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Mike Coslo[_2_] June 27th 11 02:19 PM

20m FD Dipole
 
On 6/27/2011 12:04 AM, John S wrote:
On 6/26/2011 10:34 PM, Mike Coslo wrote:


And we get that higher education in a netnews group? I enjoy this group,
but it's the equivalent to getting marriage advice at a bar. Maybe good,
but just as likely really bad.


Maybe you are already educated beyond what is available here. If so,
good for you.


Have you tried out rec.radio.amateur.policy? I think it's your kind of
group.

- 73 de Mike N3LI -

Mike Coslo[_2_] June 27th 11 02:33 PM

20m FD Dipole
 
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 -


John S June 27th 11 04:40 PM

20m FD Dipole
 
On 6/27/2011 8:19 AM, Mike Coslo wrote:
On 6/27/2011 12:04 AM, John S wrote:
On 6/26/2011 10:34 PM, Mike Coslo wrote:


And we get that higher education in a netnews group? I enjoy this group,
but it's the equivalent to getting marriage advice at a bar. Maybe good,
but just as likely really bad.


Maybe you are already educated beyond what is available here. If so,
good for you.


Have you tried out rec.radio.amateur.policy? I think it's your kind of
group.

- 73 de Mike N3LI -


And maybe you should try out rec.radio.amateur.know_it_all. I'm sure
you'd be in good company.

John

W8CCW June 27th 11 06:01 PM

20m FD Dipole
 
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.


tom June 28th 11 03:19 AM

20m FD Dipole
 
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

Mike Coslo[_2_] June 28th 11 04:14 AM

20m FD Dipole
 
On 6/27/2011 11:40 AM, John S wrote:
On 6/27/2011 8:19 AM, Mike Coslo wrote:


Have you tried out rec.radio.amateur.policy? I think it's your kind of
group.

- 73 de Mike N3LI -


And maybe you should try out rec.radio.amateur.know_it_all. I'm sure
you'd be in good company.


Why John, you must be pulling me leg here. I looked for that group, and
couldn't find it. 8^)

- 73 de Mike N3LI -

Mike Coslo[_2_] June 28th 11 04:20 AM

20m FD Dipole
 
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 -

John S June 28th 11 04:35 AM

20m FD Dipole
 
On 6/27/2011 10:14 PM, Mike Coslo wrote:
On 6/27/2011 11:40 AM, John S wrote:
On 6/27/2011 8:19 AM, Mike Coslo wrote:


Have you tried out rec.radio.amateur.policy? I think it's your kind of
group.

- 73 de Mike N3LI -


And maybe you should try out rec.radio.amateur.know_it_all. I'm sure
you'd be in good company.


Why John, you must be pulling me leg here. I looked for that group, and
couldn't find it. 8^)

- 73 de Mike N3LI -


Okay. You got me.

John

tom June 29th 11 02:34 AM

20m FD Dipole
 
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

Sal M. Onella[_2_] June 29th 11 02:39 AM

20m FD Dipole
 
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.


This is only a test post. I have responded to this particular item
twice, once on Sunday and once yesterday. Neither one showed up.
Nothing in what I said would have been censored for any reason. Odd.
I think it said post was successful. I'm checking that now and will
wait to see if this appears in the group.

"Sal"


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