[Elecraft] [K2] K2 PC Interface for N1MM

[Jim Brown]

On Sun, 10 Jan 2010 06:02:58 -0800 (PST), Tom KG3V wrote:

>I will give the homebrew interface a try and see how
>that works. 

Before I moved to CA, I was using a K2/100 extensively for 
contesting. The standard serial interface worked quite well, 
but NOT with the standard K2 cable, which is a dog for RFI if 
your TX antenna is close to your rig. 

To solve the RFI issue, simply rebuild the serial cable with 
twisted pair (like CAT5). See details in 

http://audiosystemsgroup.com/HamInterfacing.pdf  

That same pdf shows the control wiring needed -- only pins 2, 
3, and connector shell between computer and radio -- and pin 4 
plus the connector shell to send CW. Pin 4 drives the base of 
the standard NPN inverter transistor through a small value 
resitor (a few kOhms), collector drives the key line of the K2, 
emitter goes to common. 

Again, details in the pdf. 

BTW -- virtually all contest loggers use the same serial and 
parallel connections and signals to key radios, so if you build 
an adapter for one logger it will work for all. Another BTW -- 
the computers I've used for contest logging all run on either 
W2KPro or XPPro on IBM Thinkpads. No issues with those OSs. 

73,

Jim Brown K9YC