[Elecraft] Re: More Questions: K3

[wayne burdick]

Thom,

I'm sorry I missed this one. We've been overwhelmed by email the past 
few days. Lyle and I have been tag-teaming, covering most of the bases, 
we hope!

> On another list, some users who have both Drake equipment and K2's 
> have been discussing the relative merits of the Drake NoiseBlankers 
> versus the K2 NB.

The K3 noise blanker is a completely new design. It is being tested on 
a wide variety of noise sources. While it's impossible to say exactly 
how it would compare to other blankers on every noise type, I can 
assure you it's a significant enhancement. We studied several different 
design approaches before starting the KNB3, including the Drake 
circuit.

In addition, the K3 includes DSP-based both noise blanking and noise 
reduction features that can mitigate noise problems I.F. blankers can't 
touch, no matter how sophisticated.


>
> There have also been discussions relative to passband tuning.

The K3 includes passband tuning. It's designed to take maximum 
advantage of its large number of crystal roofing filters and I.F. DSP, 
in combination. There are two sets of controls: SHIFT/WIDTH, and 
HICUT/LOCUT. Tapping a single button switches between the two. An 
optimized DSP graphic on the LCD sits just above the knobs, and shows 
you at a glance whether the passband has been shifted or narrowed as a 
result of using these controls.

The most appropriate roofing filter is selected automatically as these 
controls are rotated. If you have one of our [pending] 
variable-passband crystal roofing filters installed, then the 1st I.F. 
bandwidth (crystal filter) will closely track the 2nd I.F. bandwidth 
(DSP). This is far superior to receivers that have only wide roofing 
filters and try to do the whole job at the DSP, as well as receivers 
that simply shift one filter against another at two different IFs.

Feel free to email me directly with further questions on this topic.

73,
Wayne
N6KR


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