user6365: What is the timestamp used for the blocks on blockexplorer.com 
For example block 233969 has: 
Time: 2013-04-30 23:27:36 
is this time converted to 32bit hex for hash calculation, if so how ?

user403: In the network protocol, times are represented as Unix timestamps stored as unsigned 32-bit integers.

is this time converted to 32bit hex for hash calculation, if so how ?

Bitcoin uses a binary protocol. Nothing is hex. When viewing the binary data, your tools may display the data in hex, but you can't directly use these hex characters for hashing, etc.

6365: <p>What is the timestamp used for the blocks on blockexplorer.com 
For example block 233969 has: 
<strong>Time: 2013-04-30 23:27:36</strong> </p>

<p>is this time converted to 32bit hex for hash calculation, if so how ?</p>
 403: <p>In the network protocol, times are represented as <a href="http://en.wikipedia.org/wiki/Unix_time" rel="nofollow">Unix timestamps</a> stored as <em>unsigned</em> 32-bit integers.</p>

<blockquote>
  <p>is this time converted to 32bit hex for hash calculation, if so how ?</p>
</blockquote>

<p>Bitcoin uses a binary protocol. Nothing is hex. When viewing the binary data, your tools may <em>display</em> the data in hex, but you can't directly use these hex characters for hashing, etc.</p>
