Home |
Search |
Today's Posts |
|
#1
![]() |
|||
|
|||
![]()
On Jun 24, 6:16*pm, "Sal M. Onella" wrote:
I've participated in Field Day every year since 1993, when I was first licensed. *Because I had a big 2m beam, I worked that band aggressively, sometimes making the most QSOs. Unfortunately we lost our hilltop FD site in 2009 and the 2m production "down low" was disappointing in '09 and '10. This year some youngsters want to work 2m, so I'm moving to HF, 20m being the most promising, I think. *With the help of EZNEC (evaluation version), I modeled a promising 20m dipole at 30'. It's almost exactly 75 ohms resistive at the freqs I want to use and I'm going to feed it with RG-6, 0.7 dB/100 feet. My radio has an internal tuner to match the 75-ohm cable, if I need it. I'll report the results. "Sal" KD6VKW ("Vicious Killer Weasel") wow, it takes eznec to model a dipole for field day now? not that many years ago i ran a competition at field day... given a hunk of coax(with one connector installed), a roll of wire, and some random pieces of rope, cut a 10m dipole, get it up in the air, and make a contact. no eznec, a tape measure if you really wanted it, and who knows what the coax was. |
#2
![]() |
|||
|
|||
![]()
On Sat, 25 Jun 2011 03:59:55 -0700 (PDT), dave wrote:
On Jun 24, 6:16*pm, "Sal M. Onella" wrote: I've participated in Field Day every year since 1993, when I was first licensed. *Because I had a big 2m beam, I worked that band aggressively, sometimes making the most QSOs. Unfortunately we lost our hilltop FD site in 2009 and the 2m production "down low" was disappointing in '09 and '10. This year some youngsters want to work 2m, so I'm moving to HF, 20m being the most promising, I think. *With the help of EZNEC (evaluation version), I modeled a promising 20m dipole at 30'. It's almost exactly 75 ohms resistive at the freqs I want to use and I'm going to feed it with RG-6, 0.7 dB/100 feet. My radio has an internal tuner to match the 75-ohm cable, if I need it. I'll report the results. "Sal" KD6VKW ("Vicious Killer Weasel") wow, it takes eznec to model a dipole for field day now? not that many years ago i ran a competition at field day... given a hunk of coax(with one connector installed), a roll of wire, and some random pieces of rope, cut a 10m dipole, get it up in the air, and make a contact. no eznec, a tape measure if you really wanted it, and who knows what the coax was. You take all the fun out of a guy's efforts. |
#3
![]() |
|||
|
|||
![]()
On Jun 25, 3:51*pm, Eskay wrote:
On Sat, 25 Jun 2011 03:59:55 -0700 (PDT), dave wrote: On Jun 24, 6:16*pm, "Sal M. Onella" wrote: I've participated in Field Day every year since 1993, when I was first licensed. *Because I had a big 2m beam, I worked that band aggressively, sometimes making the most QSOs. Unfortunately we lost our hilltop FD site in 2009 and the 2m production "down low" was disappointing in '09 and '10. This year some youngsters want to work 2m, so I'm moving to HF, 20m being the most promising, I think. *With the help of EZNEC (evaluation version), I modeled a promising 20m dipole at 30'. It's almost exactly 75 ohms resistive at the freqs I want to use and I'm going to feed it with RG-6, 0.7 dB/100 feet. My radio has an internal tuner to match the 75-ohm cable, if I need it. I'll report the results. "Sal" KD6VKW ("Vicious Killer Weasel") wow, it takes eznec to model a dipole for field day now? *not that many years ago i ran a competition at field day... given a hunk of coax(with one connector installed), a roll of wire, and some random pieces of rope, cut a 10m dipole, get it up in the air, and make a contact. *no eznec, a tape measure if you really wanted it, and who knows what the coax was. You take all the fun out of a guy's efforts. too many people spend all their time analyzing antennas and no time using them. |
#4
![]() |
|||
|
|||
![]()
On 6/26/2011 6:44 AM, dave wrote:
On Jun 25, 3:51 pm, wrote: On Sat, 25 Jun 2011 03:59:55 -0700 (PDT), dave wrote: On Jun 24, 6:16 pm, "Sal M. wrote: I've participated in Field Day every year since 1993, when I was first licensed. Because I had a big 2m beam, I worked that band aggressively, sometimes making the most QSOs. Unfortunately we lost our hilltop FD site in 2009 and the 2m production "down low" was disappointing in '09 and '10. This year some youngsters want to work 2m, so I'm moving to HF, 20m being the most promising, I think. With the help of EZNEC (evaluation version), I modeled a promising 20m dipole at 30'. It's almost exactly 75 ohms resistive at the freqs I want to use and I'm going to feed it with RG-6, 0.7 dB/100 feet. My radio has an internal tuner to match the 75-ohm cable, if I need it. I'll report the results. "Sal" KD6VKW ("Vicious Killer Weasel") wow, it takes eznec to model a dipole for field day now? not that many years ago i ran a competition at field day... given a hunk of coax(with one connector installed), a roll of wire, and some random pieces of rope, cut a 10m dipole, get it up in the air, and make a contact. no eznec, a tape measure if you really wanted it, and who knows what the coax was. You take all the fun out of a guy's efforts. too many people spend all their time analyzing antennas and no time using them. And some people spend all their time complaining about other people analyzing antennas. Take your own advice. |
#5
![]() |
|||
|
|||
![]()
On 6/26/2011 6:44 AM, dave wrote:
On Jun 25, 3:51 pm, wrote: On Sat, 25 Jun 2011 03:59:55 -0700 (PDT), dave wrote: wow, it takes eznec to model a dipole for field day now? not that many years ago i ran a competition at field day... given a hunk of coax(with one connector installed), a roll of wire, and some random pieces of rope, cut a 10m dipole, get it up in the air, and make a contact. no eznec, a tape measure if you really wanted it, and who knows what the coax was. You take all the fun out of a guy's efforts. too many people spend all their time analyzing antennas and no time using them. That is a disease that affects, as a SWAG, about 80% of the core population here. Then there are the people that ask questions because they are trying to actually build something. Who almost always get what is effectively GobbldeeGook in response. All they just want to know how to make something that is "OK, works good enough" and they have to wade through dozens of useless responses to _maybe_ get one that's worthwhile. Welcome to rraa, where no one "important" ever agrees. tom K0TAR |
#6
![]() |
|||
|
|||
![]()
On 6/27/2011 10:19 PM, tom wrote:
Then there are the people that ask questions because they are trying to actually build something. Who almost always get what is effectively GobbldeeGook in response. Hi Tom, This reminds me, is Art still around? I hope nothing has happened to the old gent. (I've been absent for several months) - 73 de Mike N3LI - |
#7
![]() |
|||
|
|||
![]()
On 6/27/2011 10:20 PM, Mike Coslo wrote:
On 6/27/2011 10:19 PM, tom wrote: Then there are the people that ask questions because they are trying to actually build something. Who almost always get what is effectively GobbldeeGook in response. Hi Tom, This reminds me, is Art still around? I hope nothing has happened to the old gent. (I've been absent for several months) - 73 de Mike N3LI - Haven't seen him since roughly the new year. His protege is back though. tom K0TAR |
#8
![]() |
|||
|
|||
![]()
On Jun 25, 8:51*am, Eskay wrote:
On Sat, 25 Jun 2011 03:59:55 -0700 (PDT), dave wrote: On Jun 24, 6:16*pm, "Sal M. Onella" wrote: I've participated in Field Day every year since 1993, when I was first licensed. *Because I had a big 2m beam, I worked that band aggressively, sometimes making the most QSOs. Unfortunately we lost our hilltop FD site in 2009 and the 2m production "down low" was disappointing in '09 and '10. This year some youngsters want to work 2m, so I'm moving to HF, 20m being the most promising, I think. *With the help of EZNEC (evaluation version), I modeled a promising 20m dipole at 30'. It's almost exactly 75 ohms resistive at the freqs I want to use and I'm going to feed it with RG-6, 0.7 dB/100 feet. My radio has an internal tuner to match the 75-ohm cable, if I need it. I'll report the results. "Sal" KD6VKW ("Vicious Killer Weasel") wow, it takes eznec to model a dipole for field day now? *not that many years ago i ran a competition at field day... given a hunk of coax(with one connector installed), a roll of wire, and some random pieces of rope, cut a 10m dipole, get it up in the air, and make a contact. *no eznec, a tape measure if you really wanted it, and who knows what the coax was. You take all the fun out of a guy's efforts. Yeah, kinda, but that's all right. I already have four working dipoles up at home, each produced much as Dave describes; 40, 20, 20, 10. I was seeking optimization and I got it. Example: My TS-870 electronic display lights up five little dots for a 1.5:1 SWR. As installed, the new antenna gave me only three little dots -- most of it probably right at the back of the radio in the transition to 75 ohms. I am very, very pleased with the results. 20m was lit up like a Christmas tree all day and into the night. While operating 100W, I logged a new QSO every two to five minutes. (I'm nobody's idea of a contester.) Surprise -- broke a few pileups. I oriented the antenna for max toward 060 degrees True, the bulk of North America from San Diego. Putting up three guyed 30-foot poles was quite the adventure but it all worked. No blood loss, one blister. :-) "Sal" PS: TS-870 reported an untuned 3:1 SWR on 15m, which the tuner handled easily. Many QSOs on 15m. |
#9
![]() |
|||
|
|||
![]()
On 6/27/2011 12:44 AM, Sal M. Onella wrote:
I was seeking optimization and I got it. Example: My TS-870 electronic display lights up five little dots for a 1.5:1 SWR. As installed, the new antenna gave me only three little dots -- most of it probably right at the back of the radio in the transition to 75 ohms. I am very, very pleased with the results. The fun part of antenna modeling, at least for me, is seeing how close the real thing meets the design. We put up an antenna for FD, an 80 meter cut for the cw portion of the band, and hit it on the first try. As for folks tuning up rain gutters and wire salvaged from an old toaster, then making an antenna out of it, that's fun too, but the final result isn't likely to be optimum. - 73 de Mike N3LI - |
#10
![]() |
|||
|
|||
![]()
On Mon, 27 Jun 2011 09:33:23 -0400, Mike Coslo wrote:
On 6/27/2011 12:44 AM, Sal M. Onella wrote: I was seeking optimization and I got it. Example: My TS-870 electronic display lights up five little dots for a 1.5:1 SWR. As installed, the new antenna gave me only three little dots -- most of it probably right at the back of the radio in the transition to 75 ohms. I am very, very pleased with the results. The fun part of antenna modeling, at least for me, is seeing how close the real thing meets the design. We put up an antenna for FD, an 80 meter cut for the cw portion of the band, and hit it on the first try. As for folks tuning up rain gutters and wire salvaged from an old toaster, then making an antenna out of it, that's fun too, but the final result isn't likely to be optimum. - 73 de Mike N3LI - I use EZNEC 5 nearly every day. It saves me time & money. I can minimize my physical work as well. At 71 years old that is getting more important every day. Last week I took down my Fan of dipoles and put up a 40m half wave in series with an 80 meter half wave, fed at 33% from one end. The wire was handy and so was the room. What a waste and in 90 degree + weather too. If I had modelled it first, I would have done it. Hard to feed everywhere and the low activity seem to endorse the computed patterns. I ran an inverted Vee through EZ5 with 43 foot wires on each side and it looked as good as anything on 40 & 80M and was easy to tune about anywhere. The testing has supported that the 30M and up patterns are not nearly as useful as the corresponding dipoles, but it does work everywhere. I got the 43 foot wires by simply folding the excess from an 80M dipole and taping them. Nothing permanent, no $ spent. I will likely keep this for 40 & 80. Probably back to adding in a couple of dipoles for 30 & 17 in a fan configuration while I consider my first venture into my first Quad effort. 20-15-10 are covered with an A3S Cushcraft at 60 feet. I don't understand it, but it works good. |
Reply |
|
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
Better than the fan dipole | Antenna | |||
80+40 MTR Dipole | Antenna | |||
sgc dipole? | Antenna | |||
Help with dipole please? | Homebrew | |||
80/40/30M dipole? | Antenna |