diff --git a/sa_core.c b/sa_core.c
index 3874eca..b933732 100644
--- a/sa_core.c
+++ b/sa_core.c
@@ -5917,6 +5917,8 @@ const test_case_t test_case [] =
  TEST_CASE_STRUCT(TC_MEASURE,   TP_SILENT,       201,     1,      -166,    10,     -166),      // 16 Measure RBW step time
 #define TEST_JUMP 29
  TEST_CASE_STRUCT(TC_JUMP,      TP_30MHZ_LNA,   30,     0.001,      -40,    0,     CAL_LEVEL),      // 16 Measure jumps
+#define TEST_JUMP_HARMONIC 30
+ TEST_CASE_STRUCT(TC_JUMP,      TP_30MHZ,       30,     0.001,      -40,    0,     CAL_LEVEL),      // 16 Measure jumps
 };
 #else
 {//               Condition     Preparation     Center  Span    Pass    Width(%)Stop
@@ -5991,6 +5993,7 @@ static void test_acquire(int i)
   TRACE_ENABLE(TRACE_STORED_FLAG);
   plot_into_index(measured);
   redraw_request |= REDRAW_CELLS | REDRAW_FREQUENCY;
+//  draw_all(TRUE);
 }
 
 int cell_printf(int16_t x, int16_t y, const char *fmt, ...);
@@ -7264,16 +7267,21 @@ void calibrate_harmonic(void)
   {
     test_freq = jump_freqs[i];
     set_jump_config(i, -2);
-    test_prepare(TEST_JUMP);
+    test_prepare(TEST_JUMP_HARMONIC);
     set_RBW(1000);
 //    set_auto_reflevel(true);
     set_reflevel(-20);
     setting.repeat = 10;
-    test_acquire(TEST_JUMP);                        // Acquire test
+    test_acquire(TEST_JUMP_HARMONIC);                        // Acquire test
+    if (peakLevel < -50) {
+      ili9341_set_foreground(LCD_BRIGHT_COLOR_RED);
+      ili9341_drawstring_7x13("Signal level too low", 30, 200);
+      goto quit;
+    }
     set_jump_config(i, get_jump_config(i) + measure_jump(i));
     calibration_busy();
     chThdSleepMilliseconds(500);
-    test_acquire(TEST_JUMP);                        // Acquire test
+    test_acquire(TEST_JUMP_HARMONIC);                        // Acquire test
     set_jump_config(i, get_jump_config(i) + measure_jump(i));
     calibration_busy();
     chThdSleepMilliseconds(500);
@@ -7285,6 +7293,7 @@ void calibrate_harmonic(void)
   config_save();
   ili9341_set_foreground(LCD_BRIGHT_COLOR_GREEN);
   ili9341_drawstring_7x13("Calibration complete", 40, 200);
+  quit:
   ili9341_drawstring_7x13("Touch screen to continue", 40, 220);
   wait_user();
   ili9341_clear_screen();
diff --git a/ui_sa.c b/ui_sa.c
index 86e538e..c3e1d11 100644
--- a/ui_sa.c
+++ b/ui_sa.c
@@ -927,7 +927,8 @@ static UI_FUNCTION_CALLBACK(menu_scale_cb)
 static UI_FUNCTION_CALLBACK(menu_calibrate_cb)
 {
   (void)data;
-  switch (item) {
+  (void)item;
+  switch (data) {
   case 1:
     sweep_mode = SWEEP_CALIBRATE;
     menu_move_back(true);
@@ -938,6 +939,7 @@ static UI_FUNCTION_CALLBACK(menu_calibrate_cb)
 #ifdef TINYSA4
   case 3:
     sweep_mode = SWEEP_CALIBRATE_HARMONIC;
+    menu_move_back(false);
     menu_move_back(true);
     break;
 #endif
@@ -3089,7 +3091,7 @@ static const menuitem_t menu_calibrate_harmonic[] =
 {
   { MT_FORM | MT_TITLE,      0, "Connect 5.34GHz at -50 to -10dBm",  NULL},
 #ifdef TINYSA4
-  { MT_FORM | MT_CALLBACK,   0, "CALIBRATE",        menu_calibrate_cb},
+  { MT_FORM | MT_CALLBACK,   3, "CALIBRATE",        menu_calibrate_cb},
 #endif
   { MT_FORM | MT_NONE,     0, NULL, menu_back} // next-> menu_back
 };
@@ -3098,8 +3100,8 @@ static const menuitem_t menu_calibrate_harmonic[] =
 static const menuitem_t menu_calibrate[] =
 {
   { MT_FORM | MT_TITLE,      0, "Connect HIGH and LOW",  NULL},
-  { MT_FORM | MT_CALLBACK,   0, "CALIBRATE",                 menu_calibrate_cb},
-  { MT_FORM | MT_CALLBACK,   0, "RESET CALIBRATION",         menu_calibrate_cb},
+  { MT_FORM | MT_CALLBACK,   1, "CALIBRATE",                 menu_calibrate_cb},
+  { MT_FORM | MT_CALLBACK,   2, "RESET CALIBRATION",         menu_calibrate_cb},
 #ifdef TINYSA4
   { MT_FORM | MT_SUBMENU,   0, "CALIBRATE HARMONIC",        menu_calibrate_harmonic},
 #endif