diff --git a/src/wspr.c b/src/wspr.c
--- a/src/wspr.c
+++ b/src/wspr.c
@@ -5,6 +5,7 @@
 #include "wspr.h"
 #include "i2c.h"
 #include "gps.h"
+#include "adc.h"
 #include "config.h"
 
 
@@ -304,3 +305,58 @@ void wspr_transmit(uint8_t* grid_locator
 
 }
 
+
+// Transmit boot-up test tones to check tx
+void wspr_pilot_tone(void)
+{
+	// Bring up TCXO
+    HAL_GPIO_WritePin(OSC_NOTEN, 0);
+    HAL_GPIO_WritePin(TCXO_EN, 1);
+    HAL_Delay(100);
+
+    // Bring up the chip
+    i2c_init();
+    si5351_init(i2c_get(), SI5351_CRYSTAL_LOAD_8PF, 0);
+    si5351_set_correction(0);
+    si5351_set_freq(WSPR_DEFAULT_FREQ * 100, 0, SI5351_CLK0);
+    si5351_drive_strength(SI5351_CLK0, SI5351_DRIVE_6MA); // Set for max power if desired (8ma max)
+    si5351_output_enable(SI5351_CLK0, 1);
+
+    // Make sure the other outputs of the SI5351 are disabled
+    si5351_output_enable(SI5351_CLK1, 0); // Disable the clock initially
+    si5351_output_enable(SI5351_CLK2, 0); // Disable the clock initially
+
+    // disable clock powers
+    si5351_set_clock_pwr(SI5351_CLK1, 0);
+    si5351_set_clock_pwr(SI5351_CLK2, 0);
+
+    // Key transmitter
+    si5351_output_enable(SI5351_CLK0, 1);
+
+    uint8_t tone_table[7] = {50, 100, 70, 50, 0, 10, 0};
+
+    // Boot-up pilot tones
+    for(uint8_t i=0; i<7; i++)
+    {
+        uint32_t freq2 = (WSPR_DEFAULT_FREQ + 10*tone_table[i]) * 100;
+        si5351_set_freq(freq2, 0, SI5351_CLK0);
+		#ifndef LED_DISABLE
+        	HAL_GPIO_TogglePin(LED_BLUE);
+		#endif
+        HAL_Delay(500);
+    }
+
+
+    // Disable transmitter
+    si5351_output_enable(SI5351_CLK0, 0);
+
+    HAL_GPIO_WritePin(OSC_NOTEN, 1);
+    HAL_GPIO_WritePin(TCXO_EN, 0);
+
+    i2c_deinit();
+
+    // Make sure LED is off if we had an odd number of toggles above
+	HAL_GPIO_WritePin(LED_BLUE, 0);
+
+}
+