[Elecraft] Spectrum Display for k2

[William Stewart]

Recently I have implemented a downconverter to convert the K2 IF to 
baseband so that the spectrum can be displayed on a PC using a SDR 
software package such as "NaP3". To route the IF out of the K2, I used a 
Z10000B buffer amplifier kit from Clifton Labs, and for the 
downconverter I used a special version of the Softrock Lite II Combined 
Receiver kit from Tony Parks at FiveDashInc. Tony offers these small 
receiver kits to be used as IF downconverters for a variety of 
transceivers. For the "sound card" I use a E-MU 0202 USB version from 
Creative Labs. I have a similar arrangement with my K3 using an LP Pan 
downconverter being driven by the K3's IF output. The K2 is different 
from the K3 in that it is a single-conversion design, so when operating 
CW the local Oscillator for the last conversion is usually just 600 Hz 
above the signal you are listening to, which is a bit of a distraction, 
but it does not diminish the usefulness of the display. For those who 
have not used a spectrum display, I would say you are missing quite a 
bit - once you have it, operating without it is like watching TV with 
your back turned to the screen. Not as much fun. And the control of the 
radio from a program like NaP3 is very convenient. I have made some 
screen captures of the spectrum display and I would be glad to forward 
these via direct email to anyone who is interested.

73,

Bill K5EMI