[PPRAANet] Power Line Noise in COS

[WA6IFI]

Paul, great story. About 20 years ago, when I was working for HP/Agilent, we made a 4918A Ultrasonic Leak Detector. It also used a parabolic dish and a 40KHz detector and down converter system. It was used to detect pin hole leaks in pressurized telephone cable.  Those were the days. 

Dave Novotny, WA6IFI
Chairman, Cheyenne Mountain Repeater Group 
719-439-9077

> On Mar 4, 2020, at 7:03 AM, Paul Signorelli <w0rw1 at msn.com> wrote:
> 
>    You may recall that i had some power line noise a few years ago when i was operating 2 meters AM.  We had a COS net with a lot of Gonset Communicators on 145.550.
> AM is really susceptible to noise interference. That noise will also mask out weak signals even if you are on FM but you may not notice it.
>   i called my old friend Jerry Forte (CSU, CEO) and he sent out a few guys to see what was causing the noise. i had found a noisy power pole with my AM Receiver and a 4 element beam. It was about 100 yards away. i showed the Linemen the spot and the 'engineer' had an
> Ultrasonic Arc Detector. It had a little parabolic reflector that converted 40 kHz down to a baseband of regular audio frequencies. He confirmed the arcing noise with a little more angular resolution.  One lineman took a bucket truck up the side of the pole and hammered
> in all the ground wire staples and got up to the metal cross arm supports.
> As soon as he hit the cross arm supports the noise stopped. The supports are metal and about 3 feet long and are attached to the pole with big metal screws.  He tightened the screws and the job was over.
>   Years before we had an 8KV insulator crack and they found it and replaced it.
> That is just the history of the noise in my area. Yesterday i was talking to to senior CSU line men who each had their own bucket truck and i told them this story. They were interested in Ham Radio. When i got the the 'Ultrasonic Arc Detector' they had a blank stare. They had no idea what it was or that CSU owns one that they could use on their job.
> i told them they could buy one  from MFJ,
> https://www.mfjenterprises.com/Product.php?productid=MFJ-5008
>   Amazing  !!!
> Paul   w0rw
> 
> 
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