[Elecraft] K3 NB Generates noise

[Fred Jensen]

Ed,

First off, make sure you are running the latest production firmware.  It 
made some major improvements in the NB and NR functions.

The very nature of any noise blanker will distort the signal and using 
it is a trade-off between that distortion ... which sounds a lot like 
"noise" ... and the real noise mixed in with the desired signal.  The NB 
literally punches holes in the signal during noise pulses.  As you go to 
higher numbers, the blanker gets more aggressive, and typically, the 
distortion increases.

The NAR, MID, and WID settings determine the width of the "holes."  For 
example, our electric fence periodically starts "ticking" when weeds 
grow up under it in the spring.  The noise pulses are very narrow, and a 
NAR-1 or NAR-2 setting takes them totally out and does not introduce any 
distortion that I can hear.  A higher NAR setting seems to take them 
out, but replaces them with the distortion from the holes in the signal, 
which sounds a lot like the original noise pulses. :-)

73,

Fred K6DGW
- Northern California Contest Club
- CU in the 2012 Cal QSO Party 6-7 Oct 2012
- www.cqp.org

On 7/18/2012 2:28 PM, Ed Stallman wrote:
> I finished K3 Kit 6644 yesterday and noticed today when using the NB
> on 6m that it the NB will generate noise only on a few different
> levels ! With NB Level on then DSP set to off .. I now turn
> IF-NAR  from off  through the numbers 1 to 7 ...when I get to
> IF-NAR  6 and 7 it is much noisier then 2,3,4, or 5 with 4 being
> best  ! Is this normal ? I was thinking the higher numbers would
> reduce more noise ? Using IF-MID and WID 1 has more noise and 7 is less