[Elecraft] K2 - (K2-100) aux I/O

[Don Wilhelm]

Gene,

You must NOT plug a standard serial cable into that 9 pin AUX connector. 
  It is not RS-232 although there are 3 RS-232 signal lines in the 
connector.  The remaining signals are internal K2 signals that are used 
with external Elecraft equipment like the KAT100, the KRC2 and the XV 
series transverters.
Plugging a full serial cable into the K2 can damage those signal lines 
and/or the RS-232 port (there are more than 3 wires in a standard serial 
cable.

You MUST use the special cable shown in the KIO2 or KPA100 manual.  It 
does not have to be very long, but it must be present.

That projection on the DE9 connector on your K2 is an effort by some 
builders to prevent using the wrong cable in the connector - it is not 
stock, but is a good idea.

Yes, to use a connector that has been modified, you will need to make a 
mating slot in your cable connector.  I am not certain where that 
modification is documented, it has been many years ago that someone 
presented the idea.

73,
Don W3FPR

On 1/9/2019 1:34 PM, Gene O wrote:
> I have a K2 with the 100W, K2/100, mounted in the top.  I want to obtain 
> a RS232 cable with male DB9 on one end and female on the other.
> 
> In order to make the connection in the back or the K2 it seems the male 
> plug needs to be modified.  That is a slot cut so that it fits the 
> key/tab that is on the connector mounted in the back of the K2/100.
> 
> Is there any problem with this as long as the cable just has the typical 
> 3 wires for RS232 data?
>