#!/usr/bin/env perl

# fm class calculator

sub Print {
printf "\n\nFM Station Class %s\n".
       "-------------------\n\n",$class;
printf "         Maximum ERP : %.1f kW\n\n",$kw;
printf "        Maximum HAAT : %d meters (%.2f feet)\n\n",$haat,(3.281 * $haat);
printf "     Primary service : %d dBu, %.2f mV/m\n".
       "     contour\n\n",$dbu,$mvm;
printf " Distance to primary : %.2f km (%.2f miles)\n".
       " service contour\n\n",$pro,$prom;
printf "  Distance to 70 dBu : %.2f km (%.2f miles)\n".
       "  or 3.16 mV/m\n  contour\n\n",$db70,$db70m;
}

print "\n\n\t\tFM Station Classes and Service Contours\n\n";

while (!$_) {
	SEL:
       	print  "Enter FM station class (a,b,b1,c3,c2,c1,c): ";
	chomp($_ = <STDIN>);
}

if (/^a/i) {

	$class = "A";
	$kw = 6;
	$haat = 100;
	$dbu = 60;
	$mvm = 1;
	$pro = 28.3;
	$prom = $pro / 1.609;
	$db70 = 16.2;
	$db70m = $db70 / 1.609;
}

elsif (/^b1/i) {

	$class = "B1";
	$kw = 25;
	$haat = 100;
	$dbu = 57;
	$mvm = 0.71;
	$pro = 44.7;
	$prom = $pro / 1.609;
	$db70 = 23.2;
	$db70m = $db70 / 1.609;
}

elsif (/^b/i) {  

	$class = "B";
	$kw = 50;
	$haat = 150;
	$dbu = 54;
	$mvm = 0.50;
	$pro = 65.1;
	$prom = $pro / 1.609;
	$db70 = 32.6;
	$db70m = $db70 / 1.609;
}              

elsif (/^c3/i) { 

	$class = "C3";
	$kw = 25;
	$haat = 100;
	$dbu = 60;
	$mvm = 1;
	$pro = 39.1;
	$prom = $pro / 1.609;
	$db70 = 23.2;
	$db70m = $db70 / 1.609;
}

elsif (/^c2/i) { 

	$class = "C2";
	$kw = 50;
	$haat = 150;
	$dbu = 60;
	$mvm = 1;
	$pro = 52.2;
	$prom = $pro / 1.609;
	$db70 = 32.6;
	$db70m = $db70 / 1.609;
}            

elsif (/^c1/i) {

	$class = "C1";
	$kw = 100;
	$haat = 299;
	$dbu = 60;
	$mvm = 1;
	$pro = 72.3;
	$prom = $pro / 1.609;
	$db70 = 50;
	$db70m = $db70 / 1.609;
}

elsif (/^c/i) { 

	$class = "C";
	$kw = 100;
	$haat = 600;
	$dbu = 60;
	$mvm = 1;
	$pro = 91.8;
	$prom = $pro / 1.609;
	$db70 = 67.7;
	$db70m = $db70 / 1.609;
}

else {
	goto SEL;
}

&Print;