Dude you rock! For the most part I modified your example so that it almost works as expected. I had to blow away the UTF-8 encoding part due to errors. Then I modified the '$i (1..$#unique_accounts)' so output would not be zero based. Then I included some added conditions so that it would not process header & trailer records. So output is:
1:#########
2:#########
3:#########
4:#########
5:#########
total: 370659
uniq : 6
Sorry but I cannot show actual values. Notice there are 5 unique values (which is correct) yet the 'uniq' counter reads 6. Also total lines processed equals 370659, it should only equal 370657. It is obviously processing header & trailer records. Here is your example with my changes:

use strict;
use warnings;
use List::MoreUtils qw(uniq);

my $char_at=10;
my $num_chars=50;
open my $fh, $ARGV[0]
#open my $fh, '<:encoding(UTF-8)', $ARGV[0]
    or die "Could not open '$ARGV[0]' $!";
my @trnAccounts;
while (my $line = <$fh>) {
    my $val = substr($line, $char_at, $num_chars);
    if ($val eq 'H' or $val eq 'T') {
        my $output = $line;
    }else {    
        chomp $line;
        next unless $line && length($line) >= $char_at;
        push @trnAccounts, substr($line, $char_at, $num_chars);
    }
}
my @unique_accounts = uniq(@trnAccounts);
for my $i (1..$#unique_accounts) {
    print $i, ":", $unique_accounts[$i], "\n";
}
print "total: ", scalar(@trnAccounts), "\n";
print "uniq : ", scalar(@unique_accounts), "\n";

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In reply to Re^2: Trying to print out only unique array values- by rickman1
in thread Trying to print out only unique array values- by rickman1

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