Timestamp 12:01:03.348 
0x014D TNDB 
-- 
Result Status: 1 
Source: 2 
Freq: 50 
Slice: 4 
Mode: 3 
Output: 234.209 
Diff: 390.009 
Dev: 89.909 
Timestamp 12:01:03.348 
0x014E TNDB 
-- 
Result Status: 1 
Source: 2 
Freq: 50 
Slice: 4 
Mode: 3 
Output: 234.209 
Diff: 390.009 
Dev: 89.909 

##</code><code>##

#!/usr/bin/perl

use warnings;
use strict;
use 5.10.0;

open my $fh, '<', 'data.txt' or die $!;

my $begin = 0;

while ( my $line = <$fh> ){

    chomp $line;
    $begin = 1 if $line =~ /0x014E/;
    next unless $begin;

    say $line and last if $line =~ /^Output:/;
}