[Elecraft] K3 Serial Interface

[David Robertson]

K3 Owners,
In order to download and install new firmware do I need only
pin 2 (RXD), Pin 3 (TXD), and Pin 5 (Common or SER C) connected in my serial interface cable from the computer?

The schematic shows, in addition to the above, some handshake connections:
Pin 7 (RTS) and Pin 4 (DTR).
The reason I am asking is I plan to use the Rigblaster Pro to interface with my K3 and Not sure that the serial pass through connection contains the Pin 7 and 4 connections. I have already got successful remote operation with my K2 using the Rigblaster Pro. I am aware that the K2 doesn't use any handshake (Pin 4 and 7) connections for serial interface.

Thanks in advance.

73
Dave KD1NA