diff --git a/main.c b/main.c
index 7dc8c74..e424911 100644
--- a/main.c
+++ b/main.c
@@ -981,7 +981,8 @@ config_t config = {
   .harmonic_level_offset = 7,
   .shift_level_offset = -0.5,
   .drive1_level_offset = -1,
-  .drive2_level_offset = -1.5,
+  .drive2_level_offset = -2.5,
+  .drive3_level_offset = -3,
   .correction_frequency =
   {
    { 10000, 100000, 1000000, 5000000, 15000000, 30000000, 145000000, 400000000, 720000000, 800000000, 800000001, 1519000000, 1527000000, 3000000000, 3500000000, 4000000000, 4500000000, 5000000000, 5500000000, 6000000000 }, // low in
@@ -1181,7 +1182,7 @@ VNA_SHELL_FUNCTION(cmd_hop)
     int old_vbwSteps = vbwSteps;
 //    vbwSteps = 1;
     for (freq_t f = start; f <= stop; f += step) {
-        if (mask & 1) shell_printf("%Q ", f);
+        if (mask & 1) shell_printf("%U ", f);
         float v = PURE_TO_float(perform(false, 0, f, false));
         if (mask & 2) shell_printf("%f ", v);
         shell_printf("\r\n");
diff --git a/nanovna.h b/nanovna.h
index afd3384..9d84ecb 100644
--- a/nanovna.h
+++ b/nanovna.h
@@ -134,15 +134,18 @@
 #define MAX_LOW_OUTPUT_FREQ ((freq_t)1100000000)
 #define HIGH_MIN_FREQ_MHZ   136// 825
 #define HIGH_MAX_FREQ_MHZ   1130
-#define MINIMUM_DIRECT_FREQ 830000000ULL
-#define ULTRA_MAX_FREQ      5350000000ULL
-#define ULTRA_AUTO  10000000000ULL // 10GHz
+#define MINIMUM_DIRECT_FREQ  830000000ULL
+#define ULTRA_MAX_FREQ      5350000000ULL           // Start of harmonic mode
+#define ULTRA_AUTO         10000000000ULL // 10GHz
 //#define ULTRA_MAX_FREQ      2900000000ULL
 #define MAX_LO_FREQ         4350000000ULL
-#define MAX_ABOVE_IF_FREQ   3350000000ULL
-#define MIN_BELOW_IF_FREQ   2300000000ULL
+#define MAX_ABOVE_IF_FREQ   3350000000ULL           // Range to use for below IF
+#define MIN_BELOW_IF_FREQ   2300000000ULL           // Range to use for below IF
 //#define LOW_MAX_FREQ         800000000ULL
-#define MIN_BELOW_LO         550000000ULL
+#define MIN_BELOW_LO         550000000ULL   // not used????
+#define DRIVE0_MAX_FREQ      600000000ULL            // LO drive 0
+#define DRIVE1_MAX_FREQ     1200000000ULL           // LO drive 1
+#define DRIVE2_MAX_FREQ     2000000000ULL           // LO drive 2
 #ifdef __NEW_SWITCHES__
 #define DIRECT_START config.direct_start
 #define DIRECT_STOP  config.direct_stop
@@ -711,6 +714,7 @@ typedef struct config {
   float shift_level_offset;
   float drive1_level_offset;
   float drive2_level_offset;
+  float drive3_level_offset;
 #endif
 #ifdef __NOISE_FIGURE__
   float noise_figure;
diff --git a/sa_cmd.c b/sa_cmd.c
index 800c516..2b29af0 100644
--- a/sa_cmd.c
+++ b/sa_cmd.c
@@ -338,7 +338,7 @@ VNA_SHELL_FUNCTION(cmd_leveloffset)
 {
   //                                     0    1      2
 #ifdef TINYSA4
-  static const char cmd_mode_list[] = "low|high|switch|receive_switch|lna|harmonic|shift|drive1|drive2";
+  static const char cmd_mode_list[] = "low|high|switch|receive_switch|lna|harmonic|shift|drive1|drive2|drive3";
 #else
   static const char cmd_mode_list[] = "low|high|switch|receive_switch";
 #endif
@@ -356,6 +356,7 @@ VNA_SHELL_FUNCTION(cmd_leveloffset)
     shell_printf(p, "shift",        config.shift_level_offset);
     shell_printf(p, "drive1",       config.drive1_level_offset);
     shell_printf(p, "drive2",       config.drive2_level_offset);
+    shell_printf(p, "drive3",       config.drive3_level_offset);
 #endif
     return;
   }
@@ -378,6 +379,7 @@ VNA_SHELL_FUNCTION(cmd_leveloffset)
       case 6: config.shift_level_offset = v; break;
       case 7: config.drive1_level_offset = v; break;
       case 8: config.drive2_level_offset = v; break;
+      case 9: config.drive3_level_offset = v; break;
 #endif
       default: goto usage;
     }
diff --git a/sa_core.c b/sa_core.c
index 02b5087..d18b907 100644
--- a/sa_core.c
+++ b/sa_core.c
@@ -1805,13 +1805,13 @@ pureRSSI_t get_frequency_correction(freq_t f)      // Frequency dependent RSSI c
   if (setting.mode == M_LOW) {
     switch(actual_drive) {
     case 1:
-      cv += float_TO_PURE_RSSI(-1);
+      cv += float_TO_PURE_RSSI(config.drive1_level_offset);
       break;
     case 2:
-      cv += float_TO_PURE_RSSI(-1.5);
+      cv += float_TO_PURE_RSSI(config.drive2_level_offset);
       break;
     case 3:
-      cv += float_TO_PURE_RSSI(-2);
+      cv += float_TO_PURE_RSSI(config.drive3_level_offset);
       break;
     }
     if (ultra && f > ultra_threshold) {
@@ -3812,11 +3812,11 @@ again:                                                              // Spur redu
           if (actual_drive & 0x04){     // Automatic mixer drive
             if (LO_harmonic)
               actual_drive = 3;
-            else if (lf <  600000000ULL)       // below 600MHz
+            else if (lf <  DRIVE0_MAX_FREQ)       // below 600MHz
               actual_drive = 0;
-            else if (lf < 1200000000ULL) // below 1.2GHz
+            else if (lf < DRIVE1_MAX_FREQ) // below 1.2GHz
               actual_drive = 1;
-            else if (lf < 2000000000ULL)  // below 2GHz
+            else if (lf < DRIVE2_MAX_FREQ)  // below 2GHz
               actual_drive = 2;
             else
               actual_drive = 3;