diff --git a/requirements.txt b/requirements.txt
index 745b15e8c57a94e29b315f6d55af98cc2da5db05..d6929c0011d179e6f215668f6dde60fb64c8f938 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -2,4 +2,5 @@ h5py
 numpy
 astropy
 matplotlib
-numba
\ No newline at end of file
+numba
+scipy
\ No newline at end of file
diff --git a/scintillation/Calibrationlib.py b/scintillation/Calibrationlib.py
index 4ae11195a67bfeb2015e131af4a8c468e564283a..1e55130fe161f551c064773acd5ce1d75dd07990 100644
--- a/scintillation/Calibrationlib.py
+++ b/scintillation/Calibrationlib.py
@@ -49,12 +49,13 @@ def model_flux(calibrator, frequency):
     if calibrator in Cal_dict.keys():
         parameters = Cal_dict[calibrator]
     else:
-        raise ValueError(calibrator, "is not in the calibrators list")
+        parameters = [1., 0.]
+        # raise ValueError(calibrator, "is not in the calibrators list")
 
     flux_model = 0
     freqs = frequency * 1.e-3  # convert from MHz to GHz
     for j, p in enumerate(parameters):
-        flux_model += p * np.log10(frequency) ** j
+        flux_model += p * np.log10(freqs) ** j
     flux_model = 10 ** flux_model  # because at first the flux is in log10
     return flux_model