Power Query Split text by postion user insterface

Hi,

Can someone help or point me in the direction of information regarding the user interface for split column

essentially I have been trying to do this ;

Table.TransformColumns(  Source, {"Text", each Splitter.SplitTextByPositions ( 0..Text.Length(_)}  ) (_) } )

but using the interface , can't figure it out , help.

Richard.