[Elecraft] K3 Noise Reduction

[Stephen Prior]

I agree, I have used my K3 for almost a year now and I don't recall one
situation where the NR was more effective than the filtering between my
ears, whether on ssb or cw.  As much as I have and continue to enjoy the
radio, I must say much the same about the NB performance.  It was very
enlightening to hook up my FT-817 to the main station antenna the other
night and find that the 817's noise blanker did a far better job than the
K3's in getting rid of the interference from the electric fence which keeps
the foxes away from our chickens!  I don't have any DSP on my K2 so I can
draw no comparison there.

On a really positive note, the one thing which makes the K3 so special to
listen to (on headphones at least) is the AFX. I would not want to be
without it.  And in all other respects the K3 is a very fine radio indeed.

73 Stephen G4SJP

K3 #980



On 27/04/2009 21:43, "WA6L" <wa6l at arrl.net> wrote:

> 
> 
> 
> Hi, Roy,
> 
> As I approach a year's ownership of the K3, I have to say that there are
> very few times that I find the NR capability to be useful.  On a very noisy
> band and with reasonably wide bandwidths (> 800 Hz) the NR can work well,
> but never without pressing the Level button and optimizing the setting each
> time.
> 
> When I compare the K3's NR with my K2's, the K2 seems far superior to me.
> It may be because the K2 does its DSP at the audio instead of the IF, or it
> may be that the K2 implements longer FIR filters.  Whatever the reason, the
> K2's noise reduction works much better and in my shack is left on almost all
> the time.
> 
> Both the K3 manual and the Wikipedia explanation of the K3 noise reduction
> recommend using NR only with a wide bandwidth, and imply that it is not as
> effective on SSB as it is on CW.  I concur with these recommendations, but I
> have to say that I agree with you.  The NR implementation could have been
> done much better.
> 
> 73,
> 
> John
> 
> 
> 
> Roy Morris-6 wrote:
>> 
>> When I turn on NR the audio noise level goes down.  When a SSB signal is
>> received the audio peaks.  I have my RX EQ set flat.  In these peaks there
>> are resonances in my internal speaker (if I use it) as well as my two
>> external speakers that plainly makes noise reduction unpleasant.  It can
>> be minimally tolerated at F-1-1 level with speakers.  It is somewhat more
>> tolerable with a good headset.  Part of the problem may be in speaker
>> response, but I also think a big part of the problem is in the noise
>> reduction algorythms.   If noise reduction is not recommended with reduced
>> bandwidth in CW, and unpleasant artifacts occur in SSB; then I find NR to
>> be useless.  I hope the discussion of white noise and pink noise will lead
>> to something that will improve the noise reduction function in the K3.
>> Roy Morris  W4WFB
>>