diff --git a/src/osmo_gsm_tester/obj/ms_srs.py b/src/osmo_gsm_tester/obj/ms_srs.py
index f564519..767f887 100644
--- a/src/osmo_gsm_tester/obj/ms_srs.py
+++ b/src/osmo_gsm_tester/obj/ms_srs.py
@@ -42,6 +42,7 @@
         'tx_gain': schema.INT,
         'rx_gain': schema.INT,
         'freq_offset': schema.INT,
+        'force_ul_amplitude': schema.STR,
         }
     for key, val in RunNode.schema().items():
         resource_schema['run_node.%s' % key] = val