diff --git a/nanovna.h b/nanovna.h
index 82cc5cc..27f5723 100644
--- a/nanovna.h
+++ b/nanovna.h
@@ -18,7 +18,7 @@
  */
 #include "ch.h"
 
-//#ifdef TINYSA_F303
+#ifdef TINYSA_F303
 #ifdef TINYSA_F072
 #error "Remove comment for #ifdef TINYSA_F303"
 #endif
@@ -26,7 +26,7 @@
 #define TINYSA4
 #endif
 #define TINYSA4_PROTO
-//#endif
+#endif
 
 #ifdef TINYSA_F072
 #ifdef TINYSA_F303
@@ -583,8 +583,11 @@ extern uint16_t graph_bottom;
 #define MENU_BUTTON_HEIGHT_N(n)   (LCD_HEIGHT/(n)-1)
 
 // Define message box width
+#ifdef TINYSA4
+#define MESSAGE_BOX_WIDTH     300
+#else
 #define MESSAGE_BOX_WIDTH     180
-
+#endif
 // Form button (at center screen better be less LCD_WIDTH - 2*OFFSETX)
 #define MENU_FORM_WIDTH    (LCD_WIDTH - 2*OFFSETX)
 
diff --git a/sa_core.c b/sa_core.c
index 981597e..ec2b039 100644
--- a/sa_core.c
+++ b/sa_core.c
@@ -5296,7 +5296,7 @@ static volatile int dummy;
   peakLevel = -170;
   temp_min_level = 100;
   for (int t=(in_selftest? 0 : TRACES_MAX-1); t >= 0; t--) {        // During selftest only trace 0 is used.
-    if (IS_TRACE_ENABLE(t) && !(ignore_stored && (t == TRACE_STORED))) {
+    if (IS_TRACE_ENABLE(t) && !(ignore_stored && (t == TRACE_STORED))) {  // Selftest 0 1 switches off in_selftest so ignore stored trace
       float *trace_data = measured[t];
       for (int i=0;i<sweep_points; i++) {
         add_to_peak_finding(trace_data, i);
@@ -7214,6 +7214,8 @@ abort:
 void reset_calibration(void)
 {
   config.is_calibrated = false;
+  config.low_level_offset = 100;
+  config.low_level_output_offset = 100;
 }
 
 void calibrate_modulation(int modulation, int8_t *correction)
diff --git a/ui_sa.c b/ui_sa.c
index 4325371..7cd747d 100644
--- a/ui_sa.c
+++ b/ui_sa.c
@@ -572,6 +572,26 @@ static const menuitem_t  menu_lowoutput_settings[];
 extern bool dirty;
 char range_text[20];
 
+#ifdef TINYSA4
+int input_is_calibrated(void)
+{
+  if (config.low_level_offset != 100)
+    return true;
+  drawMessageBox("Error", "First calibrate 100kHz to 5.34GHz input", 2000);
+  redraw_request|= REDRAW_AREA;
+  return false;
+}
+
+int output_is_calibrated(void)
+{
+  if (config.low_level_output_offset != 100)
+    return true;
+  drawMessageBox("Error", "First calibrate 30MHz output", 2000);
+  redraw_request|= REDRAW_AREA;
+  return false;
+}
+#endif
+
 static UI_FUNCTION_ADV_CALLBACK(menu_sweep_acb)
 {
   (void)data;
@@ -703,7 +723,7 @@ static UI_FUNCTION_CALLBACK(menu_input_curve_prepare_cb)
 {
   (void)item;
   (void)data;
-  if (!config.is_calibrated)
+  if (!input_is_calibrated())
     return;
   kp_help_text = "Enter actual input level";
   kp_buf[0]=0;
@@ -719,7 +739,7 @@ static UI_FUNCTION_CALLBACK(menu_lna_curve_prepare_cb)
 {
   (void)item;
   (void)data;
-  if (!config.is_calibrated)
+  if (!input_is_calibrated())
     return;
   kp_help_text = "Enter actual input level";
   kp_buf[0]=0;
@@ -735,7 +755,7 @@ static UI_FUNCTION_CALLBACK(menu_lna_u_curve_prepare_cb)
 {
   (void)item;
   (void)data;
-  if (!config.is_calibrated)
+  if (!input_is_calibrated())
     return;
   kp_help_text = "Enter actual input level";
   kp_buf[0]=0;
@@ -751,7 +771,7 @@ static UI_FUNCTION_CALLBACK(menu_ultra_curve_prepare_cb)
 {
   (void)item;
   (void)data;
-  if (!config.is_calibrated)
+  if (!input_is_calibrated())
     return;
   kp_help_text = "Enter actual input level";
   kp_buf[0]=0;
@@ -767,11 +787,8 @@ static UI_FUNCTION_CALLBACK(menu_output_curve_prepare_cb)
 {
   (void)item;
   (void)data;
-  if (config.low_level_output_offset == 100) {
-    drawMessageBox("Error", "First set OUTPUT LEVEL", 2000);
-    redraw_request|= REDRAW_AREA;
+  if (!output_is_calibrated())
     return;
-  }
   current_curve = CORRECTION_LOW_OUT;
   menu_push_submenu(menu_curve);
 }
@@ -821,6 +838,8 @@ static UI_FUNCTION_ADV_CALLBACK(menu_output_level2_acb)
   if (b){
     return;
   }
+  if (!output_is_calibrated())
+    return;
   int old_m = setting.mode;
   reset_settings(M_GENLOW);
   set_level(-30);
@@ -849,6 +868,8 @@ static UI_FUNCTION_ADV_CALLBACK(menu_output_level3_acb)
   if (b){
     return;
   }
+  if (!output_is_calibrated())
+    return;
   int old_m = setting.mode;
   reset_settings(M_GENLOW);
 
@@ -1014,6 +1035,8 @@ static UI_FUNCTION_CALLBACK(menu_calibrate_cb)
     break;
 #ifdef TINYSA4
   case 3:
+    if (!input_is_calibrated())
+      return;
     sweep_mode = SWEEP_CALIBRATE_HARMONIC;
     menu_move_back(false);
     menu_move_back(true);
@@ -3117,7 +3140,7 @@ static const menuitem_t menu_settings[] =
 #ifdef TINYSA4
   { MT_ADV_CALLBACK,0,              "PROGRESS\nBAR",        menu_progress_bar_acb},
   { MT_KEYPAD,      KM_FREQ_CORR,   "FREQ CORR\n\b%s",      "Enter ppb correction"},
-  { MT_SUBMENU,     0,              "CALIBRATE\nHARMONIC",  menu_calibrate_harmonic},
+//  { MT_SUBMENU,     0,              "CALIBRATE\nHARMONIC",  menu_calibrate_harmonic},
 #endif
 #ifdef __NOISE_FIGURE__
   { MT_KEYPAD,      KM_NF,          "NF\n\b%s",             "Enter tinySA noise figure"},