diff --git a/notebooks/Gotthard2/Characterize_Darks_Gotthard2_NBC.ipynb b/notebooks/Gotthard2/Characterize_Darks_Gotthard2_NBC.ipynb
index 2b63c4f9b1e983cb556ddf6ba2480600553aa813..5c49f27a345585539a8d3e82fb34e05a0efd8d19 100644
--- a/notebooks/Gotthard2/Characterize_Darks_Gotthard2_NBC.ipynb
+++ b/notebooks/Gotthard2/Characterize_Darks_Gotthard2_NBC.ipynb
@@ -134,9 +134,7 @@
    "source": [
     "run_dc = RunDirectory(in_folder / f\"r{run_nums[0]:04d}\")\n",
     "proposal = list(filter(None, str(in_folder).strip('/').split('/')))[-2]\n",
-    "file_loc = raw_data_location_string(proposal, run_nums)\n",
-    "da_to_source = gotthard2lib.map_da_to_source(\n",
-    "    karabo_da, receiver_affixes, receiver_template, run_dc)"
+    "file_loc = raw_data_location_string(proposal, run_nums)"
    ]
   },
   {
@@ -235,7 +233,10 @@
     "else:\n",
     "    karabo_da = list(da_to_pdu.keys())\n",
     "\n",
-    "print(f\"Processing {karabo_da}\")"
+    "print(f\"Processing {karabo_da}\")\n",
+    "\n",
+    "da_to_source = gotthard2lib.map_da_to_source(\n",
+    "    karabo_da, receiver_affixes, receiver_template, run_dc)"
    ]
   },
   {
diff --git a/notebooks/Gotthard2/Correction_Gotthard2_NBC.ipynb b/notebooks/Gotthard2/Correction_Gotthard2_NBC.ipynb
index 3a0f6234ca23e2088ee72ddd73ff331ce6a1bd3c..cc5859219033cbc0273f320d5d2835d0efe3cdbf 100644
--- a/notebooks/Gotthard2/Correction_Gotthard2_NBC.ipynb
+++ b/notebooks/Gotthard2/Correction_Gotthard2_NBC.ipynb
@@ -239,6 +239,9 @@
     "    db_modules = [da_to_pdu[da] for da in karabo_da]\n",
     "\n",
     "print(f\"Process modules: {db_modules} for run {run}\")\n",
+    "if len(receiver_affixes) != len(karabo_da):\n",
+    "    raise ValueError(\n",
+    "        \"receiver_affixes & karabo_da are not the same length\")\n",
     "\n",
     "da_to_source = gotthard2lib.map_da_to_source(\n",
     "    karabo_da, receiver_affixes, receiver_template, run_dc)\n",
diff --git a/src/cal_tools/gotthard2/gotthard2lib.py b/src/cal_tools/gotthard2/gotthard2lib.py
index d6fa4eba67935baffbcf460ad68a3379212d32f4..bf62d9083e1cedb6dab5312d530e85326b1e5c8c 100644
--- a/src/cal_tools/gotthard2/gotthard2lib.py
+++ b/src/cal_tools/gotthard2/gotthard2lib.py
@@ -5,12 +5,7 @@ from typing import List, Union
 import extra_data
 
 
-def map_da_to_source(
-    da, affixes, template, dc):
-    if len(affixes) != len(da):
-        raise ValueError(
-            "receiver_affixes & karabo_da are not the same length")
-
+def map_da_to_source(da, affixes, template, dc):
     da_to_source = {}
     for da, aff in zip(da, affixes):
         sources = dc.select(f"*{template.format(aff)}:daqOutput").all_sources