Loop Back Test - Sticky?

Great documentation!!! (And I regularly read IBM mainframe docs.)
I followed the instructions and it behaved exactly as expected; a text version of ping.

I strung together some code to do the same thing. The problem is all I get back is rectangles under the serial monitor. Can you think of something to account for that?
Here's my code -

void setup() {
Serial.begin(9600);
pinMode(2, INPUT);
}

void loop() {
if (Serial.available() > 0) {
Serial.println(Serial.read());
}
}
}

Any help would be appreciated.

Regards,
kk