[RFI] Position of noise cancel antenna

w4lde w4lde at numail.org
Tue Nov 11 16:42:17 EST 2008

Unfortunately I have had for the past month or so a significant level of 
line noise, power company is working on installing new poles and wire 
and have not completed the task although it looks like there close to 
the finish line.  I have tracked the noise on 144Mhz - AM and also 
331Mhz - AM using a Yaesu VX-5R and a 3-el on 2 meters plus a 7-el cut 
for 440Mhz.  The noise is radiating along the lines and seems to be 
shifting from the point of origin, one day its pole A and then the next 
its pole D..  I attribute this to the work and power imbalances caused 
by the crews.

One day its not there and then the next day its back.  I have been 
keeping a log just in case after their completed and I am not back to 
normal S-0 on 20-meters I can help the service crews locate where the 
installation' crews were and help track it down to a specific area.

In the mean time I have dragged out my old MFJ-1026, put up a 40 meter 
slopper and I am able to reduce the S-9 noise on 40 meters to a S-2 
which meets my needs.  At times the noise has more than one component or 
source so I am constantly needing to look for a new null on the MFJ.

With they correct antenna for a specific freq. the MFJ works quite well.

On 30 meters and 20 meters I can only reduce the noise 4-5 S-units even 
with the noise antenna pre-amp turned on and little to no effect with 
the preamp off.

At present the slopper is running N to S while the main antenna is 
running E to W.  Should I try an redirect the slopper and get it more 
horizontal as in the main antenna?  Would I be better off with more 
vertical component?

Any recommendations as to the type of reference antenna and direction or 
any additional thoughts you might wish to share will be appreciated

73 de Ron W4LDE

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