diff --git a/test_measure_with_ohmpi_card_3_15.py b/test_measure_with_ohmpi_card_3_15.py
index 769f02dda20e9ad5adccb917df652731eb8288a2..50e9d5acd4a96eae04799ddea287a9e0b20a3faf 100644
--- a/test_measure_with_ohmpi_card_3_15.py
+++ b/test_measure_with_ohmpi_card_3_15.py
@@ -5,7 +5,7 @@ change_config('config_ohmpi_card_3_15.py', verbose=False)
 from OhmPi.measure import OhmPiHardware
 
 k = OhmPiHardware()
-k._vab_pulse(vab=12, length=1., sampling_rate=k.tx.sampling_rate, polarity=1)
+k._vab_pulse(vab=12, length=1., sampling_rate=k.rx.sampling_rate, polarity=1)
 r = k.readings[:,2]/k.readings[:,1]
 print(f'Mean resistance: {np.mean(r):.3f} Ohms, Dev. {100*np.std(r)/np.mean(r):.1f} %')
 print(f'sampling rate: {k.rx.sampling_rate:.1f} ms, mean sample spacing: {np.mean(np.diff(k.readings[:,0]))*1000.:.1f} ms')