Loop antenna question
 

Time to liven things up in here!

My intuition is that a modest sized, untuned, unamplified loop, fed
with a matching transformer, should be quieter and yield a better S/N
ratio than an amplified loop--even when the amplifier is itself very
'clean'. However, my attempts to build an unamplifed loop that is
quieter than--or even as quiet as--my Wellbrook suggest otherwise. Why
is this? Why doesn't an unamplified loop beat an amplified loop every
time when it comes to S/N ratio, assuming of course that it's large
enough to gather a healthy amount of signal to begin with? I'm
especially puzzled by this in light of the fact that the Wellbrook
appears not to be shielded in any way (or at any rate, that's what I
gather from a previous thread on that topic).

Steve

Loop antenna question
 

"Steve" wrote in message
oups.com...
Time to liven things up in here!

My intuition is that a modest sized, untuned, unamplified loop, fed
with a matching transformer, should be quieter and yield a better S/N
ratio than an amplified loop--even when the amplifier is itself very
'clean'. However, my attempts to build an unamplifed loop that is
quieter than--or even as quiet as--my Wellbrook suggest otherwise. Why
is this? Why doesn't an unamplified loop beat an amplified loop every
time when it comes to S/N ratio, assuming of course that it's large
enough to gather a healthy amount of signal to begin with? I'm
especially puzzled by this in light of the fact that the Wellbrook
appears not to be shielded in any way (or at any rate, that's what I
gather from a previous thread on that topic).

Steve

Hey Steve,

How's that ANC-4 been working with your Wellbrook?

-Brian

Loop antenna question
 

Brian wrote:
"Steve" wrote in message
oups.com...
Time to liven things up in here!

My intuition is that a modest sized, untuned, unamplified loop, fed
with a matching transformer, should be quieter and yield a better S/N
ratio than an amplified loop--even when the amplifier is itself very
'clean'. However, my attempts to build an unamplifed loop that is
quieter than--or even as quiet as--my Wellbrook suggest otherwise. Why
is this? Why doesn't an unamplified loop beat an amplified loop every
time when it comes to S/N ratio, assuming of course that it's large
enough to gather a healthy amount of signal to begin with? I'm
especially puzzled by this in light of the fact that the Wellbrook
appears not to be shielded in any way (or at any rate, that's what I
gather from a previous thread on that topic).

Steve

Hey Steve,

How's that ANC-4 been working with your Wellbrook?

-Brian

Thanks for asking. It's been working really well. I'm using it right
now, in fact. For the past couple of weeks I've also been playing
around with an RF Systems MTA antenna. Phasing it with the Wellbrook is
very effective.

Steve

Loop antenna question
 

In article .com,
"Steve" wrote:

Time to liven things up in here!

My intuition is that a modest sized, untuned, unamplified loop, fed
with a matching transformer, should be quieter and yield a better S/N
ratio than an amplified loop--even when the amplifier is itself very
'clean'. However, my attempts to build an unamplifed loop that is
quieter than--or even as quiet as--my Wellbrook suggest otherwise. Why
is this? Why doesn't an unamplified loop beat an amplified loop every
time when it comes to S/N ratio, assuming of course that it's large
enough to gather a healthy amount of signal to begin with? I'm
especially puzzled by this in light of the fact that the Wellbrook
appears not to be shielded in any way (or at any rate, that's what I
gather from a previous thread on that topic).

How did you come to that intuitive conclusion? Generally an electrically
smaller loop will be less sensitive to electric fields. When you make a
larger loop so you get enough unamplified signal and it becomes
electrically larger then it becomes somewhat sensitive to electric
fields. Electrically large loops can be equally sensitive to electric
and magnetic fields.

Besides size are both loops in the same location? How did you shield
your larger loop?

How do you know that the Wellbrook is not shielded? I would have to
either ask the maker or buy one and take it apart to find out.

--
Telamon
Ventura, California

Loop antenna question
 

Telamon wrote:
In article .com,
"Steve" wrote:

Time to liven things up in here!

My intuition is that a modest sized, untuned, unamplified loop, fed
with a matching transformer, should be quieter and yield a better S/N
ratio than an amplified loop--even when the amplifier is itself very
'clean'. However, my attempts to build an unamplifed loop that is
quieter than--or even as quiet as--my Wellbrook suggest otherwise. Why
is this? Why doesn't an unamplified loop beat an amplified loop every
time when it comes to S/N ratio, assuming of course that it's large
enough to gather a healthy amount of signal to begin with? I'm
especially puzzled by this in light of the fact that the Wellbrook
appears not to be shielded in any way (or at any rate, that's what I
gather from a previous thread on that topic).

How did you come to that intuitive conclusion? Generally an electrically
smaller loop will be less sensitive to electric fields. When you make a
larger loop so you get enough unamplified signal and it becomes
electrically larger then it becomes somewhat sensitive to electric
fields. Electrically large loops can be equally sensitive to electric
and magnetic fields.

That makes sense.


Besides size are both loops in the same location? How did you shield
your larger loop?

Not exactly the same location. Separated by about 20 ft.


How do you know that the Wellbrook is not shielded? I would have to
either ask the maker or buy one and take it apart to find out.

--
Telamon
Ventura, California

I thought someone on here did see one taken apart, but maybe my memory
is playing tricks on me.

Steve

Loop antenna question
 

I remember that Train I was rideing on from boot camp at Fort
Gordon,Georgia,the Train from Augusta,Georgia to
Belleville,Illinois.When the Train pulled into Belleville,in side the
Train Station (I was in the U.S.Army,on me way to Scott Air Force
Base,Illinois,January 1963,Nuclear Nike Missiles) the sound system
inside of the Belleville Train Station (it was about midnight at the
time) was playing,Here We Go Loop The Loop.
cuhulin

Loop antenna question
 

Steve wrote:
Telamon wrote:
In article .com,
"Steve" wrote:

Time to liven things up in here!

My intuition is that a modest sized, untuned, unamplified loop, fed
with a matching transformer, should be quieter and yield a better S/N
ratio than an amplified loop--even when the amplifier is itself very
'clean'. However, my attempts to build an unamplifed loop that is
quieter than--or even as quiet as--my Wellbrook suggest otherwise. Why
is this? Why doesn't an unamplified loop beat an amplified loop every
time when it comes to S/N ratio, assuming of course that it's large
enough to gather a healthy amount of signal to begin with? I'm
especially puzzled by this in light of the fact that the Wellbrook
appears not to be shielded in any way (or at any rate, that's what I
gather from a previous thread on that topic).

How did you come to that intuitive conclusion? Generally an electrically
smaller loop will be less sensitive to electric fields. When you make a
larger loop so you get enough unamplified signal and it becomes
electrically larger then it becomes somewhat sensitive to electric
fields. Electrically large loops can be equally sensitive to electric
and magnetic fields.

That makes sense.


Besides size are both loops in the same location? How did you shield
your larger loop?

Not exactly the same location. Separated by about 20 ft.


How do you know that the Wellbrook is not shielded? I would have to
either ask the maker or buy one and take it apart to find out.

--
Telamon
Ventura, California

I thought someone on here did see one taken apart, but maybe my memory
is playing tricks on me.

Steve

The Wellbrook isn't shielded. You can email them to verify.

Out of curiousity, what kind of matching transformer did you use?

Loop antenna question
 

Here we go loop the loop,,, here we go loop the lyyyy,,,,,,,,
I can'ts reckymember all of the lyrics/words of that damn god auld song.
cuhulin

Loop antenna question
 

Ut Ohhhh,,, Cocoon movie has started on Radio tv now.DAT eeese,,,,
Troops,,, I will be in the area for a while.
cuhulin

Loop antenna question
 

On Dec 6, 1:10 pm, "Steve" wrote:
Time to liven things up in here!

My intuition is that a modest sized, untuned, unamplified loop, fed
with a matching transformer, should be quieter and yield a better S/N
ratio than an amplified loop--even when the amplifier is itself very
'clean'. However, my attempts to build an unamplifed loop that is
quieter than--or even as quiet as--my Wellbrook suggest otherwise. Why
is this? Why doesn't an unamplified loop beat an amplified loop every
time when it comes to S/N ratio, assuming of course that it's large
enough to gather a healthy amount of signal to begin with? I'm
especially puzzled by this in light of the fact that the Wellbrook
appears not to be shielded in any way (or at any rate, that's what I
gather from a previous thread on that topic).

Steve

Steve,

Take a piece of 300 Ohm TV type Twin-Lead that
is positioned on the Wall near the Ceiling as an
Around-the-Room Loop Antenna Element.
[ 8 to 15 Foot Square Room = 32 to 60 Foot Loop ]

TIP - An Out-Side mounted Horizontal Loop Antenna
Element would be better - Space permitting.
[ 15 to 30 Foot Square = 60 to 120 Foot Loop ]
- - - Mounted 8 to 16 Foot above the ground.

Use a 300 Ohm to 75 Ohm TV type Matching
Transformer along with a piece of 75 Ohm Coax
Cable for a feed-in-line to the Radio.

Try the 300 Ohm TV type Twin-Lead in a few
different "Loop" hook-up configurations :
* Twin {Parallel} Loops ~ 40-50 Ft
* Single {Series Dual} Loops ~ 80-100 Ft
* Opposing {L&R} Circular Dipole Arms ~ 80-100 Ft T2T

While it may be eaiser to find a Noise Free Location
for the smaller Wellbrook Loop Antenna Element :
Ensuring that all parts of a larger Loop Antenna
Element are away from sources of Noise may be
more difficult to accomplish within the limited space
that we have to work within most back yards.


iane ~ RHF