Loop Antenna
 

Does anyone have an idea regarding the affect of
a T shaped loop? I know that a circle has larger
ap then a delta loop or square loop. Would an effect
be realized with a T?

Bill
N1EY

William H. O'Hara, III wrote:
Does anyone have an idea regarding the affect of
a T shaped loop? I know that a circle has larger
ap then a delta loop or square loop. Would an effect
be realized with a T?

Bill
N1EY

Start at an extreme case for the T. If the two conductors of the T's
stem are close together, then your T loop's stem is going to act like
open feedline. If the two conductors of the T's top are close together,
then your T loop's top is going to act a folded dipole.

Opening parellel sides of the stem or/and the top makes the structure
move towards becoming a square (rectangular) assembly.

If you keep the lower end of the stem close together and widen the top
of the stem, then the T moves towards an inverted delta assembly.

Duane
N6JPO

I would think such an antenna would be difficult to adjust to avoid
adverse
phase interactions...

================================

On the other hand there are an equal number of advantageous interactions.

"William H. O'Hara, III" wrote in message
. 97.142...
Does anyone have an idea regarding the affect of
a T shaped loop? I know that a circle has larger
ap then a delta loop or square loop. Would an effect
be realized with a T?


sounds like a folded dipole. - and it should act like one too.
you'll find that if you can move the 'vertical' part of the 'T' (feedpoint)
using a pully setup, that the arrangement can be used for several bands.
put a 4-1 balun at the bottom of the T.



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"Hal Rosser" wrote in
:


"William H. O'Hara, III" wrote in
message
. 97.142...
Does anyone have an idea regarding the affect of
a T shaped loop? I know that a circle has larger
ap then a delta loop or square loop. Would an effect
be realized with a T?


sounds like a folded dipole. - and it should act like one
too. you'll find that if you can move the 'vertical' part
of the 'T' (feedpoint) using a pully setup, that the
arrangement can be used for several bands. put a 4-1 balun
at the bottom of the T.

What happens if I do this,

300 feet
--------------------
| | 1
| | 0
| 100 ft 100 ft| 0
|_____ ______| ft
| |
| | 9
| | 0
| | f
|_______| t
FEED


Any thoughts?

Thanks
Bill N1EY

The free demo version of EZNEC available from http://eznec.com can
easily answer questions just like this.

Roy Lewallen, W7EL


William H. O'Hara, III wrote:

What happens if I do this,

300 feet
--------------------
| | 1
| | 0
| 100 ft 100 ft| 0
|_____ ______| ft
| |
| | 9
| | 0
| | f
|_______| t
FEED


Any thoughts?

Thanks
Bill N1EY

Roy Lewallen wrote in
:

The free demo version of EZNEC available from
http://eznec.com can easily answer questions just like
this.


It refuses to calculate SWR due to multiple wires
running so close would create interactions.

Bill

There shouldn't be any problem with that antenna. Please send me the
description (.EZ) file as an email attachment, and I'll look it over.

Roy Lewallen, W7EL

William H. O'Hara, III wrote:
Roy Lewallen wrote in
:


The free demo version of EZNEC available from
http://eznec.com can easily answer questions just like
this.



It refuses to calculate SWR due to multiple wires
running so close would create interactions.

Bill

On 12-Dec-2004, "William H. O'Hara, III" wrote:

Roy Lewallen wrote in
:

The free demo version of EZNEC available from
http://eznec.com can easily answer questions just like
this.


It refuses to calculate SWR due to multiple wires
running so close would create interactions.

Bill

Hi Bill,

Not sure about EZNEC Demo, but EZNEC 3.0 models it and gives Source Data (SWR) in the 600 to 1200
ohm range. Maybe you should check your connections and try again. For what it's worth, the pattern
is like most large horizontal loops, except for two large lobes in the direction of the top corners
of the tee.

Ken Fowler

I did quickly in the middle of the night. I will
look it over and see I can find some problem with
the wires. I used EZNEC demo 4.0.

Thanks
Bill

Maybe you should check your connections and try again. For
what it's worth, the pattern is like most large horizontal
loops, except for two large lobes in the direction of the
top corners of the tee.

Ken Fowler