Corrected some typos.

applications/lofar1/FilterTaskForce/readme_FilterTaskForce.txt

 2021-12-7 Eric Kooistra (Jira L2SDP-215)
 
-Invertigation of FilterTaskForce.zip contents.
+Investigation of FilterTaskForce.zip contents.
 
 1) Scope
 2) FilterTaskForce
@@ -16,7 +16,7 @@ Invertigation of FilterTaskForce.zip contents.
 I checked the FilterTaskForce.zip that Andre Gunst still had with documents
 and Matlab code for the Polyphase Filterbank that is used in LOFAR1.
 
-Unfortunately the documents and note are not very clear. The most useful
+Unfortunately the documents and notes are not very clear. The most useful
 things are:
 - the PFB drawings in filterbanks2.ppt
 - the filter specification in MeasurementsEffect.ppt
@@ -76,10 +76,10 @@ further analysis in LOFAR2 these files are copied to:
 
 * Dec 15  2003  Memoonbasebandshift.doc
   Idea to shift the bands per station, so that the subband aliasing decorrelates at
-  the centrals processing. Not used.
+  the centrals processing. This was not used further.
 
 * May 14  2004 'Problematic choice of the filter.doc'
-  Some knowns pros and cons of critically sampled and oversampled PFB
+  Some known pros and cons of critically sampled and oversampled PFB.
 
 * Nov 23  2004  MinuteFTF2806.doc : not clear and not useful.