diff --git a/nanovna.h b/nanovna.h
index 647fa53..4f84bd0 100644
--- a/nanovna.h
+++ b/nanovna.h
@@ -1190,6 +1190,7 @@ void clear_all_config_prop_data(void);
 extern void ui_init(void);
 extern void ui_process(void);
 int current_menu_is_form(void);
+extern float nf_gain;
 
 void ui_mode_normal(void);
 void ui_mode_menu(void);
diff --git a/plot.c b/plot.c
index 83bd992..5a63cec 100644
--- a/plot.c
+++ b/plot.c
@@ -1602,10 +1602,10 @@ static void cell_draw_marker_info(int x0, int y0)
       aNP = marker_to_value(0);
 #endif
       float mNF = aNP -  logf(actual_rbw_x10*100.0) * (10.0/logf(10.0)) + 173.93 + SI4463_noise_correction_x10/10.0;   // measured noise figure at 20C
-      if (setting.external_gain != 0) {
-        float mnf = expf(mNF/10 * logf(10));     // measure noise factor
+      if (nf_gain != 0) {
+        float mnf = expf((mNF - nf_gain)/10 * logf(10));     // measure noise factor
         float tnf = expf(config.noise_figure/10 * logf(10));     // tinySA noise factor
-        float amp_gain = expf(setting.external_gain/10 * logf(10));
+        float amp_gain = expf(nf_gain/10 * logf(10));
         float anf = mnf - (tnf - 1.0)/amp_gain;
         mNF = 10*logf(anf)/logf(10);
       }
@@ -1617,7 +1617,7 @@ static void cell_draw_marker_info(int x0, int y0)
 //        j = 1;
       int xpos = 1 + (j%2)*(WIDTH/2) + CELLOFFSETX - x0;
       int ypos = 1 + (j/2)*(16) - y0;
-      cell_printf(xpos, ypos, FONT_b"NF: %4.1f", mNF);
+      cell_printf(xpos, ypos, FONT_b"GAIN: %4.1fdB   NF: %4.1f", nf_gain, mNF);
       break;
 #endif
     } else
diff --git a/sa_core.c b/sa_core.c
index c73c695..a401b37 100644
--- a/sa_core.c
+++ b/sa_core.c
@@ -4780,7 +4780,7 @@ enum {
 
 #ifdef TINYSA4
 //#define CAL_LEVEL   -23.5
-#define CAL_LEVEL   -23
+#define CAL_LEVEL   -23.1
 #else
 #define CAL_LEVEL   (has_esd ? -26.2 : -25)
 #endif
@@ -4833,8 +4833,8 @@ const test_case_t test_case [] =
 #define TEST_SPUR    23
  TEST_CASE_STRUCT(TC_BELOW,      TP_SILENT,     144,     8,      -95,    0,     0),       // 22 Measure 48MHz spur
 #define TEST_LEVEL  24
- TEST_CASE_STRUCT(TC_LEVEL,   TP_30MHZ,       30,     0,      CAL_LEVEL,   145,     -55),      // 23 Measure level
- TEST_CASE_STRUCT(TC_LEVEL,   TP_30MHZ_LNA,   30,     0,      CAL_LEVEL,   145,     -55),      // 23 Measure level
+ TEST_CASE_STRUCT(TC_LEVEL,   TP_30MHZ,       30.01,     0,      CAL_LEVEL,   145,     -55),      // 23 Measure level
+ TEST_CASE_STRUCT(TC_LEVEL,   TP_30MHZ_LNA,   30.01,     0,      CAL_LEVEL,   145,     -55),      // 23 Measure level
  TEST_CASE_STRUCT(TC_LEVEL,   TPH_30MHZ,      150,     0,      CAL_LEVEL-30,   145,     -55),      // 23 Measure level
 
 };
diff --git a/si4468.c b/si4468.c
index cca7a1a..8da173b 100644
--- a/si4468.c
+++ b/si4468.c
@@ -1524,14 +1524,14 @@ static const RBW_t RBW_choices[] =
 {
 // BW register    corr  freq
  {SI4463_RBW_02kHz, 18,3,42},
- {SI4463_RBW_1kHz,  18,10,22},
- {SI4463_RBW_3kHz,  12,30,21},
- {SI4463_RBW_10kHz, 7,100,20},
- {SI4463_RBW_30kHz, 10,300,20},
- {SI4463_RBW_100kHz,2,1000,26},
- {SI4463_RBW_300kHz,2,3000,19},
- {SI4463_RBW_600kHz,3,6000,18},
- {SI4463_RBW_850kHz,12,8500,15},
+ {SI4463_RBW_1kHz,  18,10,29},
+ {SI4463_RBW_3kHz,  12,30,28},
+ {SI4463_RBW_10kHz, 7,100,26},
+ {SI4463_RBW_30kHz, 10,300,22},
+ {SI4463_RBW_100kHz,2,1000,19},
+ {SI4463_RBW_300kHz,2,3000,7},
+ {SI4463_RBW_600kHz,3,6000,-1},
+ {SI4463_RBW_850kHz,12,8500,-9},
 };
 
 const uint8_t SI4432_RBW_count = ((int)(sizeof(RBW_choices)/sizeof(RBW_t)));
diff --git a/ui_sa.c b/ui_sa.c
index 4e48454..23c9c30 100644
--- a/ui_sa.c
+++ b/ui_sa.c
@@ -1151,6 +1151,7 @@ static UI_FUNCTION_CALLBACK(menu_clearconfig_cb)
   ui_mode_normal();
 }
 
+float nf_gain;
 const char * const averageText[] = { "OFF", "MIN", "MAX", "MAXD", " A 4", "A 16", "AVER", "QUASI", "DECONV"};
 
 static UI_FUNCTION_ADV_CALLBACK(menu_measure_acb)
@@ -1348,13 +1349,17 @@ static UI_FUNCTION_ADV_CALLBACK(menu_measure_acb)
       markers[0].mtype = M_NOISE;          // Not tracking
       set_extra_lna(true);
       kp_help_text = "Amplifier Gain ";
+      float old_gain = setting.external_gain;
       ui_mode_keypad(KM_EXT_GAIN);
-      kp_help_text = "Noise frequency";
+      nf_gain = setting.external_gain;
+      setting.external_gain = old_gain;
+      kp_help_text = "Noise center frequency";
       ui_mode_keypad(KM_CENTER);
       set_marker_frequency(0, uistat.value);
-//      kp_help_text = "Noise width";
-//      ui_mode_keypad(KM_SPAN);
-      set_sweep_frequency(ST_SPAN, 0);
+      kp_help_text = "Noise span";
+      ui_mode_keypad(KM_SPAN);
+      set_RBW(get_sweep_frequency(ST_SPAN)/100 / 100);
+//      set_sweep_frequency(ST_SPAN, 0);
       set_average(AV_100);
       break;
 #endif