#!/usr/bin/env perl

# Attenuation calculator for Times Microwave LMR series coax
# A service of Green Bay Professional Packet Radio, www.dct.com/~multiplx

print "\n\n\t\tAttenuation calculator for Times Microwave LMR series coax\n\n";

while (!m/^([0-9.]+)(k|K|m|M|g|G|h|H+)$/) {
	print "\nk = kilohertz\n".
              "m = megahertz\n".
              "g = gigahertz\n\n".
              "Enter the frequency  [value][unit]: ";
	chomp($_ = <STDIN>);
}
if (m/^([0-9.]+)(k|K|m|M|g|G|h|H+)$/) {
        $frq = $1;
        $unit = $2;
}
if ($unit =~ /k/i) {
	# kHz to MHz
	$frq = $frq / 1000;
}
elsif ($unit =~ /m/i) {
	# MHz to MHz
	$frq = $frq;
}
elsif ($unit =~ /g/i) {
	# GHz MHz
	$frq = $frq * 1000;
}

undef $_;
while (!m/^([0-9.]+)(cm|CM|m|M|in|IN|ft|FT+)$/) {
	print "\ncm = centimeters\n".
              "m  = meters\n".
              "in = inches\n".
              "ft = feet\n\n".
              "Enter the length  [value][unit]: ";
	chomp($_ = <STDIN>);
}
if (m/^([0-9.]+)(cm|CM|m|M|in|IN|ft|FT+)$/) {
        $len = $1;
        $unit = $2;
}
if ($unit =~ /cm/i) {
	# cm to ft
	$len = $len / 30.48;
}
elsif ($unit eq "m" or $unit eq "M") {
	# m to ft
	$len = $len / 0.3048;
}
elsif ($unit =~ /in/i) {
	# in to ft
	$len = $len / 12;
}
elsif ($unit =~ /ft/i) {
	# ft to ft 
	$len = $len;
}

while (!$type) {
	print "100\n".
	      "195\n".
	      "200\n".
	      "240\n".
              "300\n".
              "400\n".
	      "500\n".
	      "600\n".
	      "900\n".
              "1200\n".
              "1700\n\n".
	      "Enter cable type (LMR-???): ";
	chomp($type = <STDIN>);
	$type =~ tr/0-9//csd;
}

if ($type eq 100) {
	# LMR-100
	$imp = "50 ohms";
	$min_bend = "0.25 in (6.4 mm)";
	$weight = "0.015 lbs/ft (0.02 kG/m)"; $lbs = 0.015;
	$cutoff = "90 GHz";
	$vel = "66%";
	$peakpwr = "0.6 kW";	
	$cap = "30.8 pF/ft (101.1 pF/m)";
	$ind = "0.077 uH/ft (0.25 uH/m)";
	$att = (0.70914 * sqrt $frq) + (0.00174 * $frq);
}

elsif ($type eq 195) {
	# LMR-195
	$imp = "50 ohms";
	$min_bend = "0.5 in (12.7 mm)";
	$weight = "0.021 lbs/ft (0.03 kG/m)"; $lbs = 0.021;
	$cutoff = "41 GHz";
	$vel = "80%";
	$peakpwr = "2.5 kW";
	$cap = "24.3 pF/ft (79.70 pF/m)";
	$ind = "0.064 uH/ft (0.21 uH/m)";
	$att = (0.35686 * sqrt $frq) + (0.00047 * $frq);
}

elsif ($type eq 200) {
	# LMR-200
	$imp = "50 ohms";
	$min_bend = "0.5 in (12.7 mm)";
	$weight = "0.022 lbs/ft (0.03 kG/m)"; $lbs = 0.022;
	$cutoff = "39 GHz";	
	$vel = "83%";
	$peakpwr = "2.5 kW";
	$cap = "24.5 pF/ft (80.4 pF/m)";
	$ind = "0.061 uH/ft (0.20 uH/m)";
	$att = (0.32090 * sqrt $frq) + (0.00033 * $frq)
}

elsif ($type eq 240) {
	# LMR-240
	$imp = "50 ohms";
	$min_bend = "0.75 in (19.1 mm)";	
	$weight = "0.034 lbs/ft (0.05 kG/m)"; $lbs = 0.034;
	$cutoff = "31 GHz";
	$vel = "84%";
	$peakpwr = "5.6 kW";
	$cap = "24.2 pF/ft (79.4 pF/m)";
	$ind = "0.060 uH/ft (0.20 uH/m)";
	$att = (0.24208 * sqrt $frq) + (0.00033 * $frq)
}

elsif ($type eq 300) {
	# LMR-300
        $imp = "50 ohms";
	$min_bend = "0.88 in (22.2 mm)";	
	$weight = "0.055 lbs/ft (0.08 kG/m)"; $lbs = 0.055;
	$cutoff = "24.5 GHz";
        $vel = "85%";
        $peakpwr = "10 kW";
	$cap = "24.1 pF/ft (79.1 pF/m)";
	$ind = "0.060 uH/ft (0.20 uH/m)";
	$att = (0.19193 * sqrt $frq) + (0.00033 * $frq)
}

elsif ($type eq 400) {
	# LMR-400
	$imp = "50 ohms";
	$min_bend = "1.0 in (24.5 mm)";
	$weight = "0.068 lbs/ft (0.10 kG/m)"; $lbs = 0.068;
	$cutoff = "16.2 GHz";	
	$vel = "85%";
	$peakpwr = "16 kW";
	$cap = "23.9 pF/ft (78.4 pF/m)";
	$ind = "0.060 uH/ft (0.20 uH/m)";
	$att = (0.12229 * sqrt $frq) + (0.00026 * $frq);
}

elsif ($type eq 500) {
        # LMR-500
        $imp = "50 ohms";
	$min_bend = "1.3 in (31.8 mm)";
	$weight = "0.097 lbs/ft (0.14 kG/m)"; $lbs = 0.097;
	$cutoff = "12.6 GHz";	
	$vel = "86%";
	$peakpwr = "22 kW";
	$cap = "23.6 pF/ft (77.4 pF/m)";
	$ind = "0.059 uH/ft (0.19 uH/m)";
	$att = (0.09659 * sqrt $frq) + (0.00026 * $frq);		
}

elsif ($type eq 600) {
        # LMR-600
        $imp = "50 ohms";
	$min_bend = "1.5 in (38.1 mm)";
	$weight = "0.131 lbs/ft (0.20 kG/m)"; $lbs = 0.131;
	$cutoff = "10.3 GHz";	
	$vel = "87%";
	$peakpwr = "40 kW";	
	$cap = "23.4 pF/ft (76.8 pF/m)";
	$ind = "0.058 uH/ft (0.16 uH/m)";
	$att = (0.07555 * sqrt $frq) + (0.00026 * $frq);
}

elsif ($type eq 900) {
        # LMR-900
        $imp = "50 ohms";
	$min_bend = "3.0 in (76.2 mm)";
	$weight = "0.266 lbs/ft (0.40 kG/m)"; $lbs = 0.266;
	$cutoff = "6.9 GHz"; 
	$vel = "87%";
	$peakpwr = "62 kW";
	$cap = "23.4 pF/ft (76.8 pF/m)";
	$ind = "0.058 uH/ft (0.19 uH/m)";
	$att = (0.05177 * sqrt $frq) + (0.00016 * $frq);
}

elsif ($type eq 1200) {
        # LMR-1200
        $imp = "50 ohms";
	$min_bend = "6.5 in (165.1 mm)";
	$weight = "0.448 lbs/ft (0.67 kG/m)"; $lbs = 0.448;
	$cutoff = "5.2 GHz";
	$vel = "88%";
	$peakpwr = "90 kW";
	$cap = "23.1 pF/ft (75.8 pF/m)";
	$ind = "0.056 uH/ft (0.18 uH/m)";
	$att = (0.03737 * sqrt $frq) + (0.00016 * $frq);
}

elsif ($type eq 1700) {
        # LMR-1700
        $imp = "50 ohms";
	$min_bend = "13.5 in (342.9 mm)";	
	$weight = "0.736 lbs/ft (1.10 kG/m)"; $lbs = 0.736;
	$cutoff = "3.6 GHz";
	$vel = "89%";
	$peakpwr = "202 kW";
	$cap = "22.8 pF/ft (74.8 pF/m)";	
	$ind = "0.057 uH/ft (0.19 uH/m)";
	$att = (0.02646 * sqrt $frq) + (0.00016 * $frq);
}
else {
        # LMR-400
	print "\n$type not valid, using default cable (LMR-400)\n";
	$type = 400;
        $imp = "50 ohms";
        $min_bend = "1.0 in (24.5 mm)";
        $weight = "0.068 lbs/ft (0.10 kG/m)"; $lbs = 0.068;
        $cutoff = "16.2 GHz";
        $vel = "85%";
        $peakpwr = "16 kW";
        $cap = "23.9 pF/ft (78.4 pF/m)";
        $ind = "0.060 uH/ft (0.20 uH/m)";
        $att = (0.12229 * sqrt $frq) + (0.00026 * $frq);
}

$att_ft = $att / 100;

print "\n\nLMR-$type Specifications:\n\n".
      " Minimum bend radius : $min_bend\n".
      "          Impendance : $imp\n".
      "              Weight : $weight\n".
      "    Cutoff frequency : $cutoff\n".
      "     Velocity factor : $vel\n".
      "          Peak power : $peakpwr\n".
      "         Capacitance : $cap\n".
      "          Inductance : $ind\n";
printf "  Total cable weight : %.3f pounds (%.3f kG)\n\n", $len * $lbs, ($len * $lbs) * 0.45359237;
print "           Frequency : $frq MHz\n";
printf "         Attenuation : %.3f dB / foot (%.3f dB / meter)\n", $att_ft, $att_ft * 0.3048;
printf "   Total attenuation : %.4f dB over %.3f feet (%.3f meters)\n\n", $len * $att_ft, $len, $len * 0.3048;