diff --git a/presentation/transcript.md b/presentation/transcript.md
index 4e02f51..f1c8228 100644
--- a/presentation/transcript.md
+++ b/presentation/transcript.md
@@ -43,6 +43,8 @@ Hobbyists in this field enjoy a mix of technical experimentation, global communi
 
 
 
+Approx. 35 minutes of talking(including the optional). Can reduce it to 30. I would greatly appreciate if you gave me feedback on this rough transcript.
+
 # What hardware do we use? (5 min~)
 
 ## Radios