Tektronix 453 Oscilloscope displaying power line interference

Audio: Sound of 'line noise' noise on IC-756PROII in AM mode

Video: Output of Spectrum Analyzer's video output shown on a Tek453 oscilloscope display:

- Top trace: a 60 Hz sine wave
- Bottom Trace: the 'bouncing' noise pulses

Spec Ana is in Zero Span mode, RBW=30 kHz, tuned to vicinity of 80M ham band (3.5 MHz)

Scene: Scene starts zoomed in on Tek 453 CRT and finishes zommed in on trigger settings

The power pole making this 'noise' was over a mile away near the downtown Allen TX area, across from 201 E. McDermott.

The top trace is from a step-down transformer and shows a 60 Hz reference 'line' signal. The bottom trace shows the RF pulses received on an 80M dipole and displayed using the HP 8557A spectrum analyzer and an oscilloscope. An O-scope was used so a sinewave could be shown along with the RF power line pulse interference and show the phase relationship between the two.

There are two pulses per 1/2 sine or 4 pulses for a complete cycle: one pulse each for arc initiation and arc extinction, giving four pulses per complete 60 Hz cycle.

Update: Radio direction finding (RDF) of the noise source (which was over a mile away):

http://www.youtube.com/watch?v=EUxkXSVCYxg

Actual video of the arcing wire producing the RF noise that was receivable over a mile away:

http://www.youtube.com/watch?v=uhaMJD57QwA

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Category:

Science & Technology

Tags:

• interference
• power line arcing
• power pole
• line noise
• RF Noise
• Tek 453
• Tektronix 453

[VREDFOX]

neat oscilloscope

[uploadJ]

Thanks; I like that old CRT-technology Model 453 scope by Tektronix ...

[desertbard]

Broadband over power line?

[uploadJ]

As it turned out, this was a case of bona fide powerline arcing; I tracked it down and have a vid of the arcing culprit (I think there is a link in the 'more info' section)! There is also a vid of the DF technique I used in where I used a portable shortwave receiver to track down the source which was over a mile away (the reason I tracked it down was 'cause it was tearing up the 80M ham band).

Thanks for the comment BTW.

[uploadJ]

Also - The arc can also be heard in the video of the pole with the arcing; a gap of about an inch across which an arc is struck makes pretty noticable audible buzzing noise and it is easy to locate within 50 feet!

[OrangeZuchinni]

Interesting.

[ugotstyle]

You'll see this at almost any beach. Beach communities often have power line arcing due to the salts in the moist air.

[jstrunck]

Awful!

[aurora990]

I always listen to AM and shortwave radio and there are widespread areas within the city of high radio interference that happens during the summer days. the cause was the 30+ KV power lines that was making a soft buzzing noise where the power lines were hold by the pylons and in some cases can see an electric arc. I bought a radio antenna device that had boosted radio reception and it had eliminated most of the radio noise from arcing power lines.

[envisionelec]

Hmmm, I live on Patterson in Dayton and experienced some pretty terrible AM reception up until a primary wire down the street finally failed, got fixed and the problem completely cleared up. Small world if it was that one. ;)