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Tony Giacometti October 11th 07 08:39 PM

Low Noise Receiving antennas
 
Steve wrote:

On Oct 11, 2:37 pm, Tony Giacometti wrote:
Steve wrote:
On Oct 11, 1:38 pm, Tony Giacometti wrote:
I live in a neighborhood that as the years have gone on
has added a number of new homes. This has increased the
electrical "noise" for me where S1 or S2 on 80 meters 6-8 yrs ago
is now S7 to S9. At this point in time I don't have the room for a
K9AY setup. I can only "dream" of a beverage.


I have a Timewave ANC-4 which works very well on 40 meters as I can
null out ALL the "noise".


Not so on 80 meters as it only knocks it down 2 S Units.
At best I have an S-6 noise level.


This leads me to believe that I need a separate sensing antenna for 80
meters. Anyone have any ideas for this problem? Is this thinking
correct?


I have been looking at low noise receiving loops and other low noise
antennas. Wellbrook athttp://www.wellbrook.uk.com/seemsto have some
interresting possibilities, but some of the reviews I have read have
made me hesistant to purchase any of their products.


What I need is some serious input from anyone who has any experience
and knowledge in dealing with low band noise issues.
As I am now space limited due to all the new neighbors any solution
would need to take this into consideration.


TIA


What kind of sense antenna are you currently using? I use an active
whip as a sense antenna (specifically, an H-800 "Skymatch" antenna)
and it enables me to squash *any* noise on 80 meters using my ANC-4.


I use a small dipole like antenna where one half is at 45 degrees the
feed point is a few inches above ground and the other side runs paralle
to ground about 1-2 inches above ground. I think the whole sense antenna
is about 6 ft long and runs in a straight line.

I will look up the H-800 on the web.

Did you try various antennas and configurations before you settled on the
H-800? What made you decide to go with the H-800?

I tried different "antennas" and configurations, for this location this
has worked out the best that I have found. I do realize there could be a
zazillion different antennas and configurations.- Hide quoted text -

- Show quoted text -


I tried lots and lots of different sense antennas and got varying
results. The H-800 gives me the best results from among all the sense
antennas I've tried, though of course this could be a function of the
particular kinds of noise present at my QTH.

I will say this. Because I live in an urban area it's been my aim to
defeat RFI in every way possible. I use one of the Wellbrook loops and
that helps, but nothing has been as big a help as the ANC-4 WHEN
MATCHED with the right sense antenna.

Part of me suspects that the ideal setup, at least for me, would
involve having a couple of different active whips to switch back and
forth between. I think the H-800 does well on 80 meters because it's
quite sensitive there. However, it's quite a bit less sensitive on,
say, 20 meters and I'll bet I'd get better results using a different
active whip, or perhaps a wire, on higher frequencies.



I have never considered an active antenna for the sense antenna.
Maybe that would work here.
I wonder if anyone else is doing the same thing or if you have "found"
something really unique.

Steve October 11th 07 08:49 PM

Low Noise Receiving antennas
 
On Oct 11, 3:39 pm, Tony Giacometti wrote:
Steve wrote:
On Oct 11, 2:37 pm, Tony Giacometti wrote:
Steve wrote:
On Oct 11, 1:38 pm, Tony Giacometti wrote:
I live in a neighborhood that as the years have gone on
has added a number of new homes. This has increased the
electrical "noise" for me where S1 or S2 on 80 meters 6-8 yrs ago
is now S7 to S9. At this point in time I don't have the room for a
K9AY setup. I can only "dream" of a beverage.


I have a Timewave ANC-4 which works very well on 40 meters as I can
null out ALL the "noise".


Not so on 80 meters as it only knocks it down 2 S Units.
At best I have an S-6 noise level.


This leads me to believe that I need a separate sensing antenna for 80
meters. Anyone have any ideas for this problem? Is this thinking
correct?


I have been looking at low noise receiving loops and other low noise
antennas. Wellbrook athttp://www.wellbrook.uk.com/seemstohave some
interresting possibilities, but some of the reviews I have read have
made me hesistant to purchase any of their products.


What I need is some serious input from anyone who has any experience
and knowledge in dealing with low band noise issues.
As I am now space limited due to all the new neighbors any solution
would need to take this into consideration.


TIA


What kind of sense antenna are you currently using? I use an active
whip as a sense antenna (specifically, an H-800 "Skymatch" antenna)
and it enables me to squash *any* noise on 80 meters using my ANC-4.


I use a small dipole like antenna where one half is at 45 degrees the
feed point is a few inches above ground and the other side runs paralle
to ground about 1-2 inches above ground. I think the whole sense antenna
is about 6 ft long and runs in a straight line.


I will look up the H-800 on the web.


Did you try various antennas and configurations before you settled on the
H-800? What made you decide to go with the H-800?


I tried different "antennas" and configurations, for this location this
has worked out the best that I have found. I do realize there could be a
zazillion different antennas and configurations.- Hide quoted text -


- Show quoted text -


I tried lots and lots of different sense antennas and got varying
results. The H-800 gives me the best results from among all the sense
antennas I've tried, though of course this could be a function of the
particular kinds of noise present at my QTH.


I will say this. Because I live in an urban area it's been my aim to
defeat RFI in every way possible. I use one of the Wellbrook loops and
that helps, but nothing has been as big a help as the ANC-4 WHEN
MATCHED with the right sense antenna.


Part of me suspects that the ideal setup, at least for me, would
involve having a couple of different active whips to switch back and
forth between. I think the H-800 does well on 80 meters because it's
quite sensitive there. However, it's quite a bit less sensitive on,
say, 20 meters and I'll bet I'd get better results using a different
active whip, or perhaps a wire, on higher frequencies.


I have never considered an active antenna for the sense antenna.
Maybe that would work here.
I wonder if anyone else is doing the same thing or if you have "found"
something really unique.- Hide quoted text -

- Show quoted text -


I know at least one other person who does it. He uses one of the McKay-
Dymek whips. I tried the H-800 simply because I already had it laying
around. I couldn't quite see buying an H-800 just for use as a sense
antenna, as they're fairly expensive, but I've seen them go on ebay
for not too much.

Active whips can be real noise magnets. A huge disadvantage if you're
using one as your receive antenna, but a big plus if noise is what you
want it to hear!


Tony Giacometti October 11th 07 09:22 PM

Low Noise Receiving antennas
 
Steve wrote:

On Oct 11, 3:39 pm, Tony Giacometti wrote:
Steve wrote:
On Oct 11, 2:37 pm, Tony Giacometti wrote:
Steve wrote:
On Oct 11, 1:38 pm, Tony Giacometti
wrote:
I live in a neighborhood that as the years have gone on
has added a number of new homes. This has increased the
electrical "noise" for me where S1 or S2 on 80 meters 6-8 yrs ago
is now S7 to S9. At this point in time I don't have the room for a
K9AY setup. I can only "dream" of a beverage.


I have a Timewave ANC-4 which works very well on 40 meters as I can
null out ALL the "noise".


Not so on 80 meters as it only knocks it down 2 S Units.
At best I have an S-6 noise level.


This leads me to believe that I need a separate sensing antenna for
80 meters. Anyone have any ideas for this problem? Is this thinking
correct?


I have been looking at low noise receiving loops and other low
noise
antennas. Wellbrook athttp://www.wellbrook.uk.com/seemstohave some
interresting possibilities, but some of the reviews I have read
have made me hesistant to purchase any of their products.


What I need is some serious input from anyone who has any
experience and knowledge in dealing with low band noise issues.
As I am now space limited due to all the new neighbors any solution
would need to take this into consideration.


TIA


What kind of sense antenna are you currently using? I use an active
whip as a sense antenna (specifically, an H-800 "Skymatch" antenna)
and it enables me to squash *any* noise on 80 meters using my ANC-4.


I use a small dipole like antenna where one half is at 45 degrees the
feed point is a few inches above ground and the other side runs
paralle to ground about 1-2 inches above ground. I think the whole
sense antenna is about 6 ft long and runs in a straight line.


I will look up the H-800 on the web.


Did you try various antennas and configurations before you settled on
the H-800? What made you decide to go with the H-800?


I tried different "antennas" and configurations, for this location
this has worked out the best that I have found. I do realize there
could be a zazillion different antennas and configurations.- Hide
quoted text -


- Show quoted text -


I tried lots and lots of different sense antennas and got varying
results. The H-800 gives me the best results from among all the sense
antennas I've tried, though of course this could be a function of the
particular kinds of noise present at my QTH.


I will say this. Because I live in an urban area it's been my aim to
defeat RFI in every way possible. I use one of the Wellbrook loops and
that helps, but nothing has been as big a help as the ANC-4 WHEN
MATCHED with the right sense antenna.


Part of me suspects that the ideal setup, at least for me, would
involve having a couple of different active whips to switch back and
forth between. I think the H-800 does well on 80 meters because it's
quite sensitive there. However, it's quite a bit less sensitive on,
say, 20 meters and I'll bet I'd get better results using a different
active whip, or perhaps a wire, on higher frequencies.


I have never considered an active antenna for the sense antenna.
Maybe that would work here.
I wonder if anyone else is doing the same thing or if you have "found"
something really unique.- Hide quoted text -

- Show quoted text -


I know at least one other person who does it. He uses one of the McKay-
Dymek whips. I tried the H-800 simply because I already had it laying
around. I couldn't quite see buying an H-800 just for use as a sense
antenna, as they're fairly expensive, but I've seen them go on ebay
for not too much.

Active whips can be real noise magnets. A huge disadvantage if you're
using one as your receive antenna, but a big plus if noise is what you
want it to hear!



But what you are saying is when you use the active antenna with the ANC-4
it works very well for cancelling out the noise.

[email protected] October 11th 07 09:46 PM

Low Noise Receiving antennas
 
On Oct 11, 10:38 am, Tony Giacometti wrote:
I live in a neighborhood that as the years have gone on
has added a number of new homes. This has increased the
electrical "noise" for me where S1 or S2 on 80 meters 6-8 yrs ago
is now S7 to S9. At this point in time I don't have the room for a K9AY
setup. I can only "dream" of a beverage.

I have a Timewave ANC-4 which works very well on 40 meters as I can null out
ALL the "noise".

Not so on 80 meters as it only knocks it down 2 S Units.
At best I have an S-6 noise level.

This leads me to believe that I need a separate sensing antenna for 80
meters. Anyone have any ideas for this problem? Is this thinking correct?

I have been looking at low noise receiving loops and other low noise
antennas. Wellbrook athttp://www.wellbrook.uk.com/seems to have some
interresting possibilities, but some of the reviews I have read have made me
hesistant to purchase any of their products.

What I need is some serious input from anyone who has any experience and
knowledge in dealing with low band noise issues.
As I am now space limited due to all the new neighbors any solution would
need to take this into consideration.

TIA


Hi, Tony.
Several years ago I decided to put my ham radio station back on the
air. The tallest trees on my property here in Central Oregon are
junipers, about 35 feet tall. I managed to get the ends of a 40 meter
dipole up towards the top of the trees. It was fed with coax and a
balun. Petty noisy.

Later, I decided to try the old tried and true folded dipole using 300
ohm TV twinlead and an antenna tuner. This time I was able to get a 75
meter antenna up into the junipers. When I connected the antenna/tuner
the receiver, there was no noise. I actually went outside and checked
for something shorted. Then I checked the antenna for continuity with
an ohm meter. All was ok. This was mid-day and there were no stations
on 75 m. I tuned other bands and there was plenty of activity and very
little noise. Later I began to hear stations from the mid-west on 75
meters.

Bottom line, I think if you can find the room for a folded dipole or
other loop type antenna you will be surprised how much your noise
level goes down.

Best of luck.
Paul, KD7HB


Steve October 11th 07 11:05 PM

Low Noise Receiving antennas
 
On Oct 11, 4:22 pm, Tony Giacometti wrote:
Steve wrote:
On Oct 11, 3:39 pm, Tony Giacometti wrote:
Steve wrote:
On Oct 11, 2:37 pm, Tony Giacometti wrote:
Steve wrote:
On Oct 11, 1:38 pm, Tony Giacometti
wrote:
I live in a neighborhood that as the years have gone on
has added a number of new homes. This has increased the
electrical "noise" for me where S1 or S2 on 80 meters 6-8 yrs ago
is now S7 to S9. At this point in time I don't have the room for a
K9AY setup. I can only "dream" of a beverage.


I have a Timewave ANC-4 which works very well on 40 meters as I can
null out ALL the "noise".


Not so on 80 meters as it only knocks it down 2 S Units.
At best I have an S-6 noise level.


This leads me to believe that I need a separate sensing antenna for
80 meters. Anyone have any ideas for this problem? Is this thinking
correct?


I have been looking at low noise receiving loops and other low
noise
antennas. Wellbrook athttp://www.wellbrook.uk.com/seemstohavesome
interresting possibilities, but some of the reviews I have read
have made me hesistant to purchase any of their products.


What I need is some serious input from anyone who has any
experience and knowledge in dealing with low band noise issues.
As I am now space limited due to all the new neighbors any solution
would need to take this into consideration.


TIA


What kind of sense antenna are you currently using? I use an active
whip as a sense antenna (specifically, an H-800 "Skymatch" antenna)
and it enables me to squash *any* noise on 80 meters using my ANC-4.


I use a small dipole like antenna where one half is at 45 degrees the
feed point is a few inches above ground and the other side runs
paralle to ground about 1-2 inches above ground. I think the whole
sense antenna is about 6 ft long and runs in a straight line.


I will look up the H-800 on the web.


Did you try various antennas and configurations before you settled on
the H-800? What made you decide to go with the H-800?


I tried different "antennas" and configurations, for this location
this has worked out the best that I have found. I do realize there
could be a zazillion different antennas and configurations.- Hide
quoted text -


- Show quoted text -


I tried lots and lots of different sense antennas and got varying
results. The H-800 gives me the best results from among all the sense
antennas I've tried, though of course this could be a function of the
particular kinds of noise present at my QTH.


I will say this. Because I live in an urban area it's been my aim to
defeat RFI in every way possible. I use one of the Wellbrook loops and
that helps, but nothing has been as big a help as the ANC-4 WHEN
MATCHED with the right sense antenna.


Part of me suspects that the ideal setup, at least for me, would
involve having a couple of different active whips to switch back and
forth between. I think the H-800 does well on 80 meters because it's
quite sensitive there. However, it's quite a bit less sensitive on,
say, 20 meters and I'll bet I'd get better results using a different
active whip, or perhaps a wire, on higher frequencies.


I have never considered an active antenna for the sense antenna.
Maybe that would work here.
I wonder if anyone else is doing the same thing or if you have "found"
something really unique.- Hide quoted text -


- Show quoted text -


I know at least one other person who does it. He uses one of the McKay-
Dymek whips. I tried the H-800 simply because I already had it laying
around. I couldn't quite see buying an H-800 just for use as a sense
antenna, as they're fairly expensive, but I've seen them go on ebay
for not too much.


Active whips can be real noise magnets. A huge disadvantage if you're
using one as your receive antenna, but a big plus if noise is what you
want it to hear!


But what you are saying is when you use the active antenna with the ANC-4
it works very well for cancelling out the noise.- Hide quoted text -

- Show quoted text -


Right. The whip is just a noise antenna in my setup.


JIMMIE October 12th 07 11:45 PM

Low Noise Receiving antennas
 
On Oct 11, 1:38 pm, Tony Giacometti wrote:
I live in a neighborhood that as the years have gone on
has added a number of new homes. This has increased the
electrical "noise" for me where S1 or S2 on 80 meters 6-8 yrs ago
is now S7 to S9. At this point in time I don't have the room for a K9AY
setup. I can only "dream" of a beverage.

I have a Timewave ANC-4 which works very well on 40 meters as I can null out
ALL the "noise".

Not so on 80 meters as it only knocks it down 2 S Units.
At best I have an S-6 noise level.

This leads me to believe that I need a separate sensing antenna for 80
meters. Anyone have any ideas for this problem? Is this thinking correct?

I have been looking at low noise receiving loops and other low noise
antennas. Wellbrook athttp://www.wellbrook.uk.com/seems to have some
interresting possibilities, but some of the reviews I have read have made me
hesistant to purchase any of their products.

What I need is some serious input from anyone who has any experience and
knowledge in dealing with low band noise issues.
As I am now space limited due to all the new neighbors any solution would
need to take this into consideration.

TIA


Just out of curiosity, have you tried locating the noise source. I had
the same experience you are having more or less.
I had been away from ham radio for a couple of years and when I fired
it all up again HF was really noisy so I ran the radio off of battery
while I shut down power to my house. I found the source of the noise
was the display on my microwave oven.
Short term solution was keeping the microwave unplugged until needed.
Long term solution was replacing the microwave. I did this when i
found a better one at Goodwill for less than $20. Also check for RF on
the coax during transmit. During rx this means the antenna is also
picking up signals from the shield which may be in close proximity to
noise generators.


Jimmie


Tony Giacometti October 13th 07 07:03 AM

Low Noise Receiving antennas
 
JIMMIE wrote:

On Oct 11, 1:38 pm, Tony Giacometti wrote:
I live in a neighborhood that as the years have gone on
has added a number of new homes. This has increased the
electrical "noise" for me where S1 or S2 on 80 meters 6-8 yrs ago
is now S7 to S9. At this point in time I don't have the room for a K9AY
setup. I can only "dream" of a beverage.

I have a Timewave ANC-4 which works very well on 40 meters as I can null
out ALL the "noise".

Not so on 80 meters as it only knocks it down 2 S Units.
At best I have an S-6 noise level.

This leads me to believe that I need a separate sensing antenna for 80
meters. Anyone have any ideas for this problem? Is this thinking correct?

I have been looking at low noise receiving loops and other low noise
antennas. Wellbrook athttp://www.wellbrook.uk.com/seems to have some
interresting possibilities, but some of the reviews I have read have made
me hesistant to purchase any of their products.

What I need is some serious input from anyone who has any experience and
knowledge in dealing with low band noise issues.
As I am now space limited due to all the new neighbors any solution would
need to take this into consideration.

TIA


Just out of curiosity, have you tried locating the noise source. I had
the same experience you are having more or less.
I had been away from ham radio for a couple of years and when I fired
it all up again HF was really noisy so I ran the radio off of battery
while I shut down power to my house. I found the source of the noise
was the display on my microwave oven.
Short term solution was keeping the microwave unplugged until needed.
Long term solution was replacing the microwave. I did this when i
found a better one at Goodwill for less than $20. Also check for RF on
the coax during transmit. During rx this means the antenna is also
picking up signals from the shield which may be in close proximity to
noise generators.


Jimmie



I did a good assessment of the noise being heard here.
I found an electric razor charger that was some of the problem and
a computer printer was another I found.
So my home is quite clean unless something else has popped up which I don't
know about and can't locate.

I test with power on and power off. Right now theres very little difference
if any between the two.

I would think its coming from someplace else, but until I can come up with
the exact location I need to decide on a solution thats effective.

pa3abk October 14th 07 12:41 AM

Low Noise Receiving antennas
 
On Fri, 12 Oct 2007 20:03:08 -1000, Tony Giacometti
wrote:

JIMMIE wrote:

On Oct 11, 1:38 pm, Tony Giacometti wrote:
I live in a neighborhood that as the years have gone on
has added a number of new homes. This has increased the
electrical "noise" for me where S1 or S2 on 80 meters 6-8 yrs ago
is now S7 to S9. At this point in time I don't have the room for a K9AY
setup. I can only "dream" of a beverage.

I have a Timewave ANC-4 which works very well on 40 meters as I can null
out ALL the "noise".

Not so on 80 meters as it only knocks it down 2 S Units.
At best I have an S-6 noise level.

This leads me to believe that I need a separate sensing antenna for 80
meters. Anyone have any ideas for this problem? Is this thinking correct?

I have been looking at low noise receiving loops and other low noise
antennas. Wellbrook athttp://www.wellbrook.uk.com/seems to have some
interresting possibilities, but some of the reviews I have read have made
me hesistant to purchase any of their products.

What I need is some serious input from anyone who has any experience and
knowledge in dealing with low band noise issues.
As I am now space limited due to all the new neighbors any solution would
need to take this into consideration.

TIA


Just out of curiosity, have you tried locating the noise source. I had
the same experience you are having more or less.
I had been away from ham radio for a couple of years and when I fired
it all up again HF was really noisy so I ran the radio off of battery
while I shut down power to my house. I found the source of the noise
was the display on my microwave oven.
Short term solution was keeping the microwave unplugged until needed.
Long term solution was replacing the microwave. I did this when i
found a better one at Goodwill for less than $20. Also check for RF on
the coax during transmit. During rx this means the antenna is also
picking up signals from the shield which may be in close proximity to
noise generators.


Jimmie



I did a good assessment of the noise being heard here.
I found an electric razor charger that was some of the problem and
a computer printer was another I found.
So my home is quite clean unless something else has popped up which I don't
know about and can't locate.

I test with power on and power off. Right now theres very little difference
if any between the two.

I would think its coming from someplace else, but until I can come up with
the exact location I need to decide on a solution thats effective.

Understand your problem. In the Netherlands we live rather dense to
each other. Consequently when you are a ham and try to receive
something you are confronted with a blanket of man-made noise from
various sources. Mainly they are coming from switched power supplies
in some kind. It's almost impossible to adress all neighbours and
de-noise the equipment. In NL the responsible salesman should remove
these kind of QRM, you will imagine that it will cost a lot of effort
convince him that his product is causing the problem. To get around,
you can sample the noise, reverse it and add it to your antenna
signal. The QRM is simply nulled out. The earlier mentioned ANC-4 is
doing that, however I understood it's not capable to to do the job
very well. Same goes for the MFJ-1025.
Have a look at the page of pa0sim
http://www.pa0sim.nl/Phaser%2080%20-%2010%20meters.htm
Don't worry it's in English and it gives you some ideas how you can
tackle the noise/qrm problem.
If have your QRM sensor is correctly placed for picking up the "noise"
and feedback it, it should do the trick. Alternatively, for those who
have not the man made noise problem, you can null-out a short skip
station in favour of that DX station you would like to work.
Jan/pa3abk

John, N9JG October 14th 07 01:48 AM

Low Noise Receiving antennas
 
If you don't mind spending the bucks, you might want to investigate DXengineering's Noise Canceling Controller. See
http://www.dxengineering.com/Products.asp?ID={6F07CEB4-27D0-4664-A2AA-352A69ED88CD}&SecID=114&DeptID=12

"pa3abk" wrote in message ...
On Fri, 12 Oct 2007 20:03:08 -1000, Tony Giacometti
wrote:

JIMMIE wrote:

On Oct 11, 1:38 pm, Tony Giacometti wrote:
I live in a neighborhood that as the years have gone on
has added a number of new homes. This has increased the
electrical "noise" for me where S1 or S2 on 80 meters 6-8 yrs ago
is now S7 to S9. At this point in time I don't have the room for a K9AY
setup. I can only "dream" of a beverage.

I have a Timewave ANC-4 which works very well on 40 meters as I can null
out ALL the "noise".

Not so on 80 meters as it only knocks it down 2 S Units.
At best I have an S-6 noise level.

This leads me to believe that I need a separate sensing antenna for 80
meters. Anyone have any ideas for this problem? Is this thinking correct?

I have been looking at low noise receiving loops and other low noise
antennas. Wellbrook athttp://www.wellbrook.uk.com/seems to have some
interresting possibilities, but some of the reviews I have read have made
me hesistant to purchase any of their products.

What I need is some serious input from anyone who has any experience and
knowledge in dealing with low band noise issues.
As I am now space limited due to all the new neighbors any solution would
need to take this into consideration.

TIA

Just out of curiosity, have you tried locating the noise source. I had
the same experience you are having more or less.
I had been away from ham radio for a couple of years and when I fired
it all up again HF was really noisy so I ran the radio off of battery
while I shut down power to my house. I found the source of the noise
was the display on my microwave oven.
Short term solution was keeping the microwave unplugged until needed.
Long term solution was replacing the microwave. I did this when i
found a better one at Goodwill for less than $20. Also check for RF on
the coax during transmit. During rx this means the antenna is also
picking up signals from the shield which may be in close proximity to
noise generators.


Jimmie



I did a good assessment of the noise being heard here.
I found an electric razor charger that was some of the problem and
a computer printer was another I found.
So my home is quite clean unless something else has popped up which I don't
know about and can't locate.

I test with power on and power off. Right now theres very little difference
if any between the two.

I would think its coming from someplace else, but until I can come up with
the exact location I need to decide on a solution thats effective.

Understand your problem. In the Netherlands we live rather dense to
each other. Consequently when you are a ham and try to receive
something you are confronted with a blanket of man-made noise from
various sources. Mainly they are coming from switched power supplies
in some kind. It's almost impossible to adress all neighbours and
de-noise the equipment. In NL the responsible salesman should remove
these kind of QRM, you will imagine that it will cost a lot of effort
convince him that his product is causing the problem. To get around,
you can sample the noise, reverse it and add it to your antenna
signal. The QRM is simply nulled out. The earlier mentioned ANC-4 is
doing that, however I understood it's not capable to to do the job
very well. Same goes for the MFJ-1025.
Have a look at the page of pa0sim
http://www.pa0sim.nl/Phaser%2080%20-%2010%20meters.htm
Don't worry it's in English and it gives you some ideas how you can
tackle the noise/qrm problem.
If have your QRM sensor is correctly placed for picking up the "noise"
and feedback it, it should do the trick. Alternatively, for those who
have not the man made noise problem, you can null-out a short skip
station in favour of that DX station you would like to work.
Jan/pa3abk


Steve October 14th 07 05:26 AM

Low Noise Receiving antennas
 
On Oct 13, 8:48 pm, "John, N9JG" wrote:
If you don't mind spending the bucks, you might want to investigate DXengineering's Noise Canceling Controller. Seehttp://www.dxengineering.com/Products.asp?ID={6F07CEB4-27D0-4664-A2AA-352A69ED88CD}&SecID=114&DeptID=12




I'd love to hear from someone who's tried this phasing unit. If it's
really light years ahead of the Timewave and MFJ units, I'd say it's
worth the bucks.




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