diff --git a/README.md b/README.md
index 37d06f3..7136b22 100644
--- a/README.md
+++ b/README.md
@@ -14,6 +14,8 @@
     - Coded differently after clearing the original source
     - Prevent malfunction by applying threshold
   5.stabilize and remove many warning messages - by Pullrequest and merge
+  6.Study on improvement method for cw keying - need idea
+    - set ADC Range value
 
 #NOTICE
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