I have 2 dipoles up at 60+ ft - one set running East-West other North South .. From 2.6 to 5 Megs I have a S-7 Qrn lev at 4 Am .. buy noon I have a 10-20 over QRN Lev .. I live on 10 acres and have turned off main power to house and still have QRN .. so not coming from anything in house .. This one has me stumped .. 6 moths ago my Qrn was a S-2 .. waiting for a G6 radio to try and track this down but does anybody else have any idea's ?
Tnx
Dave N6CO
Hi Dave, N6CO
If you don't live very close to a big city probably there are sparks into one or more high voltage defective insulators carrying AC power to your town and very close to your antennas.
73" de
i8CVS Domenico
----- Original Message ----- From: "Dave Larsen PhD" [email protected] To: [email protected] Sent: Saturday, August 03, 2013 12:23 AM Subject: [amsat-bb] Help with 75 mtr Qrn problem
I have 2 dipoles up at 60+ ft - one set running East-West other North
South .. From 2.6 to 5 Megs I
have a S-7 Qrn lev at 4 Am .. buy noon I have a 10-20 over QRN Lev .. I
live on 10 acres and have
turned off main power to house and still have QRN .. so not coming from
anything in house .. This one
has me stumped .. 6 moths ago my Qrn was a S-2 .. waiting for a G6 radio
to try and track this down
but does anybody else have any idea's ?
Tnx
Dave N6CO _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Not that uncommon this time of the year! Especially on 160-meters and 80/75-meters, slightly less on 40-meters, the QRN level can be pretty horrid! Much of the noise is caused by lightning that can be hundreds of miles away. Glen, K9STH
Website: http://k9sth.com
________________________________ From: Dave Larsen PhD [email protected] To: [email protected] Sent: Friday, August 2, 2013 5:23 PM Subject: [amsat-bb] Help with 75 mtr Qrn problem
I have 2 dipoles up at 60+ ft - one set running East-West other North South .. From 2.6 to 5 Megs I have a S-7 Qrn lev at 4 Am .. buy noon I have a 10-20 over QRN Lev .. I live on 10 acres and have turned off main power to house and still have QRN .. so not coming from anything in house .. This one has me stumped .. 6 moths ago my Qrn was a S-2 .. waiting for a G6 radio to try and track this down but does anybody else have any idea's ?
Dave,
I had a similar problem on 80 meters at my QTH. The power company couldn't find it. I finally did. I drove the entire area mobile with my 706, trying different bands. Having 2 meter and 70 cm fox hunt antennas, equipment and attenuators helped me a lot too.
The QRN signal on 80 was very high here, about 40-50 over s9. I finally found it over 6 blocks away. It was a lower 'static' line (neutral) touching a back support line, both ran between the two poles and crossed each other barely touching. The funny thing was, when I measured it the distance between the poles was about a half wave on 80/75. So the 'back guy' was a good half wave antenna on 80. And it was aimed my direction.
My noise would go away when wet or damp and would get stronger when the sun came up and warmed everything and evaporated the moisture.
Keep in mind, generally the noise won't be heard on the higher bands (430 mhz) unless you are less than a couple hundred feet away from the source. You can hear 80 meter noise from power lines over a half mile away. The closer you get to electrical noise, the higher in frequency you can 'usually' hear it.
Once you find it, insist the power company see the before and after on your equipment. My contact here didn't believe that I could hear the noise that far away.
Ernie W8EH
On 8/2/2013 6:23 PM, Dave Larsen PhD wrote:
I have 2 dipoles up at 60+ ft - one set running East-West other North South .. From 2.6 to 5 Megs I have a S-7 Qrn lev at 4 Am .. buy noon I have a 10-20 over QRN Lev .. I live on 10 acres and have turned off main power to house and still have QRN .. so not coming from anything in house .. This one has me stumped .. 6 moths ago my Qrn was a S-2 .. waiting for a G6 radio to try and track this down but does anybody else have any idea's ?
Tnx
Dave N6CO _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Hi Ernie, W8EH
I agree with your diagnosys and this is why I writes to Dave N6CO the following information.
"To find out from where the noise come out you need a MFJ-852 Meter A/C Line Noise Meter visible in the following internet address:
http://www.mfjenterprises.com/Product.php?productid=MFJ-852
This instrument is currently used by the Electricity Power Companies in England."
73" de
i8CVS Domenico
----- Original Message ----- From: "Ernie" [email protected] To: "Dave Larsen PhD" [email protected] Cc: [email protected] Sent: Saturday, August 03, 2013 4:52 PM Subject: [amsat-bb] Re: Help with 75 mtr Qrn problem
Dave,
I had a similar problem on 80 meters at my QTH. The power company couldn't find it. I finally did. I drove the entire area mobile with my 706, trying different bands. Having 2 meter and 70 cm fox hunt antennas, equipment and attenuators helped me a lot too.
The QRN signal on 80 was very high here, about 40-50 over s9. I finally found it over 6 blocks away. It was a lower 'static' line (neutral) touching a back support line, both ran between the two poles and crossed each other barely touching. The funny thing was, when I measured it the distance between the poles was about a half wave on 80/75. So the 'back guy' was a good half wave antenna on 80. And it was aimed my direction.
My noise would go away when wet or damp and would get stronger when the sun came up and warmed everything and evaporated the moisture.
Keep in mind, generally the noise won't be heard on the higher bands (430 mhz) unless you are less than a couple hundred feet away from the source. You can hear 80 meter noise from power lines over a half mile away. The closer you get to electrical noise, the higher in frequency you can 'usually' hear it.
Once you find it, insist the power company see the before and after on your equipment. My contact here didn't believe that I could hear the noise that far away.
Ernie W8EH
On 8/2/2013 6:23 PM, Dave Larsen PhD wrote: I have 2 dipoles up at 60+ ft - one set running East-West other North South .. From 2.6 to 5 Megs I have a S-7 Qrn lev at 4 Am .. buy noon I have a 10-20 over QRN Lev .. I live on 10 acres and have turned off main power to house and still have QRN .. so not coming from anything in house .. This one has me stumped .. 6 moths ago my Qrn was a S-2 .. waiting for a G6 radio to try and track this down but does anybody else have any idea's ?
Tnx
Dave N6CO
Had a similar problem once. Got a friend to listen in the shack while I walked around the neighborhood with a sledgehammer. Every time I came to a utility pole i gave it a good whack. One particular pole, when ever I whacked it, there was a blip in the noise. Took the number of the pole, called the utility company and reported seeing sparks.
On 08/02/2013 06:23 PM, Dave Larsen PhD wrote:
I have 2 dipoles up at 60+ ft - one set running East-West other North South .. From 2.6 to 5 Megs I have a S-7 Qrn lev at 4 Am .. buy noon I have a 10-20 over QRN Lev .. I live on 10 acres and have turned off main power to house and still have QRN .. so not coming from anything in house .. This one has me stumped .. 6 moths ago my Qrn was a S-2 .. waiting for a G6 radio to try and track this down but does anybody else have any idea's ?
Tnx
Dave N6CO _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
participants (5)
-
Dave Larsen PhD -
Ernie -
Glen Zook -
Gus -
i8cvs