[Elecraft] K2 USB to 9 Pin Cable (info)

[Harry Yingst]

 Please read what I posted and you will see it is correct
The color codes are from the USB-RS232-WE-1800-BT-0.0


    On Tuesday, June 4, 2019, 2:42:53 PM EDT, Don Wilhelm <donwilh at embarqmail.com> wrote:  
 
 Harry,

Before plugging that into the K2 AUX IO connector, the Green, Brown, and 
Red conductors must be cut or damage to the K2 and/or the adapter can be 
damaged.  Note that the connector on the K2 is labeled AUX IO, and that 
is for a reason - it is NOT RS-232.

At the very least, if that adapter ties RTS and CTS together, that will 
put +12 volts on the VRFDET internal K2 signal line and the K2 will not 
transmit with that condition present, and it may damage the MCU pin 2 
input.  If that pin is damaged, the K2 will transmit but will have no 
power control and the power will go to the maximum which will cause 
additional damage if that condition exists for more than a very short time.

Build the PC to K2 cable shown in the KIO2 and KPA100 manuals and plug 
it into that adapter or most any other FTDI USB to Serial adpater.

73,
Don W3FPR

On 6/4/2019 2:10 PM, Harry Yingst via Elecraft wrote:
> I'm passing this info along for those who may have a K2 and find this useful.
> 
> FTDI makes a USB to RS-232 Cable Part Number: USB-RS232-WE-1800-BT-0.0
> The cable has a USB plug on one end and is terminated in wires on the other end.
> --
> Here is the Pin-out to make a USB to K2 Cable
> 
> Color - Signal - Notes
> Yellow - RXD - Pin 2 on 9 Pin Connector - RS-232 Data In From K2
> Orange - TXD - Pin 3 on 9 Pin Connector - RS-232 Data Out To K2
> Black - Gnd - Pin 5 on 9 Pin Connector - Ground
> Green - RTS - Tied to CTS Line
> Brown - CTS - Tied to RTC Line
> Red - Power - Unused - 0.0v
> --