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Power line noise tracked down on Feb 14th, 2013 to Duke Energy pole number 196 333 or adjacent pole.

(Update : The noise disappeared the week of June 24th and it likely disappeared due to the storm we had on June 25th, 2013, and it reappeared on Wednesday July 17th). Below is a scope capture of AM car radio audio interference on 1710 khz the evening of July 17th at the back of the parking lot of Paws and Play. Note : the frequency of the interference is 132.716msec/16 = 120.6 Hz which again confirms arcing every half cycle of the sine wave.

Youtube Video Recording links

Kenwood TS-180s recording : http://www.youtube.com/watch?v=u2Hc4d0blmI

DX440 recording : http://www.youtube.com/watch?v=7iLjF3zCG4M

Direction finding video : http://www.youtube.com/watch?v=N_xea3Bq0dg

Parabolic Ultrasound unit recording (4/4/2013) : http://youtu.be/B4qw0anjnPM

DX440 recording (6/19/13) at 7:43am (before replacement of insulators) : http://youtu.be/x1Qkdqw5tjA:

Note : Replacement of insulators had no impact on the amplitude of the received noise

Scope screen captures of received audio using various receivers at various locations on Feb 20, 2013 (note main spikes at 120 hertz).

DX-440 audio recording using laptop and scope capture software (frequency 1880 khz AM) 1.07 miles from suspect pole using pennant RX antenna.

Note : the noise bursts are at a frequency of 120 hertz (Example : 1/((50ms - 9ms)/5) = 122 hertz

DX-440 audio recording (June 19, 2013 at 12:47pm after replacement of insulators)

Note : Replacement of insulators had no impact on the amplitude of the received noise

Using laptop and scope capture software (frequency 1880 khz AM) 1.07 miles from suspect pole using pennant RX antenna.

Note : the noise bursts are still at a frequency of 120 hertz (Example : 1/((30ms - 5ms)/3) = 120 hertz).

Car radio audio recording using laptop and scope capture software (frequency 1710 khz AM) 175 feet from suspect pole.

Note : the noise bursts are at a frequency of 120 hertz (Example : 1/((58ms - 1ms)/7) = 123 hertz).

Duke Energy RFI Van (directional antenna through roof, ICOM IC-R8500 receiver, also equipped with Radar Engineering model 250 parabolic ultrasound unit)

WD8DSB direction finding equipment : 136 MHZ AM receiver, Cushcraft 4 element beam (tuned for 136 MHZ using alligator clips to extend elements), and 20 dB attenuator.

Website created and maintained by Don Kirk (WD8DSB), 01/01/2013