Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #11   Report Post  
Old May 19th 04, 02:14 AM
William Warren
 
Posts: n/a
Default

"JGBOYLES" wrote in message
...
Some years ago experiments have be done using trees as antennas. Where
can I find references about ? Do fellows here known about the results ?


Seems like I remember an article in the 70's in 73 magazine (what else?)
about this very subject. I don't have time to look back thru my old

mags., but
I bet the results indicated trees don't work well as antennas. If they

did, a
lot more hams would be using them. I don't think I have ever had a

contact
with someone using a tree.
73 Gary N4AST


Maybe we can open a new branch of science, and solve some knotty problems.

Please, don't say "What a sap!". This is serious: we've got a trunkful of
knowledge here in the group, and we can put the crown on this whole idea.

I'm not just barking at the moon.

Bill


  #12   Report Post  
Old May 19th 04, 02:43 AM
Fractenna
 
Posts: n/a
Default

Please, don't say "What a sap!". This is serious: we've got a trunkful of
knowledge here in the group, and we can put the crown on this whole idea.

I'm not just barking at the moon.

Bill


Tough finding many different tree species in OK. But everyone enjoys OK's wide
open spaces.

73,
Chip N1IR
  #13   Report Post  
Old May 19th 04, 03:56 AM
k4wge
 
Posts: n/a
Default

Richard Clark wrote in message . ..
On Tue, 18 May 2004 08:58:22 -0500, "Dave VanHorn"
wrote:

they are fractal,


Which then leads to one of many entries to this explicit topic found
in:
http://groups.google.com/groups?hl=e...com%26rnum%3D9

Yes; I knew when I made rocks and trees into antennas I was going to get
some flack.

which served ego rather more than technical discussion.

This thread still remains as one of the most comic pieces published in
this group and worth reading the 59 entries.



It may be the first time Cohen introduced "Jack", one of several of
the Fractal Personalities:

From: (Prozma)
Subject: YET ANOTHER BREAKTHROUGH ON TREES
Date: 1997/01/20
Message-ID: # 1/1
references:
organization: AOL
http://www.aol.com
newsgroups: rec.radio.amateur.antenna
x-admin:



Hello Chip;

I suggest you back off on this W8JITom fellow. He seems to make things
up
that you didn't say and refuses to try something as simple as knocking
a
nail into a tree. Perhaps he lacks the coax cable. I will turn the
filter
back on. Might do well for you to ignore all his responses as few seem
worthwhile.

People have been using trees for clandestine antennas since before
WWII.
As you point out it is not the best of antennas. For him to deny it is
at
least consistent for him.

As for your comment on libraries I heartily commend it. Everyone has
to
keep up if he is an engineer worth his salt. I remember going out of
my
way to get to Tech's library several times a year even when I lived
300
miles away.

Best to You and others here;

Jack
  #14   Report Post  
Old May 19th 04, 06:00 AM
Richard Clark
 
Posts: n/a
Default

On 18 May 2004 19:56:34 -0700, (k4wge) wrote:
From:
(Prozma)
Ah Yes, the Mutt of the Mutt 'n' Jeff comedy act.
  #15   Report Post  
Old May 19th 04, 06:32 AM
Claude Frantz
 
Posts: n/a
Default

Many thanks for all the responses.

I remember that in the experiment I have mentioned, the coupling to the
tree was via an toroidal coil which was mounted around the tree, the
tree beeing in the axis.

Sure, a tree cannot be a good antenna. Any "real" antenna will probably
always be better. But often the question is: no antenna at all or
anything which does not seem to be an antenna. Perhaps a tree can be
such a thing. Further, in portable operation, it is not always easy to
install a "real" antenna.

Claude



  #16   Report Post  
Old May 19th 04, 11:40 AM
Murray
 
Posts: n/a
Default

I regret I cannot give you an exzact reference but the WIA
magazine Amateur Radio, some years ago had such an article
and the results thereof. It worked quite well for what it was (a tree)
and there were even suggestions as to which species were better than
others! AFAIK it wasn't an April edition.

Some of the gum trees here are 150+ feet high and the trick seemed to
be tapping in at the right level from the ground.

Some unhelpfull folk later suggested the 8' of coax to the matching
network was the radiator :-(

I have no way of finding this info - maybe you can search the net?

Cheers
Murray vk4aok

Claude Frantz wrote:
Many thanks for all the responses.

I remember that in the experiment I have mentioned, the coupling to the
tree was via an toroidal coil which was mounted around the tree, the
tree beeing in the axis.

Sure, a tree cannot be a good antenna. Any "real" antenna will probably
always be better. But often the question is: no antenna at all or
anything which does not seem to be an antenna. Perhaps a tree can be
such a thing. Further, in portable operation, it is not always easy to
install a "real" antenna.

Claude


  #17   Report Post  
Old May 19th 04, 11:58 AM
Fractenna
 
Posts: n/a
Default

Sure, a tree cannot be a good antenna. Any "real" antenna will probably
always be better. But often the question is: no antenna at all or
anything which does not seem to be an antenna. Perhaps a tree can be
such a thing. Further, in portable operation, it is not always easy to
install a "real" antenna.

Claude


Trees are, as already noted, usable as VHF antennas when properly
'fed'...whether you should or shouldn't use a tree is your decision. It is
hardly a new idea. Certainly placing a bona fide VHF antenna--in the clear--on
top of the tree is the better of the two options.

The interesting question is: how does a tree compare to a ground-based
monopole?

There is a reason why VHF monopole antennas are not on the ground, whereas MF
ones are.

Experiment for more info. Many have been down this path before. I don't know a
sap or a chump in the bunch.

73,
Chip N1IR
  #18   Report Post  
Old May 20th 04, 10:02 AM
Mark Keith
 
Posts: n/a
Default

Claude Frantz wrote in message ...
Many thanks for all the responses.

I remember that in the experiment I have mentioned, the coupling to the
tree was via an toroidal coil which was mounted around the tree, the
tree beeing in the axis.

Sure, a tree cannot be a good antenna. Any "real" antenna will probably
always be better. But often the question is: no antenna at all or
anything which does not seem to be an antenna. Perhaps a tree can be
such a thing. Further, in portable operation, it is not always easy to
install a "real" antenna.

Claude


I've seen advertising in QRT for the latest new miracle sticks:

*SAPSUCKER 2000T®*.

and the mighty:

*BARKBURNER 9000TRX-DX®*

Note that the ground qualities will enhance automatically by using
such an treetenna. That is because most all dogs will stop and urinate
against the base of said device. Add a few beer drinking buddies to
the party, and you will be a dx chipper in no time. Squirrels can add
nests, which will act as additional top loading.
Beware of tree beetles, infections, etc.. After a while the treetenna
could become a:
*STUMPSTICK*
Gasp!
These have been proven to be inferior radiators due to the *stumphole
effect* to the rf as it encounters the many rings in the tree stump.
These proceed to turn the rf round and round ,like flushing a toilet,
and ploink, you blow the finals in your rig, due to a massive
*wormwood* pulse that flows back along your feeder to the rig and your
operating position. Usually a desk or table made of wood, which
further increases the potential of damage to the station.

MK
  #19   Report Post  
Old May 21st 04, 07:43 PM
Helmut Wabnig
 
Posts: n/a
Default

On Tue, 18 May 2004 10:26:59 +0200, Claude Frantz
wrote:

Some years ago experiments have be done using trees as antennas. Where
can I find references about ? Do fellows here known about the results ?

Claude

enter "tree antenna" into GOOGLE GROUPS, 17 000 hits,
needs some additional filtering , but here we go!


I used them trees, while I was a boy, to listen to medium wave radio
stations with my diode detector, a 60 mm nail, a hammer, some wire,
worked great, nail them in about 3 meters height.

S9 + 20 dB, for sure :-)

w.
Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Inverted ground plane antenna: compared with normal GP and low dipole. Serge Stroobandt, ON4BAA Antenna 8 February 24th 11 10:22 PM
Mobile Ant L match ? Henry Kolesnik Antenna 14 January 20th 04 04:08 AM
Poor quality low + High TV channels? How much dB in Preamp? lbbs Antenna 16 December 13th 03 03:01 PM


All times are GMT +1. The time now is 03:15 AM.

Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 RadioBanter.
The comments are property of their posters.
 

About Us

"It's about Radio"

 

Copyright © 2017