diff --git a/frappy_psi/SR.py b/frappy_psi/SR.py
index 709de26..229350f 100644
--- a/frappy_psi/SR.py
+++ b/frappy_psi/SR.py
@@ -54,7 +54,7 @@ class XY(HasIO, Readable):
     time_const = {name: value for value, name in enumerate(
         ['10us', '20us', '50us', '100us', '200us', '500us', '1ms', '2ms', '5ms', '10ms',
          '20ms', '50ms', '100ms', '200ms', '500ms', '1s', '2s', '5s', '10s', '20s', '50s',
-         '100s', '200s', '500s', '1ks', '10ks', '20ks', '50ks', '100ks']
+         '100s', '200s', '500s', '1ks', '2ks', '5ks', '10ks', '20ks', '50ks', '100ks']
     )}
 
     tc = Parameter('time const. value', FloatRange(0.00005, 100000), unit='s', readonly=False)
@@ -146,12 +146,22 @@ class XY(HasIO, Readable):
         reply = self.comm('SEN.')  # range value
         return float(reply)
 
-    def write_range(self):
-        curr_value = self.read_range()
-        new_value = self.value
-        c_ind = self.comparison(curr_value, new_value, self.sen_range)
-        self.read_irange()
-        return self.comm(f'SEN {c_ind}')
+    # def write_range(self, val):
+    #     curr_val = self.read_range
+    #     curr_idx = self.read_irange
+    #
+    #     close_val = None
+    #     min_diff = None
+    #
+    #     for idx, value in self.sen_range.items():
+    #         diff = abs(value - val)
+    #         close_idx = self.comparison(curr_val, value, self.sen_range)
+    #         if close_idx ?:
+    #             close_val = value
+    #             close_idx = close_idx
+    #             min_diff = abs(curr_val - close_val)
+    #
+    #     return self.comm(f'SEN {close_idx}')
 
     def read_nm(self):
         reply = self.comm('NOISEMODE')
@@ -166,21 +176,24 @@ class XY(HasIO, Readable):
         reply = self.comm('TC.')
         return float(reply)
 
-    def write_tc(self):
-        pass
-
-    def read_itc(self):
-        return int(self.comm('TC'))
-
-    def write_itc(self, new_itc):
-        curr_value = self.read_itc()
+    def write_tc(self, new_tc):
+        curr_value = self.read_tc()
         new_value = self.time_const[self.itc]
         c_ind = self.comparison(curr_value, new_value, self.time_const)
 
         if abs(curr_value - new_value) < c_ind:
-            if self.read_nm() == 1 and (5e-4 <= self.time_const[new_itc] <= 1e-2):
-                raise RangeError('not allowed with noisemode=1')
-            return self.comm(f'TC {new_itc}')
+            if self.read_nm() == 1 and (5e-4 <= self.time_const[new_tc] <= 1e-2):
+                raise RangeError('Not allowed with noisemode=1')
+            return self.comm(f'TC {new_tc}')
+
+    def read_itc(self):
+        return int(self.comm('TC'))
+
+    def write_itc(self, itc):
+        value = int(itc)
+        self.comm(f'TC {value}')
+        self.read_tc()
+        return value
 
     # phase and autophase
     def read_phase(self):