php return statement in if statement

Maybee my question is somehow elementary or stupid, however i need to verify this.

I have a php function "functionA" which is repeatidely called in a for loop:

...
for($j=0; $j<$n_samples;$j++) {
    if($type=='triband') {
        functionA($arg1,$arg2);                 
    }
}
...

and my functionA:

...
functionA($arg1,$arg2) {
    $wide_avg_txon = substr($bit_sequence,0,1);
    if($wide_avg_txon==0)
    {
        echo " ---> is OFF...<br />";
    }
    else
    {
        echo " ---> is ON...<br />";
        // if is ON then skip execution of code inside the function
        return;
    }

    // DO SOME STUFF!
}
...

So simply i do not want to execute the rest of code inside functionA if "$wide_avg_txon==1" and i just want to continue executing the for loop for the next iteration!

Is the above code going to work? What is the difference between: 'return' and 'return false'? Is 'return false' going also to work:

...
if($wide_avg_txon==0)
    {
        echo " ---> is OFF...<br />";
    }
    else
    {
        echo " ---> is ON...<br />";
        // if is ON then skip execution of code inside the function
        return false;
    }

thanks!