convert xls file to txt file script in powershell

i need someone to write a powershell script (.ps1) that will convert xls file to a tab delimited text file. i will schedule a task in windows to run that script once a day. i only need someone to write the script. i already know how to schedule the task. the location of the file will be C:\Keystrok and the converted file will also be saved in the same folder.