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Can i work 7~28 MHz with a 10 mt dipole?
I can install only a dipole of about 10 meters
(as inverted V). Is there any project, any commercial antenna of such length, that allow me to work all band 7 - 14 - 21 - 28 MHz ? Thanks |
"/* frank */" wrote in message ... I can install only a dipole of about 10 meters (as inverted V). sure, go for it! Is there any project, any commercial antenna of such length, that allow me to work all band 7 - 14 - 21 - 28 MHz ? just put one up, add a tuner if your radio doesn't have one, and get on the air! it will work fine, cover all bands from dc to daylight, is cheap, easy to use, whitens your teeth while you transmit, and is non-fattening. don't go pay anyone for it, just grab some wire and (horrors upon horrors) build it yourself. oh, and ignore the inevitable discussion that will follow shortly about why you have to use open wire feeders instead of coax, endless debate about swr, tuning, reflections, losses, matching, etc, etc, etc... stop reading now and go get on the air! |
"/* frank */" wrote in message ... I can install only a dipole of about 10 meters (as inverted V). sure, go for it! Is there any project, any commercial antenna of such length, that allow me to work all band 7 - 14 - 21 - 28 MHz ? just put one up, add a tuner if your radio doesn't have one, and get on the air! it will work fine, cover all bands from dc to daylight, is cheap, easy to use, whitens your teeth while you transmit, and is non-fattening. don't go pay anyone for it, just grab some wire and (horrors upon horrors) build it yourself. oh, and ignore the inevitable discussion that will follow shortly about why you have to use open wire feeders instead of coax, endless debate about swr, tuning, reflections, losses, matching, etc, etc, etc... stop reading now and go get on the air! |
"/* frank */" wrote in message ... I can install only a dipole of about 10 meters (as inverted V). Is there any project, any commercial antenna of such length, that allow me to work all band 7 - 14 - 21 - 28 MHz ? A very good antenna is a half-sized G5RV (7.5m each side). Excellent results 7 - 28 MHz. Use tuned feeders (any length) and ATU. 73, Peter |
"/* frank */" wrote in message ... I can install only a dipole of about 10 meters (as inverted V). Is there any project, any commercial antenna of such length, that allow me to work all band 7 - 14 - 21 - 28 MHz ? A very good antenna is a half-sized G5RV (7.5m each side). Excellent results 7 - 28 MHz. Use tuned feeders (any length) and ATU. 73, Peter |
On Fri, 02 Jul 2004 07:42:24 +0200, /* frank */
wrote: I can install only a dipole of about 10 meters (as inverted V). Is there any project, any commercial antenna of such length, that allow me to work all band 7 - 14 - 21 - 28 MHz ? Thanks If you can make it 11 meters long, about 33 feet, that should get you 14 thru 28 mhz, with the use of 450 ohm feedline and a manual tuner. If you can stretch it to 51 feet, you can add 10 and 7 mhz. bob k5qwg |
On Fri, 02 Jul 2004 07:42:24 +0200, /* frank */
wrote: I can install only a dipole of about 10 meters (as inverted V). Is there any project, any commercial antenna of such length, that allow me to work all band 7 - 14 - 21 - 28 MHz ? Thanks If you can make it 11 meters long, about 33 feet, that should get you 14 thru 28 mhz, with the use of 450 ohm feedline and a manual tuner. If you can stretch it to 51 feet, you can add 10 and 7 mhz. bob k5qwg |
"Bob Miller" wrote in message ... On Fri, 02 Jul 2004 07:42:24 +0200, /* frank */ wrote: I can install only a dipole of about 10 meters (as inverted V). Is there any project, any commercial antenna of such length, that allow me to work all band 7 - 14 - 21 - 28 MHz ? Thanks If you can make it 11 meters long, about 33 feet, that should get you 14 thru 28 mhz, with the use of 450 ohm feedline and a manual tuner. If you can stretch it to 51 feet, you can add 10 and 7 mhz. bob k5qwg 10 meters = 32.8 feet 11 meters = 36.1 feet A meter is approximately 3 feet and 3 inches NOT just 3 feet. Those inches add up after a while. Dee D. Flint, N8UZE |
"Bob Miller" wrote in message ... On Fri, 02 Jul 2004 07:42:24 +0200, /* frank */ wrote: I can install only a dipole of about 10 meters (as inverted V). Is there any project, any commercial antenna of such length, that allow me to work all band 7 - 14 - 21 - 28 MHz ? Thanks If you can make it 11 meters long, about 33 feet, that should get you 14 thru 28 mhz, with the use of 450 ohm feedline and a manual tuner. If you can stretch it to 51 feet, you can add 10 and 7 mhz. bob k5qwg 10 meters = 32.8 feet 11 meters = 36.1 feet A meter is approximately 3 feet and 3 inches NOT just 3 feet. Those inches add up after a while. Dee D. Flint, N8UZE |
Franj,
Can it be done? Yes. Will it be the 'best' of antennas on all those bands? No. But, if that's all that you can do, then do it. Anything is 'better' than nothing! Beware of antenna manufacturor's claims. Taxes are never going down, and there's no 'miracle' antennas that do everything... 'Doc |
Franj,
Can it be done? Yes. Will it be the 'best' of antennas on all those bands? No. But, if that's all that you can do, then do it. Anything is 'better' than nothing! Beware of antenna manufacturor's claims. Taxes are never going down, and there's no 'miracle' antennas that do everything... 'Doc |
don't worry about it... cut it any length you can and use a tuner... it will
work all bands from 160m to 6m and probably higher. don't count inches, GET ON THE AIR and have fun! "Dee D. Flint" wrote in message ... "Bob Miller" wrote in message ... On Fri, 02 Jul 2004 07:42:24 +0200, /* frank */ wrote: I can install only a dipole of about 10 meters (as inverted V). Is there any project, any commercial antenna of such length, that allow me to work all band 7 - 14 - 21 - 28 MHz ? Thanks If you can make it 11 meters long, about 33 feet, that should get you 14 thru 28 mhz, with the use of 450 ohm feedline and a manual tuner. If you can stretch it to 51 feet, you can add 10 and 7 mhz. bob k5qwg 10 meters = 32.8 feet 11 meters = 36.1 feet A meter is approximately 3 feet and 3 inches NOT just 3 feet. Those inches add up after a while. Dee D. Flint, N8UZE |
don't worry about it... cut it any length you can and use a tuner... it will
work all bands from 160m to 6m and probably higher. don't count inches, GET ON THE AIR and have fun! "Dee D. Flint" wrote in message ... "Bob Miller" wrote in message ... On Fri, 02 Jul 2004 07:42:24 +0200, /* frank */ wrote: I can install only a dipole of about 10 meters (as inverted V). Is there any project, any commercial antenna of such length, that allow me to work all band 7 - 14 - 21 - 28 MHz ? Thanks If you can make it 11 meters long, about 33 feet, that should get you 14 thru 28 mhz, with the use of 450 ohm feedline and a manual tuner. If you can stretch it to 51 feet, you can add 10 and 7 mhz. bob k5qwg 10 meters = 32.8 feet 11 meters = 36.1 feet A meter is approximately 3 feet and 3 inches NOT just 3 feet. Those inches add up after a while. Dee D. Flint, N8UZE |
Is there any project, any commercial antenna of such length, that allow me to work all band 7 - 14 - 21 - 28 MHz ? =========================== All dipoles of any reasonable length, inverted-V or not, commercial or home brew, are quite efficient on all HF bands in that they all radiate most of the power which is put into them. The problems lie in loss in the transmission line and the essential tuner. Erect the highest and longest dipole you can, feed it with open-wire line, use a tuner appropriate for each band of interest and you won't be disappointed. Or better still, if you can manage it, erect the longest inverted-L you can and feed it at one end tuned against a modest ground system such as a dozen bent surface or shallow-buried radials. ---- Reg, G4FGQ |
Is there any project, any commercial antenna of such length, that allow me to work all band 7 - 14 - 21 - 28 MHz ? =========================== All dipoles of any reasonable length, inverted-V or not, commercial or home brew, are quite efficient on all HF bands in that they all radiate most of the power which is put into them. The problems lie in loss in the transmission line and the essential tuner. Erect the highest and longest dipole you can, feed it with open-wire line, use a tuner appropriate for each band of interest and you won't be disappointed. Or better still, if you can manage it, erect the longest inverted-L you can and feed it at one end tuned against a modest ground system such as a dozen bent surface or shallow-buried radials. ---- Reg, G4FGQ |
Bob Miller ha scritto:
with the use of 450 ohm feedline and a manual tuner. Where I can purchase this kind of line ? (some online mall that delivery outside USA/Canada), because I can't find it here in Italy. Thanks again Best 73 |
Bob Miller ha scritto:
with the use of 450 ohm feedline and a manual tuner. Where I can purchase this kind of line ? (some online mall that delivery outside USA/Canada), because I can't find it here in Italy. Thanks again Best 73 |
"Dave" wrote in message ... don't worry about it... cut it any length you can and use a tuner... it will work all bands from 160m to 6m and probably higher. don't count inches, GET ON THE AIR and have fun! I agree that he should just get on the air. But those inaccurate conversions although only inches result in feet in antenna dimensions and is not insignificant. If one wants to get into resonant antennas, it becomes particularly important. Even at 10 meters, the difference is 2.5 feet for a full wave length antenna between using a conversion of 3 feet per meter versus 3.25 feet (3 feet 3 inches) per meter. For a half wave dipole it would be 1.25 feet. At 160 meters the difference climbs to 40 feet for a full wave loop and 20 feet for a dipole. These differences can be important even with a tuner. We've got an 80 meter loop cut for the voice segment. My internal tuner will NOT tune it for the CW portion so I must use my external tuner. If we had based the length on using 3ft/meter rather than the 3.25ft/meter, it would have been too short to tune on even the voice portion of the band. Dee D. Flint, N8UZE "Dee D. Flint" wrote in message ... "Bob Miller" wrote in message ... On Fri, 02 Jul 2004 07:42:24 +0200, /* frank */ wrote: I can install only a dipole of about 10 meters (as inverted V). Is there any project, any commercial antenna of such length, that allow me to work all band 7 - 14 - 21 - 28 MHz ? Thanks If you can make it 11 meters long, about 33 feet, that should get you 14 thru 28 mhz, with the use of 450 ohm feedline and a manual tuner. If you can stretch it to 51 feet, you can add 10 and 7 mhz. bob k5qwg 10 meters = 32.8 feet 11 meters = 36.1 feet A meter is approximately 3 feet and 3 inches NOT just 3 feet. Those inches add up after a while. Dee D. Flint, N8UZE |
"Dave" wrote in message ... don't worry about it... cut it any length you can and use a tuner... it will work all bands from 160m to 6m and probably higher. don't count inches, GET ON THE AIR and have fun! I agree that he should just get on the air. But those inaccurate conversions although only inches result in feet in antenna dimensions and is not insignificant. If one wants to get into resonant antennas, it becomes particularly important. Even at 10 meters, the difference is 2.5 feet for a full wave length antenna between using a conversion of 3 feet per meter versus 3.25 feet (3 feet 3 inches) per meter. For a half wave dipole it would be 1.25 feet. At 160 meters the difference climbs to 40 feet for a full wave loop and 20 feet for a dipole. These differences can be important even with a tuner. We've got an 80 meter loop cut for the voice segment. My internal tuner will NOT tune it for the CW portion so I must use my external tuner. If we had based the length on using 3ft/meter rather than the 3.25ft/meter, it would have been too short to tune on even the voice portion of the band. Dee D. Flint, N8UZE "Dee D. Flint" wrote in message ... "Bob Miller" wrote in message ... On Fri, 02 Jul 2004 07:42:24 +0200, /* frank */ wrote: I can install only a dipole of about 10 meters (as inverted V). Is there any project, any commercial antenna of such length, that allow me to work all band 7 - 14 - 21 - 28 MHz ? Thanks If you can make it 11 meters long, about 33 feet, that should get you 14 thru 28 mhz, with the use of 450 ohm feedline and a manual tuner. If you can stretch it to 51 feet, you can add 10 and 7 mhz. bob k5qwg 10 meters = 32.8 feet 11 meters = 36.1 feet A meter is approximately 3 feet and 3 inches NOT just 3 feet. Those inches add up after a while. Dee D. Flint, N8UZE |
with the use of 450 ohm feedline and a manual tuner.
Where I can purchase this kind of line ? (some online mall that delivery outside USA/Canada), because I can't find it here in Italy. =============================== Frank, the exact impedance of the high impedance line doesn't matter at all. You don't even need to know what its impedance is. Line loss is small just because it has a high impedance. Any line where the pair of wires are spaced apart more than 25mm will be satisfactory. Wire spacing can change along its length without any bad effects. The only effect will be a change in tuner component settings. If you are unable to purchase a line then it is not difficult to make. You can make the stuff in less time than it takes to order and deliver from a manufacturer. Use 1.6 or 1.3 mm diameter wire. Space the wires 50 mm to 100 mm apart. There are many ways of fixing the wire to the ends of rigid plastic spacers. The distance between spacers along the line can be anything from 100 to 200 mm. Construction depends on your judgement of what weather conditions, wind velocity, etc., the line will have to withstand and the time in months. Failure due to flexing in the wind can be a problem. ---- Reg, G4FGQ |
with the use of 450 ohm feedline and a manual tuner.
Where I can purchase this kind of line ? (some online mall that delivery outside USA/Canada), because I can't find it here in Italy. =============================== Frank, the exact impedance of the high impedance line doesn't matter at all. You don't even need to know what its impedance is. Line loss is small just because it has a high impedance. Any line where the pair of wires are spaced apart more than 25mm will be satisfactory. Wire spacing can change along its length without any bad effects. The only effect will be a change in tuner component settings. If you are unable to purchase a line then it is not difficult to make. You can make the stuff in less time than it takes to order and deliver from a manufacturer. Use 1.6 or 1.3 mm diameter wire. Space the wires 50 mm to 100 mm apart. There are many ways of fixing the wire to the ends of rigid plastic spacers. The distance between spacers along the line can be anything from 100 to 200 mm. Construction depends on your judgement of what weather conditions, wind velocity, etc., the line will have to withstand and the time in months. Failure due to flexing in the wind can be a problem. ---- Reg, G4FGQ |
"/* frank */" wrote in message ... I can install only a dipole of about 10 meters (as inverted V). Is there any project, any commercial antenna of such length, that allow me to work all band 7 - 14 - 21 - 28 MHz ? Thanks Frank, Any antenna you put up is not forever. So, start small. At this pont in the sunspot cycle there is not much propagation on 10 & 15 m. A wire 10 m long is resonant at very close to 14.2 MHz. Feed it in the center with 50 Ohm coax, and get on 20 meters. As an inverted V, you should be able to trim the SWR to well below 1.5:1. Tam/WB2TT |
"/* frank */" wrote in message ... I can install only a dipole of about 10 meters (as inverted V). Is there any project, any commercial antenna of such length, that allow me to work all band 7 - 14 - 21 - 28 MHz ? Thanks Frank, Any antenna you put up is not forever. So, start small. At this pont in the sunspot cycle there is not much propagation on 10 & 15 m. A wire 10 m long is resonant at very close to 14.2 MHz. Feed it in the center with 50 Ohm coax, and get on 20 meters. As an inverted V, you should be able to trim the SWR to well below 1.5:1. Tam/WB2TT |
On Fri, 2 Jul 2004 08:59:17 -0400, "Dee D. Flint"
wrote: "Bob Miller" wrote in message .. . On Fri, 02 Jul 2004 07:42:24 +0200, /* frank */ wrote: I can install only a dipole of about 10 meters (as inverted V). Is there any project, any commercial antenna of such length, that allow me to work all band 7 - 14 - 21 - 28 MHz ? Thanks If you can make it 11 meters long, about 33 feet, that should get you 14 thru 28 mhz, with the use of 450 ohm feedline and a manual tuner. If you can stretch it to 51 feet, you can add 10 and 7 mhz. bob k5qwg 10 meters = 32.8 feet 11 meters = 36.1 feet A meter is approximately 3 feet and 3 inches NOT just 3 feet. Those inches add up after a while. Dee D. Flint, N8UZE Yes, this is how I bombed in basic Trigonometry and decided to not become an an Electrical Engineer :-) Bob k5qwg |
On Fri, 2 Jul 2004 08:59:17 -0400, "Dee D. Flint"
wrote: "Bob Miller" wrote in message .. . On Fri, 02 Jul 2004 07:42:24 +0200, /* frank */ wrote: I can install only a dipole of about 10 meters (as inverted V). Is there any project, any commercial antenna of such length, that allow me to work all band 7 - 14 - 21 - 28 MHz ? Thanks If you can make it 11 meters long, about 33 feet, that should get you 14 thru 28 mhz, with the use of 450 ohm feedline and a manual tuner. If you can stretch it to 51 feet, you can add 10 and 7 mhz. bob k5qwg 10 meters = 32.8 feet 11 meters = 36.1 feet A meter is approximately 3 feet and 3 inches NOT just 3 feet. Those inches add up after a while. Dee D. Flint, N8UZE Yes, this is how I bombed in basic Trigonometry and decided to not become an an Electrical Engineer :-) Bob k5qwg |
"Bob Miller" wrote in message ... On Fri, 2 Jul 2004 08:59:17 -0400, "Dee D. Flint" wrote: "Bob Miller" wrote in message .. . On Fri, 02 Jul 2004 07:42:24 +0200, /* frank */ wrote: I can install only a dipole of about 10 meters (as inverted V). Is there any project, any commercial antenna of such length, that allow me to work all band 7 - 14 - 21 - 28 MHz ? Thanks If you can make it 11 meters long, about 33 feet, that should get you 14 thru 28 mhz, with the use of 450 ohm feedline and a manual tuner. If you can stretch it to 51 feet, you can add 10 and 7 mhz. bob k5qwg 10 meters = 32.8 feet 11 meters = 36.1 feet A meter is approximately 3 feet and 3 inches NOT just 3 feet. Those inches add up after a while. Dee D. Flint, N8UZE Yes, this is how I bombed in basic Trigonometry and decided to not become an an Electrical Engineer :-) Bob k5qwg I tend to remember that a meter is 39.37 inches. Makes for an extra step, but fewer numbers to remember. Tam/WB2TT |
"Bob Miller" wrote in message ... On Fri, 2 Jul 2004 08:59:17 -0400, "Dee D. Flint" wrote: "Bob Miller" wrote in message .. . On Fri, 02 Jul 2004 07:42:24 +0200, /* frank */ wrote: I can install only a dipole of about 10 meters (as inverted V). Is there any project, any commercial antenna of such length, that allow me to work all band 7 - 14 - 21 - 28 MHz ? Thanks If you can make it 11 meters long, about 33 feet, that should get you 14 thru 28 mhz, with the use of 450 ohm feedline and a manual tuner. If you can stretch it to 51 feet, you can add 10 and 7 mhz. bob k5qwg 10 meters = 32.8 feet 11 meters = 36.1 feet A meter is approximately 3 feet and 3 inches NOT just 3 feet. Those inches add up after a while. Dee D. Flint, N8UZE Yes, this is how I bombed in basic Trigonometry and decided to not become an an Electrical Engineer :-) Bob k5qwg I tend to remember that a meter is 39.37 inches. Makes for an extra step, but fewer numbers to remember. Tam/WB2TT |
Dear Tam:
During WW2 the value was changed. UK, Canada, and USA each had a slightly different value. Became a problem with things having threads. I think that the Canadian value won. Now: one inch is 25.4 mm exactly. 73 Mac N8TT -- J. Mc Laughlin - Michigan USA Home: "Tam/WB2TT" wrote in message ... snip 10 meters = 32.8 feet 11 meters = 36.1 feet A meter is approximately 3 feet and 3 inches NOT just 3 feet. Those inches add up after a while. Dee D. Flint, N8UZE Yes, this is how I bombed in basic Trigonometry and decided to not become an an Electrical Engineer :-) Bob k5qwg I tend to remember that a meter is 39.37 inches. Makes for an extra step, but fewer numbers to remember. Tam/WB2TT |
Dear Tam:
During WW2 the value was changed. UK, Canada, and USA each had a slightly different value. Became a problem with things having threads. I think that the Canadian value won. Now: one inch is 25.4 mm exactly. 73 Mac N8TT -- J. Mc Laughlin - Michigan USA Home: "Tam/WB2TT" wrote in message ... snip 10 meters = 32.8 feet 11 meters = 36.1 feet A meter is approximately 3 feet and 3 inches NOT just 3 feet. Those inches add up after a while. Dee D. Flint, N8UZE Yes, this is how I bombed in basic Trigonometry and decided to not become an an Electrical Engineer :-) Bob k5qwg I tend to remember that a meter is 39.37 inches. Makes for an extra step, but fewer numbers to remember. Tam/WB2TT |
"/* frank */" wrote in message ... I can install only a dipole of about 10 meters (as inverted V). Is there any project, any commercial antenna of such length, that allow me to work all band 7 - 14 - 21 - 28 MHz ? Thanks It's probably going to work like crap on 7 MHz. Consider buying a GOOD tuner, and also try tricks like feeding the coax common mode (shield and center tied together) to run your ten meter dipole as a top loaded vertical wire. This assumes you can run the coax or balanced line in a straight run away from existing structures. You'll also need a good ground or a few on the ground radials for the antenna to work against when it is being run as a vertical. Don't be afraid to experiment. Pete |
"/* frank */" wrote in message ... I can install only a dipole of about 10 meters (as inverted V). Is there any project, any commercial antenna of such length, that allow me to work all band 7 - 14 - 21 - 28 MHz ? Thanks It's probably going to work like crap on 7 MHz. Consider buying a GOOD tuner, and also try tricks like feeding the coax common mode (shield and center tied together) to run your ten meter dipole as a top loaded vertical wire. This assumes you can run the coax or balanced line in a straight run away from existing structures. You'll also need a good ground or a few on the ground radials for the antenna to work against when it is being run as a vertical. Don't be afraid to experiment. Pete |
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