diff --git a/artiq/frontend/artiq_sinara_tester.py b/artiq/frontend/artiq_sinara_tester.py
index b6869b7d8..a92eb949c 100755
--- a/artiq/frontend/artiq_sinara_tester.py
+++ b/artiq/frontend/artiq_sinara_tester.py
@@ -329,7 +329,7 @@ class SinaraTester(EnvExperiment):
             for channel_n, (channel_name, channel_dev) in enumerate(channels):
                 frequency = 10*(card_n + 1) + channel_n
                 print("{}\t{}MHz".format(channel_name, frequency))
-                self.setup_urukul(channel_dev, frequency)
+                self.setup_urukul(channel_dev, float(frequency))
         print("Press ENTER when done.")
         input()