[Elecraft] KX3 & Chasing local HF noise sources

[Jerome Sodus]

Mike W0MU gave a good beginning, only there is more to the story.

(I gave a class on RFI this past February to our club, so the topic is still
fresh in my mind.)

There may be devices in your house or on your grounds that are
battery-operated, run continuously and may emit RFI.

The batteries must be removed to stop that equipment from operating.

BTW, I wish I could figure out an easy way to reply to a posting here; I
know I must be doing this the hard way.

73 Jerry KM3K

 

Message: 19

Date: Thu, 01 May 2014 23:05:20 -0600

From: W0MU Mike Fatchett <w0mu at w0mu.com>

To: elecraft at mailman.qth.net

Subject: Re: [Elecraft] KX3 & Chasing local HF noise sources

Message-ID: <53632790.4080201 at w0mu.com>

Content-Type: text/plain; charset=ISO-8859-1; format=flowed

 

Run the KX3 on battery and turn off your house mains and see if the 

noise goes away.  If not you know to start looking elsewhere.  You might 

also try the RFI reflector.

 

Mike W0MU

 

On 5/1/2014 10:47 PM, Niel Skousen wrote:

> Good Evening All,

> 

> Questions and Advice sought,  i will report back on results...

> (cross posted to qrp-l, elecraft, and kx3)

> 

> I live in a rural area, which should be very low noise.   i put up a OCFD
(88:44) this afternoon, and tonite wandered on to 80m to listen and check
the antenna.   I had 20db over noise everywhere.   40m was showing S4 noise,
and I could only copy about 4 or 5 stations above the noise on 40m (yep, NR
and NB both on, 400hz wide).

> 

> nearest neighbor is 1/4mi away, and I'm the last one on a rural overhead
power line.

> 

> So,  Given a KX3 and internal batteries, my first thought is to build a
small multi-turn electrostatically shielded loop (1ft dia, 3-5 turn in a
copper pipe, 1" gap at top) and see if I can localize any local noise
sources.

> 

> my office and computers are prime targets of course...

> 

> Is this overkill ?

> Recommendations for a better small / near-field noise pickup ?

> Any other advice for first steps ?

> Anyone else chased noise sources with their KX3 ?   How did it work, what
antenna did you use ?

> Other suggestions / recommendations ?

> 

> TIA, 73

> Niel

> WA7SSA