diff --git a/pytec/tec_qt.py b/pytec/tec_qt.py
index 7ac6560..e1098ae 100644
--- a/pytec/tec_qt.py
+++ b/pytec/tec_qt.py
@@ -29,10 +29,10 @@ def get_argparser():
 
 
 class ClientWatcher(QObject):
-    fan_update = pyqtSignal(object)
-    pwm_update = pyqtSignal(object)
-    report_update = pyqtSignal(object)
-    pid_update = pyqtSignal(object)
+    fan_update = pyqtSignal(dict)
+    pwm_update = pyqtSignal(list)
+    report_update = pyqtSignal(list)
+    pid_update = pyqtSignal(list)
 
     def __init__(self, parent, client, update_s):
         self.update_s = update_s
@@ -60,7 +60,7 @@ class ClientWatcher(QObject):
         self.running = False
         self.watch_task.cancel()
 
-    @pyqtSlot()
+    @pyqtSlot(float)
     def set_update_s(self, update_s):
         self.update_s = update_s
 
@@ -118,7 +118,8 @@ class MainWindow(QtWidgets.QMainWindow, Ui_MainWindow):
         self.fan_group.setEnabled(hw_rev_d["settings"]["fan_available"])
         self.fan_pwm_recommended = hw_rev_d["settings"]["fan_pwm_recommended"]
 
-    def fan_update(self, fan_settings):
+    @pyqtSlot(dict)
+    def fan_update(self, fan_settings: dict):
         logging.debug(fan_settings)
         if fan_settings is None:
             return