diff --git a/dev/cc1200/cc1200-conf.h b/dev/cc1200/cc1200-conf.h
index 3641e87e3..1e50cc828 100644
--- a/dev/cc1200/cc1200-conf.h
+++ b/dev/cc1200/cc1200-conf.h
@@ -73,15 +73,15 @@
 #define CC1200_MAX_PAYLOAD_LEN           127
 #endif
 /*---------------------------------------------------------------------------*/
-/* 
+/*
  * The RX watchdog is used to check whether the radio is in RX mode at regular
  * intervals (once per second). Can be used to improve reliability especially
- * if NullRDC is used. Turned of by default. 
- */ 
+ * if NullRDC is used. Turned of by default.
+ */
 #ifdef CC1200_CONF_USE_RX_WATCHDOG
-#define CC1200_USE_RX_WATCHDOG CC1200_CONF_USE_RX_WATCHDOG
+#define CC1200_USE_RX_WATCHDOG          CC1200_CONF_USE_RX_WATCHDOG
 #else
-#define CC1200_USE_RX_WATCHDOG 0 
+#define CC1200_USE_RX_WATCHDOG          0
 #endif
 /*---------------------------------------------------------------------------*/
 /*
@@ -159,9 +159,7 @@
 #define CC1200_DEFAULT_CHANNEL          CC1200_CONF_DEFAULT_CHANNEL
 #else
 /* 868.325 MHz */
-//#define CC1200_DEFAULT_CHANNEL      26
-/* 865.725 MHz */
-#define CC1200_DEFAULT_CHANNEL          13
+#define CC1200_DEFAULT_CHANNEL          26
 #endif
 /*---------------------------------------------------------------------------*/
 /*
@@ -182,11 +180,19 @@
 #endif
 /*---------------------------------------------------------------------------*/
 /*
- * If CC1200_AUTOCAL is 0, a timeout is used to decide when to calibrate when
- * going to TX.
+ * If CC1200_AUTOCAL is not set, we use this parameter to defer 
+ * calibration until a certain amount of time has expired. 
  *
- * Therefore, we don't calibrate every time we transmit. Set this parameter
- * to 0 when this feature is not used.
+ * This is what happens in detail:
+ *
+ * - We (manually) calibrate once after initialization
+ * - We (manually) calibrate every time we change the channel
+ * - We (manually) calibrate when the radio is turned on() only if
+ *   the timeout has expired
+ * - We (manually) calibrate when transmitting only of the timeout has expired
+ * 
+ * Set this parameter to 0 when this feature is not used. In this case we 
+ * (manually) calibrate in all situations mentioned above.
  */
 #ifdef CC1200_CONF_CAL_TIMEOUT_SECONDS
 #define CC1200_CAL_TIMEOUT_SECONDS      CC1200_CONF_CAL_TIMEOUT_SECONDS
diff --git a/dev/cc1200/cc1200.c b/dev/cc1200/cc1200.c
index 0ba4eccef..1f3bfd499 100644
--- a/dev/cc1200/cc1200.c
+++ b/dev/cc1200/cc1200.c
@@ -57,7 +57,6 @@
  * - 3: Print errors + warnings + information (what's going on...)
  */
 #define DEBUG_LEVEL                     2
-
 /*
  * RF test mode. Blocks inside "configure()".
  * - Set this parameter to 1 in order to produce an modulated carrier (PN9)
@@ -68,6 +67,7 @@
 #ifndef CC1200_RF_TESTMODE
 #define CC1200_RF_TESTMODE              0
 #endif
+
 #if CC1200_RF_TESTMODE
 #undef CC1200_RF_CFG
 #if CC1200_RF_TESTMODE == 1
@@ -248,6 +248,12 @@ extern const cc1200_rf_cfg_t CC1200_RF_CFG;
 #define RF_UPDATE_CHANNEL               0x10
 /* SPI was locked when calling RX interrupt, let the pollhandler do the job */
 #define RF_POLL_RX_INTERRUPT            0x20
+/* Force calibration in case we don't use CC1200 AUTOCAL + timeout */
+#if !CC1200_AUTOCAL
+#if CC1200_CAL_TIMEOUT_SECONDS
+#define RF_FORCE_CALIBRATION            0x40
+#endif
+#endif
 /*---------------------------------------------------------------------------*/
 /* Length of 802.15.4 ACK. We discard packets with a smaller size */
 #define ACK_LEN                         3
@@ -403,10 +409,10 @@ static uint8_t rf_flags = 0;
 /* Use a timeout to decide when to calibrate */
 static unsigned long cal_timer;
 #endif
-#if USE_RX_WATCHDOG
+#if CC1200_USE_RX_WATCHDOG
 /* Timer used for RX watchdog */
 static struct etimer et;
-#endif
+#endif /* #if CC1200_USE_RX_WATCHDOG */
 /*---------------------------------------------------------------------------*/
 /* Prototypes for Netstack API radio driver functions */
 /*---------------------------------------------------------------------------*/
@@ -557,15 +563,15 @@ PROCESS_THREAD(cc1200_process, ev, data)
 
   PROCESS_BEGIN();
 
-#if USE_RX_WATCHDOG && !CC1200_SNIFFER
+#if CC1200_USE_RX_WATCHDOG && !CC1200_SNIFFER
   /* RX watchdog interferes with sniffer. Reason unknown... */
   while(1) {
 
-    PROCESS_WAIT_EVENT_UNTIL(etimer_expired(&et));
-    etimer_reset(&et);
-
     if((rf_flags & (RF_ON | RF_TX_ACTIVE)) == RF_ON) {
 
+      PROCESS_WAIT_EVENT_UNTIL(etimer_expired(&et));
+      etimer_reset(&et);
+
       /*
        * We are on and not in TX. As every function of this driver
        * assures that we are in RX mode
@@ -593,10 +599,12 @@ PROCESS_THREAD(cc1200_process, ev, data)
 
       }
 
+    } else {
+      PROCESS_YIELD();
     }
 
   }
-#endif /* #if USE_RX_WATCHDOG */
+#endif /* #if CC1200_USE_RX_WATCHDOG */
 
   PROCESS_YIELD_UNTIL(ev == PROCESS_EVENT_EXIT);
 
@@ -689,19 +697,18 @@ init(void)
 
     RELEASE_SPI();
 
-    /* Set default channel */
+    /* Set default channel. This will also force initial calibration! */
     set_channel(CC1200_DEFAULT_CHANNEL);
 
     /*
      * We have to call off() before on() because on() relies on the
-     * configuration of the GPIO0 pin (even if we turn the radio on in
-     * sniffer mode afterwards)
+     * configuration of the GPIO0 pin
      */
     off();
 
-#if CC1200_SNIFFER
-    on();
-#endif
+/* #if CC1200_SNIFFER */
+/*     on(); */
+/* #endif */
 
   }
 
@@ -787,14 +794,7 @@ transmit(unsigned short transmit_len)
 #if !CC1200_AUTOCAL
   /* Perform manual calibration unless just turned on */
   if(!was_off) {
-#if CC1200_CAL_TIMEOUT_SECONDS
-    /* Calibrate after a delay defined by CC1200_CAL_TIMEOUT_SECONDS */
-    if((clock_seconds() - cal_timer) > CC1200_CAL_TIMEOUT_SECONDS) {
-      calibrate();
-    }
-#else
     calibrate();
-#endif
   }
 #endif
 
@@ -824,6 +824,9 @@ transmit(unsigned short transmit_len)
 
     ret = RADIO_TX_ERR;
     if(!was_off) {
+#ifdef RF_FORCE_CALIBRATION
+      rf_flags |= RF_FORCE_CALIBRATION;
+#endif
       idle_calibrate_rx();
     }
   }
@@ -1059,9 +1062,11 @@ on(void)
 
     RELEASE_SPI();
 
-#if USE_RX_WATCHDOG
+#if CC1200_USE_RX_WATCHDOG
+    PROCESS_CONTEXT_BEGIN(&cc1200_process);
     etimer_set(&et, CLOCK_SECOND);
-#endif
+    PROCESS_CONTEXT_END(&cc1200_process);
+#endif /* #if CC1200_USE_RX_WATCHDOG */
 
   } else {
     INFO("RF: Already on\n");
@@ -1103,9 +1108,9 @@ off(void)
 
     RELEASE_SPI();
 
-#if USE_RX_WATCHDOG
+#if CC1200_USE_RX_WATCHDOG
     etimer_stop(&et);
-#endif
+#endif /* #if CC1200_USE_RX_WATCHDOG */
 
   } else {
     INFO("RF: Already off\n");
@@ -1664,6 +1669,15 @@ static void
 calibrate(void)
 {
 
+#ifdef RF_FORCE_CALIBRATION
+  if (!(rf_flags & RF_FORCE_CALIBRATION) 
+      && ((clock_seconds() - cal_timer) < CC1200_CAL_TIMEOUT_SECONDS)) {
+    /* Timeout not reached, defer calibration... */
+    return;
+  }
+  rf_flags &= ~RF_FORCE_CALIBRATION;
+#endif
+
   INFO("RF: Calibrate\n");
 
   strobe(CC1200_SCAL);
@@ -1738,11 +1752,7 @@ rx_rx(void)
 
   uint8_t s = state();
 
-  if(s == STATE_RX) {
-    /* Already in RX. Flush RX FIFO */
-    single_write(CC1200_RXFIRST,
-                 single_read(CC1200_RXLAST));
-  } else if(s == STATE_IDLE) {
+  if(s == STATE_IDLE) {
     /* Proceed to rx */
   } else if(s == STATE_RX_FIFO_ERR) {
     WARNING("RF: RX FIFO error!\n");
@@ -1762,11 +1772,9 @@ rx_rx(void)
   /* Clear pending GPIO interrupts */
   ENABLE_GPIO_INTERRUPTS();
 
-  if(s != STATE_RX) {
-    strobe(CC1200_SFRX);
-    strobe(CC1200_SRX);
-    BUSYWAIT_UNTIL_STATE(STATE_RX, RTIMER_SECOND / 100);
-  }
+  strobe(CC1200_SFRX);
+  strobe(CC1200_SRX);
+  BUSYWAIT_UNTIL_STATE(STATE_RX, RTIMER_SECOND / 100);
 
 }
 /*---------------------------------------------------------------------------*/
@@ -2083,6 +2091,9 @@ set_channel(uint8_t channel)
 
   /* Turn on RX again unless we turn off anyway */
   if(!was_off) {
+#ifdef RF_FORCE_CALIBRATION
+    rf_flags |= RF_FORCE_CALIBRATION;
+#endif
     idle_calibrate_rx();
   }