diff --git a/src/sim/Controller_BL0942.cpp b/src/sim/Controller_BL0942.cpp
index d06e102bd..372c62ed5 100644
--- a/src/sim/Controller_BL0942.cpp
+++ b/src/sim/Controller_BL0942.cpp
@@ -83,8 +83,9 @@ void CControllerBL0942::saveTo(struct cJSON *j_obj) {
 	cJSON_AddStringToObject(j_obj, "voltage", this->txt_voltage->getText());
 	cJSON_AddStringToObject(j_obj, "current", this->txt_current->getText());
 	cJSON_AddStringToObject(j_obj, "power", this->txt_power->getText());
-	cJSON_AddStringToObject(j_obj, "frequency", this->txt_freq->getText());
-
+	if (this->txt_freq) {
+		cJSON_AddStringToObject(j_obj, "frequency", this->txt_freq->getText());
+	}
 }
 void CControllerBL0942::loadFrom(struct cJSON *j_obj) {
 	cJSON *v = cJSON_GetObjectItemCaseSensitive(j_obj, "voltage");
diff --git a/src/sim/Controller_BL0942.h b/src/sim/Controller_BL0942.h
index dfd7aa9e7..b39783ad6 100644
--- a/src/sim/Controller_BL0942.h
+++ b/src/sim/Controller_BL0942.h
@@ -18,7 +18,7 @@ class CControllerBL0942 : public CControllerBase {
 public:
 	CControllerBL0942() {
 		rx = tx = 0;
-		txt_voltage = txt_current = txt_power = 0;
+		txt_voltage = txt_current = txt_power = txt_freq = 0;
 		realCurrent = 0.25f;
 		realPower = 60.0f;
 		realVoltage = 220.0f;