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Re: [RFI] Topband: Tecsun 660

To: Michael C Martin <mike@rfiservices.com>, "donovanf@starpower.net" <donovanf@starpower.net>, "topband@contesting.com" <topband@contesting.com>, "rfi@contesting.com" <rfi@contesting.com>
Subject: Re: [RFI] Topband: Tecsun 660
From: "Hare, Ed W1RFI" <w1rfi@arrl.org>
Date: Tue, 8 Mar 2016 21:19:47 +0000
List-post: <rfi@contesting.com">mailto:rfi@contesting.com>
I can't imagine this reliably working well. If noise gets onto long, overhead 
power lines, it will radiate for a long distance. The noise radiated by lines 
closer to the shack than the actual source will often skew off the apparent 
azimuth angle, even if beam nulls and bisecting the angles are used to get a 
bearing, it is going to thrown off to one degree of another by nearby 
radiation, re-radiation and scatterers.  The technique described will give a 
better heading most of the time than trying to use the mail lobe of a 3-element 
Yagi on HF, but I really wouldn't trust it to accurately pinpoint the pole. 

If hams report poles needing fixing and the utility does a truck roll or two to 
fix them, it will hard to get them to do another one, so don't be complacent; 
go out into the field with a VHF Yagi and receiver and either use 
signature-analysis techniques or trace that noise all the way from your house 
to the actual source.  If you wear out your welcome with the power company by 
being wrong, it will be hard to get a new welcome.

Ed Hare, W1RFI



-----Original Message-----
From: RFI [mailto:rfi-bounces@contesting.com] On Behalf Of Michael C Martin
Sent: Tuesday, February 16, 2016 8:53 PM
To: donovanf@starpower.net; topband@contesting.com; rfi@contesting.com
Subject: Re: [RFI] Topband: Tecsun 660

If Stan's friend is that lucky he should attend the casino with me.

Sent with AquaMail for Android
http://www.aqua-mail.com


On February 16, 2016 4:25:01 PM donovanf@starpower.net wrote:

> Hi Stan,
>
>
> There are countless thousands of poles within five miles of my QTH, 
> his method could not possibly work here. If I tried, I would lose my 
> excellent reputation with my power company RFI crew.
>
>
>
> I prefer to leave my shack and verify the pole rather than guessing 
> which one it might be. Its not difficult and a little exercise is a 
> good thing!
>
>
> tks
>
>
> 73
> Frank
> W3LPL
>
> ----- Original Message -----
>
> From: "Stan Stockton" <wa5rtg@gmail.com>
> To: donovanf@starpower.net
> Cc: "Top Band Contesting" <topband@contesting.com>, rfi@contesting.com
> Sent: Tuesday, February 16, 2016 5:19:55 PM
> Subject: Re: Topband: Tecsun 660
>
> Frank,
>
> I have a friend who has used the RF Gain control as needed, balanced 
> antenna and accurate, equal measurement of the strength of the noise 
> off center by an equal number of degrees CW and CCW from the actual 
> direction to determine with great accuracy the direction of the noise. 
> Then plotting a line using GPS mapping has actually called the power 
> company telling them the exact pole where the problem is located without ever 
> leaving his shack.
> He said he could have given them the pole number where the line went 
> right through the pole on the map except for the fact that they had 
> blacked out the number like they do on license plates. The address had to 
> suffice.
> Pretty neat!
>
> 73... Stan, K5GO
>
>> On Feb 16, 2016, at 9:18 AM, donovanf@starpower.net wrote:
>>
>> Hi Jeff,
>>
>>
>> My consistent practice is to identify the highest frequency where I 
>> can hear the RFI in my shack. I then use my directive antennas to 
>> determine the bearing on which I should search. I can consistently 
>> determine azimuth within better than ten degree accuracy on any band. 
>> I begin my search on that frequency with the PL-660 in wide band AM 
>> mode, walking or driving along the line of bearing.
>>
>>
>> The PL-660 has a built in loopstick antenna very useful for direction 
>> finding but active only in the AM broadcast band
>> (540-1700 kHz). Above 1700 kHz it uses a short retractable whip 
>> antenna (slightly useful for direction finding) or an external 
>> antenna.
>>
>>
>> Usually (but definitely not always) the RFI can be heard on higher 
>> frequencies as you get closer to the source, in many cases up the the 
>> aircraft band or all the way up to 450 MHz (on a different receiver). 
>> So far my most distant RFI was AC power line RFI very strong at my 
>> QTH that originates four miles away, It was a serious visible arc on 
>> a 34 kV subtransmission line (not a local
>> 13 kV distribution line). The power company was very motivated to 
>> repair it quickly.
>>
>>
>> This recent RFI was very different than anything I've ever 
>> experienced, I could hear the RFI only on the 160 meter band (about 
>> 1500- 2000 kHz) It sounded like white noise with no audible 60 Hz (or 
>> 60 Hz harmonic) component, The only way I could locate it was by 
>> using the PL-660 S-meter with the PL-660 in wideband AM mode. It 
>> turned out to be a malfunctioning Travellers' Information Station 
>> transmitter at 1700 kHz. Local hams have an excellent relationship 
>> with the county Office of Emergency Management that operates the 
>> transmitter and they turned it off within hours of being notified of 
>> the problem.
>>
>>
>> This is only the second RFI that I've experienced that affects only 
>> 160 meters. The first one was very intense RFI that sounded exactly 
>> like classic AC power line RFI but strangely it affected only 160 
>> meters and the AM broadcast band.
>> It turned out to be a malfunctioning electric fence charger one mile 
>> away that was stuck continuously on, not pulsing.
>> Unfortunately the landowner (an electrician!) was very belligerent 
>> about refusing to replace his fence charger, but some aggressive 
>> "social engineering" motivated him to change his behavior.
>>
>>
>> 73
>> Frank
>> W3LPL
>>
>>
>> ----- Original Message -----
>>
>> From: K1ZM@aol.com
>> To: donovanf@starpower.net
>> Sent: Tuesday, February 16, 2016 10:08:22 AM
>> Subject: Tecsun 660
>>
>> Hi Frank
>>
>> I read your emails on your RFI search.
>>
>> Youmay have mentioned it, but what FREQ BAND did you use on the 
>> TECSUN in your search for the source?
>>
>> Was it the AIRCRAFT BAND on FM?
>>
>> The reason I ask is that I have a similar radio - that is very 
>> similar to the radio you used - just made by SONY.
>>
>> I wonder if I could use it like you did? I am 99% sure it has the 
>> aricraft FM band in it.
>>
>> Pls let me know when you can.
>>
>> Tks
>>
>> 73 JEFF</HTML>
>>
>> _________________
>> Topband Reflector Archives - http://www.contesting.com/_topband
>
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