diff --git a/firmware/mixertx/mixertx.c b/firmware/mixertx/mixertx.c
index 53ed961a..a1c15c06 100644
--- a/firmware/mixertx/mixertx.c
+++ b/firmware/mixertx/mixertx.c
@@ -66,18 +66,9 @@ int main(void)
 
 	max2837_setup();
 	rffc5071_init();
+	rffc5071_reg_write(RFFC5071_GPO, 0x0001); /* PLL lock output on GPO4 */
 	gpio_set(PORT_LED1_3, (PIN_LED2)); /* LED2 on */
 
-	/* FIXME testing serial reads */
-	while (1) {
-		//rffc5071_init();
-		//rffc5071_reg_write(0x7a, 0xf0ca);
-		if (rffc5071_reg_read(0x00) == 0xbefa)
-			gpio_set(PORT_LED1_3, (PIN_LED3)); /* LED3 on */
-		else
-			gpio_clear(PORT_LED1_3, (PIN_LED3)); /* LED3 off */
-	}
-
 	max2837_set_frequency(freq);
 	max2837_start();
 	max2837_tx();