# Tree based antenna



## lagerstedt (Oct 16, 2005)

Some time ago I read an article regarding a WW1 US army engineer who designed a antenna that was placed at the base of a large tree trunk and consisted of a coil [of x turns and y dia] around the tree base, a vaiable capacitor some other bits and pieces all of which were earthed. Cannot remember to much more about it or the science behind his design other than it worked. I believe the freq was at or near 500 kcs.

An RF current radiates out from a normal antenna depending on a number of factors however I am stumped on this one. Have any of you bright sparks heard of the design or the US Army Engineer who designed it?. Mean time I will keep looking for the orginal article.

Regards
Blair
Central Hawkes Bay 
NZ


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## Coastie (Aug 24, 2005)

That's an interesting one! Can't say as I have ever heard of it.


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## tunatownshipwreck (Nov 9, 2005)

Sounds like a beverage antenna. I'm not making this up. You can probably find it in Google.


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## Doug Shaw (Jan 20, 2006)

Just google "tree antennas" to find some info on the subject. Apparently the idea was patented in the UK in 1917. This link looks particularly interesting.

Regards
Doug


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## spongebob (Dec 11, 2007)

Fascinating links on the net. 
Dead trees no good 
Trees with foliage better than bare,
It's a wonder that we did not see a few British ships sporting potted English Oaks on the boat deck!

Bob


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## NoMoss (Mar 14, 2007)

bob jenkins said:


> Fascinating links on the net.
> Dead trees no good
> Trees with foliage better than bare,
> It's a wonder that we did not see a few British ships sporting potted English Oaks on the boat deck!
> ...


P'raps the Irish Oak had one?


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## Billieboy (May 18, 2009)

Puts a new light on the main mast Christmas Tree!


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## King Ratt (Aug 23, 2005)

Just make sure the antenna is not "wooded" at its location.


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## Andy (Jan 25, 2004)

I've spoken to guys on the amateur bands who were using various unlkely items, including a tree, bicycle frame, metal fence, and metal guttering....along with a decent a.m.u.
Certainly some of these items have a history of being used in emergencies by the military... gutters for an antenna at 'safe houses' in unfriendly territory were often used.


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## charles henry (May 18, 2008)

During the early fifties there was an article in the IEE antenna section magazine, the US military were running further tests using trees as antennae, as I remember the article the tests discovered nothing new, a tree was a lousy antenna.

A Beveridge antenna is a VERY low and VERY long antenna used for receiving and can be terminated or not. In the fifties I put one up in FORT CHURCHILL, MANITOBA to receive Coral Harbour teletype.
It was about 2.5 miles long and 15 feet off the ground, unterminated. The receiving frequency was (by memory) 128 khz. The transmitter was 1 kw.

de chas


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## 5TT (May 3, 2008)

I think that US army engineer belonged to an experimental *branch* of the US signal corps who were all *bark*ing mad.
The tree would have *sap*ped most of the transmitter power and that's probably what *stump*ed him too, he never got to the *root* of the problem.
If only he'd read the *leaf*let.

= Adrian +


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## charles henry (May 18, 2008)

*pun*



5TT said:


> I think that US army engineer belonged to an experimental *branch* of the US signal corps who were all *bark*ing mad.
> The tree would have *sap*ped most of the transmitter power and that's probably what *stump*ed him too, he never got to the *root* of the problem.
> If only he'd read the *leaf*let.
> 
> = Adrian +


Oh Lord, save us from PUNishment
de chas


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## Pat Kennedy (Apr 14, 2007)

My son, who works for a firm that installs mobile phone masts all over the UK, tells me that for the last few years, they have been using masts that are designed to look like real trees, for use in 'sensitive' areas.
I have yet to see one, which proves that the camouflage really works!
Pat


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## Ron Stringer (Mar 15, 2005)

Pat Kennedy said:


> My son, who works for a firm that installs mobile phone masts all over the UK, tells me that for the last few years, they have been using masts that are designed to look like real trees, for use in 'sensitive' areas.
> I have yet to see one...


Shoulda gone to Specsavers, Pat[=P] 

There are plenty of them around, usually sticking out like sore thumbs on higher ground where there are no other trees! They resemble a tree that has been in a losing fight with a tree surgeon - lots of thick branches that have been sawn off near to the trunk.


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## spongebob (Dec 11, 2007)

Those private aerials at sea. I had an old 15 foot surf casting fishing rod made up of three sections.
Poked out my porthole with a light weight streaming conductor it worked better than most aerials and doubled as a great socks and undies clothes line until the top section worked loose.

Bob


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## lagerstedt (Oct 16, 2005)

Thanks to you bright sparks.

The guy I was looking for was Gen George O Squiers, [1865 to 1934] Chief Signals Officer, US Signals Corps. 

Still not sure how it works.

Regards
Blair
Central Hawkes Bay
NZ


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## Pat Kennedy (Apr 14, 2007)

Ron Stringer said:


> Shoulda gone to Specsavers, Pat[=P]
> 
> There are plenty of them around, usually sticking out like sore thumbs on higher ground where there are no other trees! They resemble a tree that has been in a losing fight with a tree surgeon - lots of thick branches that have been sawn off near to the trunk.


Ron, 
Maybe you live in a more sensitive area than me, I have never seen anything like you describe. 
Pat(Thumb)


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## spongebob (Dec 11, 2007)

Pat, give it a hug then you will tell the difference


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## Andy (Jan 25, 2004)

Pat Kennedy said:


> Ron,
> Maybe you live in a more sensitive area than me, I have never seen anything like you describe.
> Pat(Thumb)


I've seen them in fairly leafy areas down here (home counties)... and I have to agree with Ron, they look like a tree that has been in the blast radius of a nuclear device.

However, they maybe a fraction better than a lattice tower on the eyes.


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## 5TT (May 3, 2008)

> The guy I was looking for was Gen George O Squiers, [1865 to 1934] Chief Signals Officer, US Signals Corps.


I'm quite sure Gen George O Squires was not barking mad, so I wish to retract my theory, which was mine ... errrrrr hem ... 

= Adrian +


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## Naytikos (Oct 20, 2008)

I have tried using a few different trees as antennae. They don't really work for receiving but, by connecting it as an L-matched quarter-wave, a coconut tree will accept power at HF frequencies if it is tall enough. Best I have managed is into Florida, around 500 miles away, on 14MHz.
An on-going project I have is to conduct research into the resonant properties of certain tree-leaves at S-band frequencies. The significance is that, for example, the leaf of a sea-grape tree will absorb a frequency of 2.59GHz and thus block the signal path, while 2.596GHz is unaffected. All to do with the size of the cellular structure I think; hence the research.


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## Mimcoman (May 18, 2008)

I seem to remember an article in Wireless World in the 70s (?) whereby an Indian engineer tried feeding UHF to palm fronds, in an attempt to find out if the fronds would act as log periodics. If I remember correctly, they did radiate and there was some directivity, but the humidity and the presence and amount of tree sap also had some effect.


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## Mimcoman (May 18, 2008)

spongebob said:


> Those private aerials at sea. I had an old 15 foot surf casting fishing rod made up of three sections.
> Poked out my porthole with a light weight streaming conductor it worked better than most aerials and doubled as a great socks and undies clothes line until the top section worked loose.
> 
> Bob



....and I put up a set of dipoles with a common centre, cut for the HF broadcast bands and strung between the support masts on the aft end of the boat deck, feeding the Pantenna. Worked very well and had no effect on the DF. The OM made me take them down. Can't understand why he didn't like them- I thought they looked really good...


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## Finbar O'Connor (Sep 26, 2008)

Regarding feeding power to a tree for use as an antenna, there is an
excellent web site showing how it is done and making reference to the
research background to this type of antenna.
The are lots of photographs, which shows a very large wide spaced coil at the base of the tree and the matching system.
I would need to search again for this web site to find it, but you should
be able to find this North American guys work on a working system

Best regards
Finbar EI0CF


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## Finbar O'Connor (Sep 26, 2008)

Here is the link to a tree antenna system for the 600 m ie 500 khz
band.
This is the web link you are looking for.......

http://w5jgv.com/tree_antenna/index.htm

Enjoy the article and good luck with your own experiments.

Finbar EI0CF Malin Head, Ireland.


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## lagerstedt (Oct 16, 2005)

Thanks Finbar
The General has some 20 or more patents with his name attached to them and started working on this idea in the early 1900's. He was looking at a system to assisted both the local people and the armed forces in times of emergency with short range communications. From all accounts it worked over short ranges using telephony and telegraphy. Not to bad for the early 1900's.

Regards
Blair
Central Hawkes Bay
NZ


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## Finbar O'Connor (Sep 26, 2008)

Hello Blair,

Yes sounds great, considering just how far back that is radio history.

No suitable trees around here to try a similar system. At present 
experimenting with a 200 metre loop on 600m, but it does not compare
with the main vertical antenna which is 22 metres high and heavily top loaded.
Best regards
Finbar EI0CF


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