[Elecraft] Elecraft technology >> K2+

[Bill Coleman]

On 12/27/03 10:06 AM, Bill Tippett at btippett@alum.mit.edu wrote:

>N2EY wrote:
> > In one way, the K2 goes back to even earlier, single-band superhet
> > design. That's why its dynamic range figures are so good. Most rig
> > manufacturers aren't likely to move back to this simpler design, largely
> > because they don't want to give up general coverage receive.
>
>         I hope your last statement is wrong.  I believe the K2 and Orion's 
>Main RX
>are so superior that they may cause some manufacturers to rethink the need 
>for
>general coverage.

I don't see the Japanese manufacturers giving up general coverage 
receiption. If anything, we've seen the opposite trend. Wide receivers 
have also weakened the performance of VHF and UHF receivers, making them 
more subsceptable to intermod.

The Omni V showed that amatuer-only can give superior performance many 
years ago, yet there has been no change.

>Elecraft's K2 design has the basics of an excellent 
>contest
>radio, but it needs attention in two main areas to be truly competitive:
>
>1.  Ergonomics...for someone whose hand span exceeds the entire front panel
>width by 1.5" and with finger size to match....for someone who typically 
>spends
>hours in front of the radio in a contest and wants a minimum of menu changes
>(e.g. single-touch access to different filter BW's, etc)...panel readability
>for someone whose eyesight is not what it once was.

Realistically, there are only a few things that the K2 needs to improve 
in its front panel:

* current filter indication on display
* one-button access to the Rx antenna port. (toggle)
* DSP indication on display and easy-access controls

>2.  Replacing the programmable crystal filter with fixed BW 8-pole filters
>and <2:1 shape factors (quite achievable at the K2's IF).  The current filter
>has a ~3:1 shape factor which may be one reason the K2's performance degrades
>for IMD and BDR at signal spacings under 5 kHz.

In my experience, the K2 CW filters, while they don't have the best shape 
factor, perform admirably because of the other fine characteristics of 
the receiver, particularly the lack of IMD compared to a number of 
transceivers with wideband PLL noise.

The SSB filter could definitely be improved, although it isn't bad, even 
for contest use. The DSP cleans it up quite a bit.

>         With the addition of a K2+ model for performance-oriented contesters
>and DXers in the <$2k range, I believe Elecraft could dramatically expand 
>their
>market while maintaining their original target market for the K2.  Someone is
>going to do this eventually, and it might as well be Elecraft since the K2 is
>already very close to what is needed IMHO.

Once can't increase the front panel of the K2 much without radically 
changing the construction technique used. It might work to put in one 
more column of buttons and a slightly wider display, or a few low-power 
LEDs.

One difficulty with a contest-oriented K2+ is that the costs of the 
changes would have to be bourne only by K2+ sales, not over the K2 kit in 
general. The K2 is currently a great compromise between the QRP, 
battery-powered, backpacking utility radio and a overall HF radio. 

Bill Coleman, AA4LR, PP-ASEL        Mail: aa4lr@arrl.net
Quote: "Not within a thousand years will man ever fly!"
            -- Wilbur Wright, 1901