diff --git a/main.py b/main.py
index fe5fcee..7c5566e 100755
--- a/main.py
+++ b/main.py
@@ -245,6 +245,8 @@ class MainWindow(Gtk.Window):
             uid =  self.transmissions[self.transmission_list.get_selected_row().get_index()][0]
             trxData = db.get_transmission_data(uid)
         except AttributeError:
+            # when adding a new transmission, this function is called before any row is selected and logs
+            # an error. I don't know when or why that happens, but this does the job.
             return
         except:
             log.critical(error)