diff --git a/documentation/09 _ Select Waveforms.help.md b/documentation/09 _ Select Waveforms.help.md
index 56a38d2bb7d57d3b29b6b00ebe3ec74aceb21a54..7f4a3a8d80cda885ad469d5c100c4ab1e9ac4095 100644
--- a/documentation/09 _ Select Waveforms.help.md	
+++ b/documentation/09 _ Select Waveforms.help.md	
@@ -44,10 +44,12 @@ checked,  a warning will be created, "Checked data streams will be ignored
 for RT130 data type."
 
 ## Displaying waveform channels
-If one of TPS or RAW checkboxes aren't checked which means no data need to be
-displayed,  all the waveform selected will be ignored.
-
-To display waveform channels,  user need to check:
+TPS needs to be checked to display Time-Power-Squared of waveform.
+RAW needs to be checked to display actual signal of waveform.
 + <img alt="TPS" src="images/select_waveform/select_TPS.png" height="30" />: to diplay Time-Power-Squared of the selected waveform data 
 + <img alt="RAW" src="images/select_waveform/select_RAW.png" height="30" />: and check RAW to display the actual selected waveform data.
-<br />
\ No newline at end of file
+<br />
+
+If any of waveform is checked but no TPS or RAW is checked,
++ For RT130, the program will read event of the selected data stream.
++ For MSeed, the program will pop up message request user to clear waveform selection or select either TPS or RAW.
\ No newline at end of file
diff --git a/sohstationviewer/view/main_window.py b/sohstationviewer/view/main_window.py
index 188d8940e4094b65145ca64c9b497c7011eecf93..55229391942838e45a3383ae4c3cf458eaab4cc8 100755
--- a/sohstationviewer/view/main_window.py
+++ b/sohstationviewer/view/main_window.py
@@ -386,9 +386,9 @@ class MainWindow(QtWidgets.QMainWindow, UIMainWindow):
         :rtype: List[str, int]
         """
         req_wf_chans = []
-        if ((self.all_wf_chans_check_box.isChecked()
-                or [ds for ds in self.ds_check_boxes if ds.isChecked()] != []
-                or self.mseed_wildcard_edit.text().strip() != "")
+        if (self.data_type != 'RT130' and
+                (self.all_wf_chans_check_box.isChecked()
+                 or self.mseed_wildcard_edit.text().strip() != "")
                 and not self.tps_check_box.isChecked()
                 and not self.raw_check_box.isChecked()):
             raise Exception(