diff --git a/test/simulation/106-refclock b/test/simulation/106-refclock
index c22cd42..5c5794c 100755
--- a/test/simulation/106-refclock
+++ b/test/simulation/106-refclock
@@ -9,19 +9,22 @@ refclock_jitter=$jitter
 min_sync_time=45
 max_sync_time=70
 chronyc_start=70
-client_conf="refclock SHM 0 stratum 3 delay 1e-3 refid GPS"
 chronyc_conf="tracking"
 
-run_test || test_fail
-check_chronyd_exit || test_fail
-check_source_selection || test_fail
-check_sync || test_fail
-check_chronyc_output "^Reference ID.*47505300 \(GPS\)
+for refclock in "SHM 0" "PHC /dev/ptp0"; do
+	client_conf="refclock $refclock stratum 3 delay 1e-3 refid GPS"
+
+	run_test || test_fail
+	check_chronyd_exit || test_fail
+	check_source_selection || test_fail
+	check_sync || test_fail
+	check_chronyc_output "^Reference ID.*47505300 \(GPS\)
 Stratum.*: 4
 .*
 Root delay      : 0.001000000 seconds
 .*
 Update interval : 16\.. seconds
 .*$" || test_fail
+done
 
 test_pass