Here is the simplest command example I can show you, that uses the iTach to lower the volume on my Sceptre LCD TV:
<?xml version="1.0" encoding="utf-16"?>
<command id="620" name="sceptre vol down" enabled="true" alwaysOn="False" confirm="False" requiredConfidence="0" loop="False" loopDelay="0" loopMax="0" description="">
<action>
<cmdType>TCP.Single.WriteLn</cmdType>
<cmdString>sendir,1:3,1,39808,2,1,96,24,48,24,48,24,24,24,24,24,48,24,24,24,24,24,48,24,24,24,24,24,24,24,24,3980&&192.168.0.134&&4998</cmdString>
<cmdRepeat>1</cmdRepeat>
</action>
<phrase>sceptre vol down</phrase>
</command>
This command uses the TCP.Single.WriteLn action which opens a connection, sends the data, appends a carriage return, and then closes the connection.
There are other methods that may be preferable that keep a connection open and can get feedback from the device...