I noticed this on the Wellbrook website (http://www.wellbrook.uk.com):

The Wellbrook Phased Array is a totally new receiving antenna designed
for optimum MW reception. This Antenna system is only Broadband Phased
Array to offer a uni-directional pattern similar to the Beverage, over
360 degrees with electronic Null Steering. The design is the result of
several years research by Wellbrook's owner and chief design engineer
Andrew H. Ikin. Trials of this new array have been performed in the US
by experienced MW Dxers using the phasing system with high performance
Active Vertical and Active Loop antennas.

These trials demonstrated that the Phased Array equipped with elements
made from ALA 100 Large Aperture triangular Loop Antennas (one of the
world's best active antennas) provided much lower noise and improved
side rejection than an identical array equipped with Active Vertical
antenna elements. This finding was particularly important for DXers
living in urban areas. Moreover, comparative listening tests indicated
that the Phased Array was equally as sensitive and directional as a
1000-1500ft Beverage, with the added advantage of deep null steering!

Phased Array Design: The Phased Array provides a reversible uni-
directional reception pattern similar to a 1 wavelength Beverage with
the added ability for the user to steer up to 50dB nulls around the
back of the array.

The Phased Array consists of a Control Unit and two ALA100 Loop
antennas. Each loop is triangular with just one support pole. The
Phased Array can be expanded to use four ALA100 loop antennas to
provide 360 degree coverage.

The Control Unit combines the output of the two antennas using a
technique known as "Delay line Anti-phasing" i.e. the antennas are
combined in anti-phase plus a Variable Delay-line equal to between 50%
and 100% of the spacing of the antennas. This phasing technique
provides a uni-directional reception pattern over a very wide
bandwidth with only a minor adjustment to the controls.

This has a considerable advantage over the majority other phasing and
noise cancelling systems which require constant adjustment even with
small frequency changes.

PHASED ARRAY KEY FEATURES

Uni-directional pattern similar to the Beverage

Simple to erect (no control Lines)

High Front to Back ratio and side rejection

Up to 50dB null steering

High dynamic range amplifiers IOP3 +42dBm; IOP2 +75dBm

Very low noise ALA100 loop antennas

Lower noise than Active Whip arrays

360° with 4 Loops

12Volt DC power, ideal for Dxpeditions

Only requires 40m antenna spacing

Steve wrote:

I noticed this on the Wellbrook website (http://www.wellbrook.uk.com):

The Wellbrook Phased Array is a totally new receiving antenna designed
for optimum MW reception. This Antenna system is only Broadband Phased
Array to offer a uni-directional pattern similar to the Beverage, over
360 degrees with electronic Null Steering. The design is the result of
several years research by Wellbrook's owner and chief design engineer
Andrew H. Ikin. Trials of this new array have been performed in the US
by experienced MW Dxers using the phasing system with high performance
Active Vertical and Active Loop antennas.

These trials demonstrated that the Phased Array equipped with elements
made from ALA 100 Large Aperture triangular Loop Antennas (one of the
world's best active antennas) provided much lower noise and improved
side rejection than an identical array equipped with Active Vertical
antenna elements. This finding was particularly important for DXers
living in urban areas. Moreover, comparative listening tests indicated
that the Phased Array was equally as sensitive and directional as a
1000-1500ft Beverage, with the added advantage of deep null steering!

Phased Array Design: The Phased Array provides a reversible uni-
directional reception pattern similar to a 1 wavelength Beverage with
the added ability for the user to steer up to 50dB nulls around the
back of the array.

The Phased Array consists of a Control Unit and two ALA100 Loop
antennas. Each loop is triangular with just one support pole. The
Phased Array can be expanded to use four ALA100 loop antennas to
provide 360 degree coverage.

The Control Unit combines the output of the two antennas using a
technique known as "Delay line Anti-phasing" i.e. the antennas are
combined in anti-phase plus a Variable Delay-line equal to between 50%
and 100% of the spacing of the antennas. This phasing technique
provides a uni-directional reception pattern over a very wide
bandwidth with only a minor adjustment to the controls.

This has a considerable advantage over the majority other phasing and
noise cancelling systems which require constant adjustment even with
small frequency changes.

PHASED ARRAY KEY FEATURES

Uni-directional pattern similar to the Beverage

Simple to erect (no control Lines)

High Front to Back ratio and side rejection

Up to 50dB null steering

High dynamic range amplifiers IOP3 +42dBm; IOP2 +75dBm

Very low noise ALA100 loop antennas

Lower noise than Active Whip arrays

360° with 4 Loops

12Volt DC power, ideal for Dxpeditions

Only requires 40m antenna spacing

I use 2 ALA1530s (along with 6 Dymek McKay active whips) in an 8-element phased
array.

One unpleasant fact about phasing with two loops is that you can't get a good null
at broadside, that is, in the area already in the null of the loops.

The reason is that a very slight deviation in the angle of arrival of the unwanted
signal reverses the phase of the signal, and so your phasing is completely wrong
for getting a deep null on that signal.

Paradoxically, the best null comes from pointing both loops at the unwanted signal,
which gives the most stable signal phases ; except that the adjustment has to be
finer and finer the stronger the unwanted signal is, and so a compromise is usually
more workable, pointing the loops a little at the unwanted signal enough to stabilize
the phase, but not so much that the signal strength is raised hugely. The more stable
the direction of arrival (say it's a local), the further to broadside you can put the
unwanted signal.

Anyway, there's trouble eliminating signals at broadside by adjusting the phasing,
with loops. No such problem comes up with whips.

A better deal all around is phasing a loop with a co-located whip, which gives
360 degree coverage with zero antenna spacing.
--


On the internet, nobody knows you're a jerk.

On Aug 14, 10:27 am, Ron Hardin wrote:
Steve wrote:

I noticed this on the Wellbrook website (http://www.wellbrook.uk.com):

The Wellbrook Phased Array is a totally new receiving antenna designed
for optimum MW reception. This Antenna system is only Broadband Phased
Array to offer a uni-directional pattern similar to the Beverage, over
360 degrees with electronic Null Steering. The design is the result of
several years research by Wellbrook's owner and chief design engineer
Andrew H. Ikin. Trials of this new array have been performed in the US
by experienced MW Dxers using the phasing system with high performance
Active Vertical and Active Loop antennas.

These trials demonstrated that the Phased Array equipped with elements
made from ALA 100 Large Aperture triangular Loop Antennas (one of the
world's best active antennas) provided much lower noise and improved
side rejection than an identical array equipped with Active Vertical
antenna elements. This finding was particularly important for DXers
living in urban areas. Moreover, comparative listening tests indicated
that the Phased Array was equally as sensitive and directional as a
1000-1500ft Beverage, with the added advantage of deep null steering!

Phased Array Design: The Phased Array provides a reversible uni-
directional reception pattern similar to a 1 wavelength Beverage with
the added ability for the user to steer up to 50dB nulls around the
back of the array.

The Phased Array consists of a Control Unit and two ALA100 Loop
antennas. Each loop is triangular with just one support pole. The
Phased Array can be expanded to use four ALA100 loop antennas to
provide 360 degree coverage.

The Control Unit combines the output of the two antennas using a
technique known as "Delay line Anti-phasing" i.e. the antennas are
combined in anti-phase plus a Variable Delay-line equal to between 50%
and 100% of the spacing of the antennas. This phasing technique
provides a uni-directional reception pattern over a very wide
bandwidth with only a minor adjustment to the controls.

This has a considerable advantage over the majority other phasing and
noise cancelling systems which require constant adjustment even with
small frequency changes.

PHASED ARRAY KEY FEATURES

Uni-directional pattern similar to the Beverage

Simple to erect (no control Lines)

High Front to Back ratio and side rejection

Up to 50dB null steering

High dynamic range amplifiers IOP3 +42dBm; IOP2 +75dBm

Very low noise ALA100 loop antennas

Lower noise than Active Whip arrays

360° with 4 Loops

12Volt DC power, ideal for Dxpeditions

Only requires 40m antenna spacing

I use 2 ALA1530s (along with 6 Dymek McKay active whips) in an 8-element phased
array.

One unpleasant fact about phasing with two loops is that you can't get a good null
at broadside, that is, in the area already in the null of the loops.

The reason is that a very slight deviation in the angle of arrival of the unwanted
signal reverses the phase of the signal, and so your phasing is completely wrong
for getting a deep null on that signal.

Paradoxically, the best null comes from pointing both loops at the unwanted signal,
which gives the most stable signal phases ; except that the adjustment has to be
finer and finer the stronger the unwanted signal is, and so a compromise is usually
more workable, pointing the loops a little at the unwanted signal enough to stabilize
the phase, but not so much that the signal strength is raised hugely. The more stable
the direction of arrival (say it's a local), the further to broadside you can put the
unwanted signal.

Anyway, there's trouble eliminating signals at broadside by adjusting the phasing,
with loops. No such problem comes up with whips.

A better deal all around is phasing a loop with a co-located whip, which gives
360 degree coverage with zero antenna spacing.
--


On the internet, nobody knows you're a jerk.- Hide quoted text -

- Show quoted text -

I phase my ALA-330S with a PA0RDT Mini-Whip. The mini whip is really
just a noise antenna, but it's a good one.

I have been DXing with one of the trial units for the last few months on
DXpeditions.

The unit was also supplied with "head units" (AVA100) for vertical arrays,
as well as the loop element (ALA100) version.

Overall I found the loops working better, and provided deeper nulls. The
null setting stays steady over nearly the entire MW range-- a big advantage.

I expect to be doing further experimenting with this antenna at the WA coast
again later this month, including trying some alternate loop configurations
and comparisons to BOG (Beverage on ground) antennas.

Guy Atkins KE7MAV
Puyallup, WA


"Steve" wrote in message
oups.com...
I noticed this on the Wellbrook website (http://www.wellbrook.uk.com):

The Wellbrook Phased Array is a totally new receiving antenna designed
for optimum MW reception. This Antenna system is only Broadband Phased
Array to offer a uni-directional pattern similar to the Beverage, over
360 degrees with electronic Null Steering. The design is the result of
several years research by Wellbrook's owner and chief design engineer
Andrew H. Ikin. Trials of this new array have been performed in the US
by experienced MW Dxers using the phasing system with high performance
Active Vertical and Active Loop antennas.

These trials demonstrated that the Phased Array equipped with elements
made from ALA 100 Large Aperture triangular Loop Antennas (one of the
world's best active antennas) provided much lower noise and improved
side rejection than an identical array equipped with Active Vertical
antenna elements. This finding was particularly important for DXers
living in urban areas. Moreover, comparative listening tests indicated
that the Phased Array was equally as sensitive and directional as a
1000-1500ft Beverage, with the added advantage of deep null steering!

Phased Array Design: The Phased Array provides a reversible uni-
directional reception pattern similar to a 1 wavelength Beverage with
the added ability for the user to steer up to 50dB nulls around the
back of the array.

The Phased Array consists of a Control Unit and two ALA100 Loop
antennas. Each loop is triangular with just one support pole. The
Phased Array can be expanded to use four ALA100 loop antennas to
provide 360 degree coverage.

The Control Unit combines the output of the two antennas using a
technique known as "Delay line Anti-phasing" i.e. the antennas are
combined in anti-phase plus a Variable Delay-line equal to between 50%
and 100% of the spacing of the antennas. This phasing technique
provides a uni-directional reception pattern over a very wide
bandwidth with only a minor adjustment to the controls.

This has a considerable advantage over the majority other phasing and
noise cancelling systems which require constant adjustment even with
small frequency changes.

PHASED ARRAY KEY FEATURES

Uni-directional pattern similar to the Beverage

Simple to erect (no control Lines)

High Front to Back ratio and side rejection

Up to 50dB null steering

High dynamic range amplifiers IOP3 +42dBm; IOP2 +75dBm

Very low noise ALA100 loop antennas

Lower noise than Active Whip arrays

360° with 4 Loops

12Volt DC power, ideal for Dxpeditions

Only requires 40m antenna spacing

On Aug 15, 10:34 am, "Guy Atkins" wrote:
I have been DXing with one of the trial units for the last few months on
DXpeditions.

The unit was also supplied with "head units" (AVA100) for vertical arrays,
as well as the loop element (ALA100) version.

Overall I found the loops working better, and provided deeper nulls. The
null setting stays steady over nearly the entire MW range-- a big advantage.

I expect to be doing further experimenting with this antenna at the WA coast
again later this month, including trying some alternate loop configurations
and comparisons to BOG (Beverage on ground) antennas.

Guy Atkins KE7MAV
Puyallup, WA



Any comments on the phasing unit itself? Is it comparable performance-
wise to the units available from MFJ and Timewave or is it a cut
above?

Steve

Overall I found the loops working better, and provided deeper nulls.

The depth of nulls depends on (1) the skill of the operator, since a two-dimensional search
is necessary to find the null; (2) the bandspread of the controls - for a hugely deep null,
you're dealing with fractions of fractions of degrees in steering, and the control can easily
be too clumsy at that fine adjustment; (3) the amount of E-field picked up by the loop, or
H-field picked up by the whip : the ``other'' field is 90 degrees out of phase and cannot be
cancelled if it leaks in. With a skilled operator, (3) is always the limit.

Oh and (4), if it's skywave, the actual angle of arrival varies, and may make nulling
impossible for any phased setup that depends on steering a first-order null onto a target.

--


On the internet, nobody knows you're a jerk.

"Steve" wrote in message
oups.com...
Any comments on the phasing unit itself? Is it comparable performance-
wise to the units available from MFJ and Timewave or is it a cut
above?

Steve

Steve, I've used an MFJ phaser, and a JPS noise canceller/phaser, but not
the Timewave unit. The Wellbrook phasing box is definitely easier to find
the nulls with, compared to phasers I've used before. Most of my experience,
though, is with Beverage antennas; performance of this Wellbrook Array is
pretty darn close! It's VERY nice to have the switchable directionality,
which is like having to opposite antennas in the same physical space. I'll
know more in a week, after I return from a DXpedition with a friend who also
has the same Wellbrook Phased Array. We will be trying some alternate
configurations of loops, and comparing the arrays against BOGs and
Beverages.

Guy

On Aug 14, 5:40 am, Steve wrote:
I noticed this on the Wellbrook website (http://www.wellbrook.uk.com):

The Wellbrook Phased Array is a totally new receiving antenna designed
for optimum MW reception. This Antenna system is only Broadband Phased
Array to offer a uni-directional pattern similar to the Beverage, over
360 degrees with electronic Null Steering. The design is the result of
several years research by Wellbrook's owner and chief design engineer
Andrew H. Ikin. Trials of this new array have been performed in the US
by experienced MW Dxers using the phasing system with high performance
Active Vertical and Active Loop antennas.

These trials demonstrated that the Phased Array equipped with elements
made from ALA 100 Large Aperture triangular Loop Antennas (one of the
world's best active antennas) provided much lower noise and improved
side rejection than an identical array equipped with Active Vertical
antenna elements. This finding was particularly important for DXers
living in urban areas. Moreover, comparative listening tests indicated
that the Phased Array was equally as sensitive and directional as a
1000-1500ft Beverage, with the added advantage of deep null steering!

Phased Array Design: The Phased Array provides a reversible uni-
directional reception pattern similar to a 1 wavelength Beverage with
the added ability for the user to steer up to 50dB nulls around the
back of the array.

The Phased Array consists of a Control Unit and two ALA100 Loop
antennas. Each loop is triangular with just one support pole. The
Phased Array can be expanded to use four ALA100 loop antennas to
provide 360 degree coverage.

The Control Unit combines the output of the two antennas using a
technique known as "Delay line Anti-phasing" i.e. the antennas are
combined in anti-phase plus a Variable Delay-line equal to between 50%
and 100% of the spacing of the antennas. This phasing technique
provides a uni-directional reception pattern over a very wide
bandwidth with only a minor adjustment to the controls.

This has a considerable advantage over the majority other phasing and
noise cancelling systems which require constant adjustment even with
small frequency changes.

PHASED ARRAY KEY FEATURES

Uni-directional pattern similar to the Beverage

Simple to erect (no control Lines)

High Front to Back ratio and side rejection

Up to 50dB null steering

High dynamic range amplifiers IOP3 +42dBm; IOP2 +75dBm

Very low noise ALA100 loop antennas

Lower noise than Active Whip arrays

360° with 4 Loops

12Volt DC power, ideal for Dxpeditions

- Only requires 40m antenna spacing

Wow ! - 40 Metres "Spacing" is about 131 Feet
and that is bigger then many Urban Lots. ~ RHF
.
.
.. .