On 10/12/2014 10:20 AM, John S wrote:
On 10/12/2014 12:41 AM, wrote:
Jeff Liebermann wrote:
On Sat, 11 Oct 2014 18:04:07 -0000, wrote:

Jeff Liebermann wrote:

snip

Speaking of dipole antennas, I did this study a while back:
http://802.11junk.com/jeffl/antennas/vertical-dipole/index.html
Animated version:
http://802.11junk.com/jeffl/antennas/vertical-dipole/slides/animated-v-dipole.html

It's a 1/2 wave dipole at various heights above a real ground. Any
semblance to textbook dipole pattern is long gone.

Yep, ground has a huge effect on some types of antennas.

An instructive slide show would be the vertical pattern of a horizontal
1/2 dipole at .1, .2, ... .5 wavelengths over ground.

Another one would be a 3 element beam at those heights.

I can do both of these, but I'm busy/lazy this weekend. I also can't
find the program I used to create the annimated GIF file. Argh. It
would also be helpful if someone would specify the frequency range of
interest.

It doesn't matter if everything is done in wavelengths.

I guess there are some who would want to see that a 160 meter dipole
at say .2 wavelengths high has the same pattern as a 2 meter dipole
at .2 wavelengths if for no other reason than to be assured the effects
are frequency independant.

Something else might be interesting; include the effects of sag
(centenary) in a wire antenna. Has anyone done that? I mean, using EZNEC
or NEC modeling.


Arrgh! Catenary instead of what I posted. Damn spell checker is dumb on
a lot of math and engineering terms. Sorry

John S wrote in :

Catenary instead of what I posted.

Yes. I should have read your second post before my first reply..

On 10/12/2014 11:19 AM, Lostgallifreyan wrote:
John S wrote in :

Catenary instead of what I posted.

Yes. I should have read your second post before my first reply..

No problem. Your reply was completely appropriate. We might be just a
bit out of sink (he, he) sync. Let's not get too serious.

John S wrote in :

On 10/12/2014 11:19 AM, Lostgallifreyan wrote:
John S wrote in :

Catenary instead of what I posted.

Yes. I should have read your second post before my first reply..

No problem. Your reply was completely appropriate. We might be just a
bit out of sink (he, he) sync. Let's not get too serious.



I try not to. It's one reason I had a bit of off-topic fun with Douglas Adams
last night when the opportunity arose.

On 10/12/2014 12:13 PM, Lostgallifreyan wrote:
John S wrote in :

On 10/12/2014 11:19 AM, Lostgallifreyan wrote:
John S wrote in :

Catenary instead of what I posted.

Yes. I should have read your second post before my first reply..

No problem. Your reply was completely appropriate. We might be just a
bit out of sink (he, he) sync. Let's not get too serious.



I try not to. It's one reason I had a bit of off-topic fun with Douglas Adams
last night when the opportunity arose.


I'm sorry, I don't know that person. Should I?

John S wrote in :

I try not to. It's one reason I had a bit of off-topic fun with Douglas
Adams last night when the opportunity arose.


I'm sorry, I don't know that person. Should I?


Writer of The Hitch-Hiker's Guide To The Galaxy, and others. He's fairly
popular in technical and scientific circles so he gets mentioned at
surprising and sometimes very funny moments. Aquired taste actually, but I
was lucky enough to aquire it early.

On 10/12/2014 12:26 PM, Lostgallifreyan wrote:
John S wrote in :

I try not to. It's one reason I had a bit of off-topic fun with Douglas
Adams last night when the opportunity arose.


I'm sorry, I don't know that person. Should I?


Writer of The Hitch-Hiker's Guide To The Galaxy, and others. He's fairly
popular in technical and scientific circles so he gets mentioned at
surprising and sometimes very funny moments. Aquired taste actually, but I
was lucky enough to aquire it early.


I know of Hitch-Hiker's Guide To The Galaxy, but I have never watched.
Probably my loss. In any case, let's do the antenna thing. Yes?