Please describe in as much detail as you can (assume we know nothing at all) what you do when you can get PuTTY to control the radio.
Full details are essential because you are probably just missing some very small thing.
To get the Arduino to display what it received from SoftwareSerial you can do something like this
ssByte = mySerial.read()
Serial.print(ssByte, HEX);
if (ssByte == 0x11) {
// etc
But please do not take this to mean that I think checking for 0x11 is correct - I have no idea until you give us the full details of what you do with PuTTY.
...R