[Elecraft] k3 NR Audio level increase

[Joe Planisky]

Don,

Try this:

1. Set mode to CW, BW to 2.00, RX EQ = flat.

2. With no signal tuned in, hold NR and set to F4-4. Tap NR twice to  
turn off NR.

3. Tune in an S9 signal, or better yet, use a signal generator (I use  
an XG2).

4. Set RF gain to max, AF gain for a comfortable volume.

5. Tap NR to turn on noise reduction. (You might want to keep one hand  
on the AF gain control :-)

On my K3 (with FW 3.11), turning on NR under these conditions boosts  
the audio output voltage by 17.2 dB according to the built-in AFV meter.

Using less aggressive NR parameters results in less of a boost, down  
to 6.3 dB at F1-1.

Now tune in a weak signal (say, S3) and repeat the steps.  The boost  
is still there, but very much reduced (On my rig at S3 and NR=F4-4,  
the boost is 6.3 dB, at NR=F1-1 it's 1.4 dB)

Now imagine trying to copy a signal that rapidly fades between S3 and  
S9 with NR on.

73
--
Joe KB8AP


On Apr 25, 2009, at 4:35 AM, Don Wilhelm wrote:

> Terry,
>
> I do not experience anything like that on my K3.  What NR parameters  
> are
> you using?
> [...]
> 73,
> Don W3FPR
>
>
> G4POP wrote:
>> I see that the dramatic increase in audio level when NR is turned  
>> on has been
>> mentioned a couple of times but I can find no solution for this  
>> mentioned in
>> the forum and the latest firmware 3.11 has not cured it.
>> [...]
>> Terry G4POP
>>
>>