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#1
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The Lazy H does not seem to exhibit any gain over a dipole in thereal world
Well I've worked with the center fed Lazy H antenna design on 10 meters for several few weeks now. I tried 1/2 wave spacing between the top and bottom elements, 5/8th wave spacing between the top and bottom elements, I put it up at 40 feet and 50 feet at the top wire, I tried different lengths of 450 ohm feed-line, and this antenna consistently under performs a 1/2 wave dipole cut for the same frequency. A simple 1/2 wave dipole consistently out performs the center fed version of Lazy H antenna even when the Lazy H is given a 20 foot height advantage over the lowly dipole. I even put up the Lazy H in two completely different locations over 180 miles apart. I also tried two completely different antenna tuners (Dentron MT-3000a and Drake MN-75 with the 4:1 balun installed). Out of over 200 A/B test the Lazy H antenna only out performed the dipole on one test with a station in Texas just before the propagation faded out for the day, The next day when the propagation was back I heard the same station on the same frequency and the dipole out performed the Lazy H for the rest of the day. I'm not sure what special propagation mode is required for the Lazy H to have some gain through some pin hole direction, but the version of the Lazy H center fed with 450 ohm ladder line back to the antenna tuner is a complete failure. I even re-built the antenna from scratch using a different piece 450 ladder line for the inter connecting piece. I also verified the length of each 1/2 wave section with a tape measure. I verified with an ohm meter that the top left element was connected to the bottom left element and the right top element was connected to the bottom right element. I verified there was no unexpected connectivity between the left and right elements, and I verified both sides of the ladder line were connected back to the antenna tuner. I made sure there was no twist in the ladder line connecting the top and bottom elements. I would like to petition the ARRL to remove the center fed Lazy H from the antenna handbook as it clearly does not work as specified. A lowly mono band dipole on the same design frequency will consistently out perform the center feed Lazy H even when the Lazy H is given a 20 foot height advantage on10 meters. Before any of you reply with charts and graphs from EZNEC software, turn off your computer, go out in the back yard, and actually build a center fed Lazy H antenna with 450 ladder line all the way back to the antenna tuner. Then do real world A/B comparisons with a plain old mono band dipole cut for the same frequency, and you will find I am telling the truth. The center fed Lazy H does not have any gain over a 1/2 wave dipole broadside to the antenna. None. Here is what you will fine if you actually build the center fed Lazy H and compare it to a 1/2 wave mono band dipole cut for the same same frequency; 1) Your tuner will have to use extreme setting to match the Lazy H. 2) In some instances the tuner will not be able to match the Lazy H depending on the length of the ladder line feeding the antenna. You may have to increase or decrease the length of the ladder line feeding the Lazy H to get your antenna tuner to match it. 3) A 1/2 wave dipole will beat the Lazy H 99.99 percent of the time in it's favored direction even if the Lazy H is given a 20 foot height advantage over the dipole. 4) An extended double zepp with a 450 ohm matching section back to a 1:1 balun and then to 50 ohm coax cut for the same frequency and hung from the same ropes previously used to support the Lazy H will blow the Lazy H in the dirt. In a nutshell, this antenna sucks! Michael Rawls KS4HY |
#2
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The Lazy H does not seem to exhibit any gain over a dipole in the real world
Michael Inscribed thus:
Well I've worked with the center fed Lazy H antenna design on 10 meters for several few weeks now. I tried 1/2 wave spacing between the top and bottom elements, 5/8th wave spacing between the top and bottom elements, I put it up at 40 feet and 50 feet at the top wire, I tried different lengths of 450 ohm feed-line, and this antenna consistently under performs a 1/2 wave dipole cut for the same frequency. A simple 1/2 wave dipole consistently out performs the center fed version of Lazy H antenna even when the Lazy H is given a 20 foot height advantage over the lowly dipole. I even put up the Lazy H in two completely different locations over 180 miles apart. I also tried two completely different antenna tuners (Dentron MT-3000a and Drake MN-75 with the 4:1 balun installed). Out of over 200 A/B test the Lazy H antenna only out performed the dipole on one test with a station in Texas just before the propagation faded out for the day, The next day when the propagation was back I heard the same station on the same frequency and the dipole out performed the Lazy H for the rest of the day. I'm not sure what special propagation mode is required for the Lazy H to have some gain through some pin hole direction, but the version of the Lazy H center fed with 450 ohm ladder line back to the antenna tuner is a complete failure. I even re-built the antenna from scratch using a different piece 450 ladder line for the inter connecting piece. I also verified the length of each 1/2 wave section with a tape measure. I verified with an ohm meter that the top left element was connected to the bottom left element and the right top element was connected to the bottom right element. I verified there was no unexpected connectivity between the left and right elements, and I verified both sides of the ladder line were connected back to the antenna tuner. I made sure there was no twist in the ladder line connecting the top and bottom elements. I would like to petition the ARRL to remove the center fed Lazy H from the antenna handbook as it clearly does not work as specified. A lowly mono band dipole on the same design frequency will consistently out perform the center feed Lazy H even when the Lazy H is given a 20 foot height advantage on10 meters. Before any of you reply with charts and graphs from EZNEC software, turn off your computer, go out in the back yard, and actually build a center fed Lazy H antenna with 450 ladder line all the way back to the antenna tuner. Then do real world A/B comparisons with a plain old mono band dipole cut for the same frequency, and you will find I am telling the truth. The center fed Lazy H does not have any gain over a 1/2 wave dipole broadside to the antenna. None. Here is what you will fine if you actually build the center fed Lazy H and compare it to a 1/2 wave mono band dipole cut for the same same frequency; 1) Your tuner will have to use extreme setting to match the Lazy H. 2) In some instances the tuner will not be able to match the Lazy H depending on the length of the ladder line feeding the antenna. You may have to increase or decrease the length of the ladder line feeding the Lazy H to get your antenna tuner to match it. 3) A 1/2 wave dipole will beat the Lazy H 99.99 percent of the time in it's favored direction even if the Lazy H is given a 20 foot height advantage over the dipole. 4) An extended double zepp with a 450 ohm matching section back to a 1:1 balun and then to 50 ohm coax cut for the same frequency and hung from the same ropes previously used to support the Lazy H will blow the Lazy H in the dirt. In a nutshell, this antenna sucks! Michael Rawls KS4HY Tried mounting it horizontally ? -- Best Regards: Baron. |
#3
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The Lazy H does not seem to exhibit any gain over a dipole in thereal world
On May 30, 2:44*pm, Baron wrote:
Michael Inscribed thus: * Well I've worked with the center fed Lazy H antenna design on 10 meters for several few weeks now. *I tried 1/2 wave spacing between the top and bottom elements, 5/8th wave spacing between the top and bottom elements, I put it up at 40 feet and 50 feet at the top wire, I tried different lengths of 450 ohm feed-line, and this antenna consistently under performs a 1/2 wave dipole cut for the same frequency. *A simple 1/2 wave dipole consistently out performs the center fed version of Lazy H antenna even when the Lazy H is given a 20 foot height advantage over the lowly dipole. I even put up the Lazy H in two completely different locations over 180 miles apart. I also tried two completely different antenna tuners (Dentron MT-3000a and Drake MN-75 with the 4:1 balun installed). Out of over 200 A/B test the Lazy H antenna only out performed the dipole on one test with a station in Texas just before the propagation faded out for the day, The next day when the propagation was back I heard the same station on the same frequency and the dipole out performed the Lazy H for the rest of the day. * I'm not sure what special propagation mode is required for the Lazy H to have some gain through some pin hole direction, but the version of the Lazy H center fed with 450 ohm ladder line back to the antenna tuner is a complete failure. *I even re-built the antenna from scratch using a different piece 450 ladder line for the inter connecting piece. I also verified the length of each 1/2 wave section with a tape measure. I verified with an ohm meter that the top left element was connected to the bottom left element and the right top element was connected to the bottom right element. *I verified there was no unexpected connectivity between the left and right elements, and I verified both sides of the ladder line were connected back to the antenna tuner. *I made sure there was no twist in the ladder line connecting the top and bottom elements. * I would like to petition the ARRL to remove the center fed Lazy H from the antenna handbook as it clearly does not work as specified. *A lowly mono band dipole on the same design frequency will consistently out perform the center feed Lazy H even when the Lazy H is given a 20 foot height advantage on10 meters. * Before any of you reply with charts and graphs from EZNEC software, turn off your computer, go out in the back yard, and actually build a center fed Lazy H antenna with 450 ladder line all the way back to the antenna tuner. *Then do real world A/B comparisons with a plain old mono band dipole cut for the same frequency, and you will find I am telling the truth. *The center fed Lazy H does not have any gain over a 1/2 wave dipole broadside to the antenna. None. Here is what you will fine if you actually build the center fed Lazy H and compare it to a 1/2 wave mono band dipole cut for the same same frequency; 1) Your tuner will have to use extreme setting to match the Lazy H. 2) In some instances the tuner will not be able to match the Lazy H depending on the length of the ladder line feeding the antenna. You may have to increase or decrease the length of the ladder line feeding the Lazy H to get your antenna tuner to match it. 3) A 1/2 wave dipole will beat the Lazy H 99.99 percent of the time in it's favored direction even if the Lazy H is given a 20 foot height advantage over the dipole. 4) An extended double zepp with a 450 ohm matching section back to a 1:1 balun and then to 50 ohm coax cut for the same frequency and hung from the same ropes previously used to support the Lazy H will blow the Lazy H in the dirt. In a nutshell, this antenna sucks! Michael Rawls KS4HY Tried mounting it horizontally ? -- Best Regards: * * * * * * * * * * * * * Baron. Hi Michael, I'm sorry to hear you think the lazy-H sucks. I used one on 20m years ago and it worked just fine--and no trouble in matching it with a tuner. However, I have a suggestion: Let's say you space the upper and lower radiating elements by 180°, which is 1/2wl. If you now use 450-ohm window line, the velocity factor for the line attaching the two elements together makes the electrical length of the line greater than 1/2wl, which means the phasing between the upper and lower elements is no longer correct, and therefore will not provide the expected gain. I'm not sure how much phasing error that will produce, but it's an issue you should consider. Correctly constructed, the lazy-H will definitely out perform a 1/2wl dipole, so if it doesn't for you there is sum ting definitely wong! If you feed at the center of the line connecting the two radiating elements the phasing will be correct regardless of the velocity factor, because the length from the center feed point on the connecting line will be the same from that point to each radiating element. With this configuration of feeding don't put a twist in the connecting line--the two radiating elements MUST be fed IN PHASE! If they're fed out of phase the array will look like an Adcock direction- finding antenna, with a deep null in the radiation pattern in the broadside direction. Just my thoughts, Walt, W2DU |
#4
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The Lazy H does not seem to exhibit any gain over a dipole in thereal world
Thanks for your input Walt, but I already thought of those things.
I definitely made the antenna correctly. According to the ARRL handbook when center feeding the Lazy H increasing the spacing beyond 1/2 wave makes the gain go up until the spacing reaches 5/8ths wave. The handbooks states 5.9 dbd gain for 1/2 wave spacing and 6.7 dbd for 5/8ths wave spacing. In the real world this antenna does not have any gain over a 1/2 wave dipole when center fed with 450 ohm ladder line all the way back to the tuner. The phasing was correct. On 14 MHz where it becomes two stacked dipoles the SWR comes down and the performance goes up, but on 28 MHz it consistently lags behind a dipole. I rebuilt this antenna twice. If you actually go to the trouble of making one for 10 meters, and compare it to a real world 28 Mhz 1/2 wave dipole, the Lazy H will fall far short of the predicted gain. I have been a ham since 1986. I wondered why I had heard so few hams using a Lazy H, and the one time I recalled hearing one the signal was weaker than the other hams using a dipole. I assumed at the time that I must have been off the side of the other ham's Lazy H, but after my real world test who knows. I'm going to remove the center feed from the antenna this week, and rework the Lazy H for end feed with a twist, a matching stub, and 1/2 wave spacing. Hopefully the end fed version of the Lazy H will live up to it's text book gain. I'd really like to have that 6 dbd gain along with the nulls off the sides, Michael Rawls KS4HY On May 30, 5:48*pm, walt wrote: On May 30, 2:44*pm, Baron wrote: Michael Inscribed thus: * Well I've worked with the center fed Lazy H antenna design on 10 meters for several few weeks now. *I tried 1/2 wave spacing between the top and bottom elements, 5/8th wave spacing between the top and bottom elements, I put it up at 40 feet and 50 feet at the top wire, I tried different lengths of 450 ohm feed-line, and this antenna consistently under performs a 1/2 wave dipole cut for the same frequency. *A simple 1/2 wave dipole consistently out performs the center fed version of Lazy H antenna even when the Lazy H is given a 20 foot height advantage over the lowly dipole. I even put up the Lazy H in two completely different locations over 180 miles apart. I also tried two completely different antenna tuners (Dentron MT-3000a and Drake MN-75 with the 4:1 balun installed). Out of over 200 A/B test the Lazy H antenna only out performed the dipole on one test with a station in Texas just before the propagation faded out for the day, The next day when the propagation was back I heard the same station on the same frequency and the dipole out performed the Lazy H for the rest of the day. * I'm not sure what special propagation mode is required for the Lazy H to have some gain through some pin hole direction, but the version of the Lazy H center fed with 450 ohm ladder line back to the antenna tuner is a complete failure. *I even re-built the antenna from scratch using a different piece 450 ladder line for the inter connecting piece. I also verified the length of each 1/2 wave section with a tape measure. I verified with an ohm meter that the top left element was connected to the bottom left element and the right top element was connected to the bottom right element. *I verified there was no unexpected connectivity between the left and right elements, and I verified both sides of the ladder line were connected back to the antenna tuner. *I made sure there was no twist in the ladder line connecting the top and bottom elements. * I would like to petition the ARRL to remove the center fed Lazy H from the antenna handbook as it clearly does not work as specified. *A lowly mono band dipole on the same design frequency will consistently out perform the center feed Lazy H even when the Lazy H is given a 20 foot height advantage on10 meters. * Before any of you reply with charts and graphs from EZNEC software, turn off your computer, go out in the back yard, and actually build a center fed Lazy H antenna with 450 ladder line all the way back to the antenna tuner. *Then do real world A/B comparisons with a plain old mono band dipole cut for the same frequency, and you will find I am telling the truth. *The center fed Lazy H does not have any gain over a 1/2 wave dipole broadside to the antenna. None. Here is what you will fine if you actually build the center fed Lazy H and compare it to a 1/2 wave mono band dipole cut for the same same frequency; 1) Your tuner will have to use extreme setting to match the Lazy H. 2) In some instances the tuner will not be able to match the Lazy H depending on the length of the ladder line feeding the antenna. You may have to increase or decrease the length of the ladder line feeding the Lazy H to get your antenna tuner to match it. 3) A 1/2 wave dipole will beat the Lazy H 99.99 percent of the time in it's favored direction even if the Lazy H is given a 20 foot height advantage over the dipole. 4) An extended double zepp with a 450 ohm matching section back to a 1:1 balun and then to 50 ohm coax cut for the same frequency and hung from the same ropes previously used to support the Lazy H will blow the Lazy H in the dirt. In a nutshell, this antenna sucks! Michael Rawls KS4HY Tried mounting it horizontally ? -- Best Regards: * * * * * * * * * * * * * Baron. Hi Michael, I'm sorry to hear you think the lazy-H sucks. I used one on 20m years ago and it worked just fine--and no trouble in matching it with a tuner. However, I have a suggestion: Let's say you space the upper and lower radiating elements by 180°, which is 1/2wl. If you now use 450-ohm window line, the velocity factor for the line attaching the two elements together makes the electrical length of the line greater than 1/2wl, which means the phasing between the upper and lower elements is no longer correct, and therefore will not provide the expected gain. I'm not sure how much phasing error that will produce, but it's an issue you should consider. Correctly constructed, the lazy-H will definitely out perform a 1/2wl dipole, so if it doesn't for you there is sum ting definitely wong! If you feed at the center of the line connecting the two radiating elements the phasing will be correct regardless of the velocity factor, because the length from the center feed point on the connecting line will be the same from that point to each radiating element. With this configuration of feeding don't put a twist in the connecting line--the two radiating elements MUST be fed IN PHASE! If they're fed out of phase the array will look like an Adcock direction- finding antenna, with a deep null in the radiation pattern in the broadside direction. Just my thoughts, Walt, W2DU |
#5
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The Lazy H does not seem to exhibit any gain over a dipole in thereal world
On May 30, 9:31*pm, Michael wrote:
* Thanks for your input Walt, but I already thought of those things. I definitely made the antenna correctly. *According to the ARRL handbook when center feeding the Lazy H increasing the spacing beyond 1/2 wave makes the gain go up until the spacing reaches 5/8ths wave. The handbooks states 5.9 dbd gain for 1/2 wave spacing and 6.7 dbd for 5/8ths wave spacing. *In the real world this antenna does not have any gain over a 1/2 wave dipole when center fed with 450 ohm ladder line all the way back to the tuner. *The phasing was correct. On 14 MHz where it becomes two stacked dipoles the SWR comes down and the performance goes up, but on 28 MHz it consistently lags behind a dipole. *I rebuilt this antenna twice. *If you actually go to the trouble of making one for 10 meters, and compare it to a real world 28 Mhz 1/2 wave dipole, the Lazy H will fall far short of the predicted gain. * I have been a ham since 1986. *I wondered why I had heard so few hams using a Lazy H, and the one time I recalled hearing one the signal was weaker than the other hams using a dipole. *I assumed at the time that I must have been off the side of the other ham's Lazy H, but after my real world test who knows. * I'm going to remove the center feed from the antenna this week, and rework the Lazy H for end feed with a twist, a matching stub, and 1/2 wave spacing. *Hopefully the end fed version of the Lazy H will live up to it's text book gain. *I'd really like to have that 6 dbd gain along with the nulls off the sides, Michael Rawls KS4HY On May 30, 5:48*pm, walt wrote: On May 30, 2:44*pm, Baron wrote: Michael Inscribed thus: * Well I've worked with the center fed Lazy H antenna design on 10 meters for several few weeks now. *I tried 1/2 wave spacing between the top and bottom elements, 5/8th wave spacing between the top and bottom elements, I put it up at 40 feet and 50 feet at the top wire, I tried different lengths of 450 ohm feed-line, and this antenna consistently under performs a 1/2 wave dipole cut for the same frequency. *A simple 1/2 wave dipole consistently out performs the center fed version of Lazy H antenna even when the Lazy H is given a 20 foot height advantage over the lowly dipole. I even put up the Lazy H in two completely different locations over 180 miles apart. I also tried two completely different antenna tuners (Dentron MT-3000a and Drake MN-75 with the 4:1 balun installed). Out of over 200 A/B test the Lazy H antenna only out performed the dipole on one test with a station in Texas just before the propagation faded out for the day, The next day when the propagation was back I heard the same station on the same frequency and the dipole out performed the Lazy H for the rest of the day. * I'm not sure what special propagation mode is required for the Lazy H to have some gain through some pin hole direction, but the version of the Lazy H center fed with 450 ohm ladder line back to the antenna tuner is a complete failure. *I even re-built the antenna from scratch using a different piece 450 ladder line for the inter connecting piece. I also verified the length of each 1/2 wave section with a tape measure. I verified with an ohm meter that the top left element was connected to the bottom left element and the right top element was connected to the bottom right element. *I verified there was no unexpected connectivity between the left and right elements, and I verified both sides of the ladder line were connected back to the antenna tuner. *I made sure there was no twist in the ladder line connecting the top and bottom elements. * I would like to petition the ARRL to remove the center fed Lazy H from the antenna handbook as it clearly does not work as specified. *A lowly mono band dipole on the same design frequency will consistently out perform the center feed Lazy H even when the Lazy H is given a 20 foot height advantage on10 meters. * Before any of you reply with charts and graphs from EZNEC software, turn off your computer, go out in the back yard, and actually build a center fed Lazy H antenna with 450 ladder line all the way back to the antenna tuner. *Then do real world A/B comparisons with a plain old mono band dipole cut for the same frequency, and you will find I am telling the truth. *The center fed Lazy H does not have any gain over a 1/2 wave dipole broadside to the antenna. None. Here is what you will fine if you actually build the center fed Lazy H and compare it to a 1/2 wave mono band dipole cut for the same same frequency; 1) Your tuner will have to use extreme setting to match the Lazy H. 2) In some instances the tuner will not be able to match the Lazy H depending on the length of the ladder line feeding the antenna. You may have to increase or decrease the length of the ladder line feeding the Lazy H to get your antenna tuner to match it. 3) A 1/2 wave dipole will beat the Lazy H 99.99 percent of the time in it's favored direction even if the Lazy H is given a 20 foot height advantage over the dipole. 4) An extended double zepp with a 450 ohm matching section back to a 1:1 balun and then to 50 ohm coax cut for the same frequency and hung from the same ropes previously used to support the Lazy H will blow the Lazy H in the dirt. In a nutshell, this antenna sucks! Michael Rawls KS4HY Tried mounting it horizontally ? -- Best Regards: * * * * * * * * * * * * * Baron. Hi Michael, I'm sorry to hear you think the lazy-H sucks. I used one on 20m years ago and it worked just fine--and no trouble in matching it with a tuner. However, I have a suggestion: Let's say you space the upper and lower radiating elements by 180°, which is 1/2wl. If you now use 450-ohm window line, the velocity factor for the line attaching the two elements together makes the electrical length of the line greater than 1/2wl, which means the phasing between the upper and lower elements is no longer correct, and therefore will not provide the expected gain. I'm not sure how much phasing error that will produce, but it's an issue you should consider. Correctly constructed, the lazy-H will definitely out perform a 1/2wl dipole, so if it doesn't for you there is sum ting definitely wong! If you feed at the center of the line connecting the two radiating elements the phasing will be correct regardless of the velocity factor, because the length from the center feed point on the connecting line will be the same from that point to each radiating element. With this configuration of feeding don't put a twist in the connecting line--the two radiating elements MUST be fed IN PHASE! If they're fed out of phase the array will look like an Adcock direction- finding antenna, with a deep null in the radiation pattern in the broadside direction. Just my thoughts, Walt, W2DU One other thought, Michael, is that if you made the lazy-H with 1/2wl spacing for 20m and then use it on 10m, the spacing is now 1wl. I haven't seen any figures for that spacing, but isn't it possible that with that spacing the gain might not be what you expect? Especially if it works properly on 20m? Walt |
#6
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The Lazy H does not seem to exhibit any gain over a dipole in thereal world
On May 30, 10:37*pm, walt wrote:
On May 30, 9:31*pm, Michael wrote: * Thanks for your input Walt, but I already thought of those things. I definitely made the antenna correctly. *According to the ARRL handbook when center feeding the Lazy H increasing the spacing beyond 1/2 wave makes the gain go up until the spacing reaches 5/8ths wave. The handbooks states 5.9 dbd gain for 1/2 wave spacing and 6.7 dbd for 5/8ths wave spacing. *In the real world this antenna does not have any gain over a 1/2 wave dipole when center fed with 450 ohm ladder line all the way back to the tuner. *The phasing was correct. On 14 MHz where it becomes two stacked dipoles the SWR comes down and the performance goes up, but on 28 MHz it consistently lags behind a dipole. *I rebuilt this antenna twice. *If you actually go to the trouble of making one for 10 meters, and compare it to a real world 28 Mhz 1/2 wave dipole, the Lazy H will fall far short of the predicted gain. * I have been a ham since 1986. *I wondered why I had heard so few hams using a Lazy H, and the one time I recalled hearing one the signal was weaker than the other hams using a dipole. *I assumed at the time that I must have been off the side of the other ham's Lazy H, but after my real world test who knows. * I'm going to remove the center feed from the antenna this week, and rework the Lazy H for end feed with a twist, a matching stub, and 1/2 wave spacing. *Hopefully the end fed version of the Lazy H will live up to it's text book gain. *I'd really like to have that 6 dbd gain along with the nulls off the sides, Michael Rawls KS4HY On May 30, 5:48*pm, walt wrote: On May 30, 2:44*pm, Baron wrote: Michael Inscribed thus: * Well I've worked with the center fed Lazy H antenna design on 10 meters for several few weeks now. *I tried 1/2 wave spacing between the top and bottom elements, 5/8th wave spacing between the top and bottom elements, I put it up at 40 feet and 50 feet at the top wire, I tried different lengths of 450 ohm feed-line, and this antenna consistently under performs a 1/2 wave dipole cut for the same frequency. *A simple 1/2 wave dipole consistently out performs the center fed version of Lazy H antenna even when the Lazy H is given a 20 foot height advantage over the lowly dipole. I even put up the Lazy H in two completely different locations over 180 miles apart. I also tried two completely different antenna tuners (Dentron MT-3000a and Drake MN-75 with the 4:1 balun installed). Out of over 200 A/B test the Lazy H antenna only out performed the dipole on one test with a station in Texas just before the propagation faded out for the day, The next day when the propagation was back I heard the same station on the same frequency and the dipole out performed the Lazy H for the rest of the day. * I'm not sure what special propagation mode is required for the Lazy H to have some gain through some pin hole direction, but the version of the Lazy H center fed with 450 ohm ladder line back to the antenna tuner is a complete failure. *I even re-built the antenna from scratch using a different piece 450 ladder line for the inter connecting piece. I also verified the length of each 1/2 wave section with a tape measure. I verified with an ohm meter that the top left element was connected to the bottom left element and the right top element was connected to the bottom right element. *I verified there was no unexpected connectivity between the left and right elements, and I verified both sides of the ladder line were connected back to the antenna tuner. *I made sure there was no twist in the ladder line connecting the top and bottom elements. * I would like to petition the ARRL to remove the center fed Lazy H from the antenna handbook as it clearly does not work as specified. *A lowly mono band dipole on the same design frequency will consistently out perform the center feed Lazy H even when the Lazy H is given a 20 foot height advantage on10 meters. * Before any of you reply with charts and graphs from EZNEC software, turn off your computer, go out in the back yard, and actually build a center fed Lazy H antenna with 450 ladder line all the way back to the antenna tuner. *Then do real world A/B comparisons with a plain old mono band dipole cut for the same frequency, and you will find I am telling the truth. *The center fed Lazy H does not have any gain over a 1/2 wave dipole broadside to the antenna. None. Here is what you will fine if you actually build the center fed Lazy H and compare it to a 1/2 wave mono band dipole cut for the same same frequency; 1) Your tuner will have to use extreme setting to match the Lazy H. 2) In some instances the tuner will not be able to match the Lazy H depending on the length of the ladder line feeding the antenna. You may have to increase or decrease the length of the ladder line feeding the Lazy H to get your antenna tuner to match it. 3) A 1/2 wave dipole will beat the Lazy H 99.99 percent of the time in it's favored direction even if the Lazy H is given a 20 foot height advantage over the dipole. 4) An extended double zepp with a 450 ohm matching section back to a 1:1 balun and then to 50 ohm coax cut for the same frequency and hung from the same ropes previously used to support the Lazy H will blow the Lazy H in the dirt. In a nutshell, this antenna sucks! Michael Rawls KS4HY Tried mounting it horizontally ? -- Best Regards: * * * * * * * * * * * * * Baron. Hi Michael, I'm sorry to hear you think the lazy-H sucks. I used one on 20m years ago and it worked just fine--and no trouble in matching it with a tuner. However, I have a suggestion: Let's say you space the upper and lower radiating elements by 180°, which is 1/2wl. If you now use 450-ohm window line, the velocity factor for the line attaching the two elements together makes the electrical length of the line greater than 1/2wl, which means the phasing between the upper and lower elements is no longer correct, and therefore will not provide the expected gain. I'm not sure how much phasing error that will produce, but it's an issue you should consider. Correctly constructed, the lazy-H will definitely out perform a 1/2wl dipole, so if it doesn't for you there is sum ting definitely wong! If you feed at the center of the line connecting the two radiating elements the phasing will be correct regardless of the velocity factor, because the length from the center feed point on the connecting line will be the same from that point to each radiating element. With this configuration of feeding don't put a twist in the connecting line--the two radiating elements MUST be fed IN PHASE! If they're fed out of phase the array will look like an Adcock direction- finding antenna, with a deep null in the radiation pattern in the broadside direction. Just my thoughts, Walt, W2DU One other thought, Michael, is that if you made the lazy-H with 1/2wl spacing for 20m and then use it on 10m, the spacing is now 1wl. I haven't seen any figures for that spacing, but isn't it possible that with that spacing the gain might not be what you expect? Especially if it works properly on 20m? Walt Hi Walt, I initially made the Lazy H for 5/8th wave spacing on 10 meters. When that did not work I reduced the spacing to 1/2 wave spacing on 10 meters. The 4 half wave elements are 1/2 waves on 10 meters. The antenna design is really pretty simple. I did make some contacts with this antenna and I received some good reports, but the dipole consistently out performed the Lazy H, There was one contact in Bermuda that said the Lazy H put in a stronger signal from South Carolina, but there was alot of fading at the time. Even when the Bermuda contact said the Lazy H put in the stronger signal the dipole was receiving the stronger signal from Bermuda. Michael |
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The Lazy H does not seem to exhibit any gain over a dipole in the real world
"Baron" wrote in message ... Michael Inscribed thus: Tried mounting it horizontally ? -- Best Regards: Baron. I looked at that antenna in a handbook years ago. Could not tell from that how it is mounted. Do you mount the elements one over the top of the other, or do you mount them sideways like a 2 element horizontal beam ? |
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The Lazy H does not seem to exhibit any gain over a dipole in thereal world
On May 30, 10:57*pm, "Ralph Mowery"
wrote: "Baron" wrote in message ... Michael Inscribed thus: Tried mounting it horizontally ? -- Best Regards: * * * * * * * * * * * * *Baron. I looked at that antenna in a handbook years ago. *Could not tell from that how it is mounted. *Do you mount the elements one over the top of the other, or do you mount them sideways like a 2 element horizontal beam ? Yes. It is mounted horizontally. |
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The Lazy H does not seem to exhibit any gain over a dipole inthe real world
I sort of think also, the Lazy H (think colinear?) should be fed and
phased with 75 ohm line. On Mon, 30 May 2011 14:48:45 -0700, walt wrote: If you feed at the center of the line connecting the two radiating elements the phasing will be correct regardless of the velocity factor, because the length from the center feed point on the connecting line will be the same from that point to each radiating element. With this configuration of feeding don't put a twist in the connecting line--the two radiating elements MUST be fed IN PHASE! If they're fed out of phase the array will look like an Adcock direction- finding antenna, with a deep null in the radiation pattern in the broadside direction. Just my thoughts, Walt, W2DU |
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The Lazy H does not seem to exhibit any gain over a dipole in thereal world
On May 31, 11:07*am, Wond wrote:
* * *I sort of think also, the Lazy H (think colinear?) should be fed and phased with 75 ohm line. On Mon, 30 May 2011 14:48:45 -0700, walt wrote: If you feed at the center of the line connecting the two radiating elements the phasing will be correct regardless of the velocity factor, because the length from the center feed point on the connecting line will be the same from that point to each radiating element. With this configuration of feeding don't put a twist in the connecting line--the two radiating elements MUST be fed IN PHASE! If they're fed out of phase the array will look like an Adcock direction- finding antenna, with a deep null in the radiation pattern in the broadside direction. Just my thoughts, Walt, W2DU Another point to consider, Mark, is that the azimuth beam width is narrower with the lazy-H than that of the dipole. So perhaps the apparent lower signal level is in directions off the side of the radiation pattern, where one would expect the signal level to be lower than that of the dipole at the same angle. Walt |
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