No Heartbeat Packets Recieved : cannot connect Pixhawk PX4


I am trying to connect PX4 Pixhawk with Mission Planner,
This is not the first time someone is connecting this multirotor controller… the reason that I am trying to connect is that it doesnt respond to the HK6S remote control…
I am newbie with that so Maybe I am doing sumething wrong
I chose the COM11 in the list and 115200,
On the device manager I can see under COM11 the PX4 FMU

Please help me!
Thanks in advance,

hi alon,
can we chat on facebook?