[AMRadio] Radio Noise, BPL?

[Jim Wilhite]

Bill,

While it would be nice to know the cause of the problem, it 
shouldn't be necessary to find the exact problem.  If you have 
traced the noise to the vacant building's power inlet with 
reasonable certainty then I would report it to the utility.

You say that it wipes out the BC band, which is what I would report 
rather than the ham frequencies.  Utilities don't like bad publicity 
over Broadcast frequencies, but sometimes put ham complaints at the 
bottom of the list to work.  I would just tell them it covers up 
your favorite radio stations and can they help.

If they remove power and the problem is still there then you can 
search more, but if it goes away the power company may leave power 
disconnected and notify the owner to fix the problem.  If they 
reconnect power when a new occupant moves in, you may be granted 
access to locate the specific pieces of equipment that is causing 
the problem.

They also may recognize the noise and be able to fix it.  I have had 
that experience before.  No sense in missing out on your favorite 
hobby waiting for someone to move in.

73

Jim/W5JO


----- Original Message ----- 
From: <doxemf at aol.com>
To: <amradio at mailman.qth.net>
Sent: Monday, July 14, 2008 1:59 AM
Subject: Re: [AMRadio] Radio Noise, BPL?


>
> Jim,
>
> This meter/inlet panel is on the outside of the attached office 
> building. The distro panel it feeds is turned off via the main 
> breaker since the building is vacant at this time. The the much 
> larger power drop and panel for the main building where my 
> workshop/storage is located is on the opposite side of the main 
> building and is not a source of noise.
>
> The noise has the fundamental sound of a network cable but without 
> any traffic. Looking at my IF with a scope, the waveform is a flat 
> top positive going pulse with even spaced harmonics maybe, 100kc 
> or less apart. Certainly not phase controller harmonics. I haven't 
> gotten all my gear up and running yet so some of what i'm seeing 
> may be from front end overload.
>  Need to put in some input attenuation to to find the fundamental 
> and actual signal level. It appears to be in or even below
> the broadcast band but the HF receiver only goes down to 1500. At 
> that point the noise level completely buries any broadcast 
> stations. Will try using the portable if it stops raining Monday.
>
> My Spectrum Analyzer, Tek 7L12, was heavily smoke and water 
> damaged recently and I'm a bit lost without it. There is no better 
> tool to locate and identify noise sources. At least one that I can 
> afford.
>
> Don't know, have to get it removed somehow. Would like to get my 
> station back on the air and there is no way with this noise.
> It is way outside
> of a permissible radiation level whatever it is.
>
> Will update when and if the problem goes away.
>
> Thanks !
> Bill, KB3DKS