 160 meters has excellent groundwave propagation; better than any other amateur band in fact, but the lack of stations is the real reason 160 is mostly dead in the daytime. It's a self fulfilling prophecy - nobody is on, so I'm not going to get on either. The same thing happens on 10 meters at the bottom of the sunspot cycle even though 10 is open nearly every day to somewhere. -- Bill W6WRT |
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