diff --git a/demo.rb b/demo.rb
index ea685e6..7bb5af7 100755
--- a/demo.rb
+++ b/demo.rb
@@ -1,6 +1,6 @@
 #!/usr/bin/env ruby
 # encoding: utf-8
-# ruby: 2.2 
+# ruby: 1.9
 require 'serialport'
 require './telegram'
 
@@ -11,11 +11,11 @@ DEBUG = false
 # send query/send telegram and return answer
 def comm(query,data=nil)
   telegram = Telegram.new(query,data)
-  puts("< "+(telegram.pack.bytes.collect{|b| "%02x" % b})*" ") if DEBUG
+  puts("< "+(telegram.pack.bytes.to_a.collect{|b| "%02x" % b})*" ") if DEBUG
   @serial.write(telegram.pack)
   answer = @serial.readpartial(3+16+1+2)
   raise "no answer received to query #{query}" if !answer or answer.empty?
-  puts("> "+(answer.bytes.collect{|b| "%02x" % b})*" ") if DEBUG
+  puts("> "+(answer.bytes.to_a.collect{|b| "%02x" % b})*" ") if DEBUG
   telegram = Telegram.parse(answer)
   raise "malformed answer" unless telegram
   raise telegram.to_s if (telegram.object==0 and telegram.data.length==2 and telegram.data[0]==0xff) or (telegram.object==255 and telegram.data[0]!=0)
@@ -50,13 +50,13 @@ def set_values (voltage=nil,current=nil,protection=false)
     raise "#{voltage} out of voltage range [0-#{query[2]*nominal[0]}]" if voltage<0 or voltage>query[2]*nominal[0]
     comm(54,[0x10,0x10]) # enable remote
     value = voltage*25600.0/nominal[0]
-    comm(query[0],[value].pack('n').bytes)
+    comm(query[0],[value].pack('n').bytes.to_a)
   end
   if current then
     comm(54,[0x10,0x10]) # enable remote
     raise "#{current} out of current range [0-#{query[2]*nominal[1]}]" if current<0 or current>query[2]*nominal[1]
     value = current*25600.0/nominal[1]
-    comm(query[1],[value].pack('n').bytes)
+    comm(query[1],[value].pack('n').bytes.to_a)
   end
   voltage = comm(query[0]).data.pack("C*").unpack("n")[0]/25600.0
   current = comm(query[1]).data.pack("C*").unpack("n")[0]/25600.0
diff --git a/mitm.rb b/mitm.rb
index 35d3875..813513a 100755
--- a/mitm.rb
+++ b/mitm.rb
@@ -1,6 +1,6 @@
 #!/usr/bin/env ruby
 # encoding: utf-8
-# ruby: 2.2
+# ruby: 1.9
 require 'serialport'
 require './telegram'
 
diff --git a/telegram.rb b/telegram.rb
index 6b7cd29..7ba56cd 100644
--- a/telegram.rb
+++ b/telegram.rb
@@ -1,5 +1,5 @@
 # encoding: utf-8
-# ruby: 2.2 
+# ruby: 1.9
 
 class Telegram
   attr_accessor :direction, :cast, :transmission, :node, :object, :data
@@ -87,7 +87,7 @@ class Telegram
     # check there are at least 5 bytes (minimum message size)
     return nil if telegram==nil
     return nil if telegram.length<5
-    bytes = telegram.bytes # get bytes
+    bytes = telegram.bytes.to_a # get bytes
     to_return = new(bytes[2]) # new Telegram
     # parse start delimiter (SD)
     length = bytes[0]&0x0f # get length