diff --git a/tracker/software/config.c b/tracker/software/config.c
index 2ad2ce0..74ac450 100644
--- a/tracker/software/config.c
+++ b/tracker/software/config.c
@@ -73,13 +73,13 @@ uint8_t ssdv_buffer[256*1024] __attribute__((aligned(32)));
  * (required)							There are possible options:
  * 										- TEL_SATS		GPS Satellites
  * 										- TEL_TTFF		Time to first fix (amount of seconds which it needed to aquire a GPS fix)
- * 										- TEL_VBAT		Battery voltage
- * 										- TEL_VSOL		Solar voltage
+ * 										- TEL_VBAT		Battery voltage (in mV)
+ * 										- TEL_VSOL		Solar voltage (in mV)
  * 										- TEL_PBAT		Battery power (positive charge, negative discharge)
- * 										- TEL_ISOL		Solar short current (works only if USB is unattached)
- * 										- TEL_PRESS		Air pressure (by BME280)
- * 										- TEL_TEMP		Air temperature (by BME280)
- * 										- TEL_HUM		Air humidity (by BME280)
+ * 										- TEL_RBAT		Battery impedance (in mOhm)
+ * 										- TEL_PRESS		Air pressure (in Pa)
+ * 										- TEL_TEMP		Air temperature (in degC*100)
+ * 										- TEL_HUM		Air humidity (in %*10)
  *
  * aprs_conf.tel_enc	bool			The telemetry in the position packets do only contain the raw values. Receivers (like aprs.fi) dont know what these
  * (default false)						values stands for. So we must tell them (e.g. that value 1 is air pressure measured in Pascal). If set to true, the
@@ -184,8 +184,8 @@ void start_user_modules(void)
 	config[0].aprs_conf.preamble = 300;						// APRS Preamble
 	config[0].aprs_conf.tel[0] = TEL_VBAT;					// APRS Telemetry parameter 1
 	config[0].aprs_conf.tel[1] = TEL_PBAT;					// APRS Telemetry parameter 2
-	config[0].aprs_conf.tel[2] = TEL_TEMP;					// APRS Telemetry parameter 3
-	config[0].aprs_conf.tel[3] = TEL_PRESS;					// APRS Telemetry parameter 4
+	config[0].aprs_conf.tel[2] = TEL_RBAT;					// APRS Telemetry parameter 3
+	config[0].aprs_conf.tel[3] = TEL_TEMP;					// APRS Telemetry parameter 4
 	config[0].aprs_conf.tel[4] = TEL_HUM;					// APRS Telemetry parameter 5
 	config[0].aprs_conf.tel_enc = TRUE;						// Transmit Telemetry encoding information activated
 	config[0].aprs_conf.tel_enc_cycle = 3600;				// Transmit Telemetry encoding information every 3600sec
@@ -248,7 +248,7 @@ void start_user_modules(void)
 	chsnprintf(config[3].ssdv_conf.callsign, 7, "DL7AD");	// SSDV Callsign
 	config[3].ssdv_conf.ram_buffer = ssdv_buffer;			// Camera buffer
 	config[3].ssdv_conf.ram_size = sizeof(ssdv_buffer);		// Buffer size
-	config[3].ssdv_conf.res = RES_QVGA;						// Resolution VGA
+	config[3].ssdv_conf.res = RES_QVGA;						// Resolution QVGA
 	config[3].ssdv_conf.redundantTx = true;					// Transmit packets twice
 	//start_image_thread(&config[3]);
 
@@ -282,7 +282,7 @@ void start_user_modules(void)
 	chsnprintf(config[5].ssdv_conf.callsign, 7, "DL7AD2");	// SSDV Callsign
 	config[5].ssdv_conf.ram_buffer = ssdv_buffer;			// Camera buffer
 	config[5].ssdv_conf.ram_size = sizeof(ssdv_buffer);		// Buffer size
-	config[5].ssdv_conf.res = RES_QVGA;						// Resolution XGA
+	config[5].ssdv_conf.res = RES_VGA;						// Resolution XGA
 	//config[5].ssdv_conf.redundantTx = true;					// Transmit packets twice
 	//start_image_thread(&config[5]);
 
diff --git a/tracker/software/config.h b/tracker/software/config.h
index a998cce..5db3fb6 100644
--- a/tracker/software/config.h
+++ b/tracker/software/config.h
@@ -21,7 +21,7 @@
 #define TRACE_TIME				TRUE		/* Enables time tracing on debugging port */
 #define TRACE_FILE				FALSE		/* Enables file and line tracing on debugging port */
 
-#define RUN_3V					FALSE		/* Lets the tracker run a 3V otherwise 1.8V. 3V is needed to do 20dBm radio output power.
+#define RUN_3V					TRUE		/* Lets the tracker run a 3V otherwise 1.8V. 3V is needed to do 20dBm radio output power.
 											 * With 1.8V only 15dBm can be done. Some serial-USB adapters also need a 3V IO level in
 											 * order to work. However 3V takes a lot of power in idle. You can save energy using 1.8V. */
 
diff --git a/tracker/software/drivers/ov5640.c b/tracker/software/drivers/ov5640.c
index e598d93..1939a1f 100644
--- a/tracker/software/drivers/ov5640.c
+++ b/tracker/software/drivers/ov5640.c
@@ -993,7 +993,7 @@ CH_IRQ_HANDLER(Vector5C) {
 	if (LptimRdy) {
 		// VSYNC handling
 		if(!vsync) {
-			// Increase AHB clock to 6 MHz
+			// Increase AHB clock to 48 MHz
 			uint32_t new = (FLASH->ACR & ~FLASH_ACR_LATENCY_Msk) | FLASH_ACR_LATENCY_3WS;
 			FLASH->ACR = new;
 			while(FLASH->ACR != new);
diff --git a/tracker/software/drivers/pac1720.c b/tracker/software/drivers/pac1720.c
index ca65a20..e0e4622 100644
--- a/tracker/software/drivers/pac1720.c
+++ b/tracker/software/drivers/pac1720.c
@@ -4,6 +4,7 @@
 #include "pi2c.h"
 #include "pac1720.h"
 #include "padc.h"
+#include <stdlib.h>
 
 /* 
  * FSP = FSC * FSV
@@ -19,6 +20,8 @@
 
 static int32_t pac1720_pbat;
 static int32_t pac1720_pbat_counter;
+static int32_t pac1720_rbat;
+static int32_t pac1720_rbat_counter;
 
 int16_t pac1720_getPbat(void) {
 	int32_t fsp = FSV * FSC;
@@ -27,40 +30,18 @@ int16_t pac1720_getPbat(void) {
 
 	if(I2C_read16(PAC1720_ADDRESS, PAC1720_CH2_PWR_RAT_HIGH, (uint16_t*)&val)) {
 		I2C_read8(PAC1720_ADDRESS, PAC1720_CH2_VSENSE_HIGH, &sign);
+		TRACE_DEBUG("%016x %02x", val, sign >> 7);
 		return (sign >> 7 ? -1 : 1) * (val * fsp / 65535);
 	} else {
+		TRACE_DEBUG("bla");
 		return 0; // PAC1720 not available (maybe Vcc too low)
 	}
 }
 
-int16_t pac1720_getIsol(void) {
-	if(isUsbConnected()) // USB not connected
-	{
-		// Short solar cells
-		palClearLine(LINE_SOL_SHORT_EN);
-		chThdSleepMilliseconds(300); // Wait a little bit to measure a correct value
-
-		int16_t val;
-		uint8_t ret = I2C_read16(PAC1720_ADDRESS, PAC1720_CH1_VSENSE_HIGH, (uint16_t*)&val);
-
-		// Unshort solar cells
-		palSetLine(LINE_SOL_SHORT_EN);
-
-		// Calculate solar current
-		if(ret) {
-			val = val < 0 ? 0 : val >> 4; // Current can only flow in one direction (negative values are inaccurate readings)
-			return val * FSC / DENO;
-		} else {
-			return 0; // PAC1720 not available (maybe Vcc too low)
-		}
-	}
-	return 0; // USB connected (we dont want to short USB)
-}
-
 int16_t pac1720_getAvgPbat(void) {
 	// Return current value if time interval too short
 	if(!pac1720_pbat_counter)
-		pac1720_getPbat();
+		return pac1720_getPbat();
 
 	// Calculate average power
 	int16_t ret = pac1720_pbat / pac1720_pbat_counter;
@@ -72,7 +53,7 @@ int16_t pac1720_getAvgPbat(void) {
 	return ret;
 }
 
-uint16_t pac1720_getBatteryVoltage(void) {
+uint16_t pac1720_getVbat(void) {
 	uint16_t val;
 	if(!I2C_read16(PAC1720_ADDRESS, PAC1720_CH2_VSOURCE_HIGH, &val))
 		return 0; // PAC1720 not available (maybe Vcc too low)
@@ -80,7 +61,22 @@ uint16_t pac1720_getBatteryVoltage(void) {
 	return (val >> 5) * 20000 / 0x400;
 }
 
-uint16_t pac1720_getSolarVoltage(void) {
+int16_t pac1720_getAvgRbat(void) {
+	// Return current value if time interval too short
+	if(!pac1720_rbat_counter)
+		return 0;
+
+	// Calculate average power
+	int16_t ret = pac1720_rbat / pac1720_rbat_counter;
+
+	// Reset current measurement
+	pac1720_rbat = 0;
+	pac1720_rbat_counter = 0;
+
+	return ret;
+}
+
+uint16_t pac1720_getVsol(void) {
 	uint16_t val;
 	if(!I2C_read16(PAC1720_ADDRESS, PAC1720_CH1_VSOURCE_HIGH, &val))
 		return 0; // PAC1720 not available (maybe Vcc too low)
@@ -101,12 +97,42 @@ THD_FUNCTION(pac1720_thd, arg)
 {
 	(void)arg;
 
+	uint32_t counter = 0;
+	int32_t u1 = 999999;
+	int32_t p1 = 999999;
+	int32_t u2 = -999999;
+	int32_t p2 = -999999;
 	while(true)
 	{
+		// Sample data
+		int32_t v = pac1720_getVbat();
+		int32_t p = pac1720_getPbat();
+
 		// Measure battery power
-		pac1720_pbat += pac1720_getPbat();
+		pac1720_pbat += p;
 		pac1720_pbat_counter++;
 
+		// Measure battery impedance
+		if(p < p1) {
+			u1 = v;
+			p1 = p;
+		}
+		if(p > p2) {
+			u2 = v;
+			p2 = p;
+		}
+		if(++counter%10 == 0 && abs(p1-p2) > 100 && abs(u1-u2) > 0 && p1*u2 != p2*u1)
+		{
+			int32_t rbat = abs((u1*u2*(u1-u2)) / (p1*u2 - p2*u1));
+			pac1720_rbat += rbat;
+			pac1720_rbat_counter++;
+
+			u1 = 999999;
+			p1 = 999999;
+			u2 = -999999;
+			p2 = -999999;
+		}
+
 		chThdSleepMilliseconds(50);
 	}
 }
@@ -131,3 +157,4 @@ void pac1720_init(void)
 	TRACE_INFO("PAC  > Init PAC1720 continuous measurement");
 	chThdCreateFromHeap(NULL, THD_WORKING_AREA_SIZE(256), "PAC1720", NORMALPRIO, pac1720_thd, NULL);
 }
+
diff --git a/tracker/software/drivers/pac1720.h b/tracker/software/drivers/pac1720.h
index 6707cc5..dd42e84 100644
--- a/tracker/software/drivers/pac1720.h
+++ b/tracker/software/drivers/pac1720.h
@@ -40,9 +40,9 @@
 #define PAC1720_CH2_VSENSE_LIMIT_LOW	0x1C
 
 #define PAC1720_CH1_VSOURCE_LIMIT_HIGH	0x1D
-#define PAC1720_CH2_VSOURCE_LIMIT_HIGH	0x1E	
-#define PAC1720_CH1_VSOURCE_LIMIT_LOW	0x1F	
-#define PAC1720_CH2_VSOURCE_LIMIT_LOW	0x20	
+#define PAC1720_CH2_VSOURCE_LIMIT_HIGH	0x1E
+#define PAC1720_CH1_VSOURCE_LIMIT_LOW	0x1F
+#define PAC1720_CH2_VSOURCE_LIMIT_LOW	0x20
 
 #define PAC1720_PRODUCT_ID				0xFD
 #define PAC1720_MANUFACTURER_ID			0xFE
@@ -53,8 +53,9 @@ void pac1720_init(void);
 int16_t pac1720_getIsol(void);
 int16_t pac1720_getPbat(void);
 int16_t pac1720_getAvgPbat(void);
-uint16_t pac1720_getBatteryVoltage(void);
-uint16_t pac1720_getSolarVoltage(void);
+uint16_t pac1720_getVbat(void);
+int16_t pac1720_getAvgRbat(void);
+uint16_t pac1720_getVsol(void);
 bool pac1720_isAvailable(void);
 
 #endif
diff --git a/tracker/software/drivers/wrapper/padc.c b/tracker/software/drivers/wrapper/padc.c
index e03b4f2..20ccdbf 100644
--- a/tracker/software/drivers/wrapper/padc.c
+++ b/tracker/software/drivers/wrapper/padc.c
@@ -68,15 +68,20 @@ void doConversion(void)
 	deinitADC();
 }
 
-uint16_t getBatteryVoltageMV(void)
+uint16_t getBatteryVoltageMV_STM32(void)
 {
 	doConversion();
-	uint16_t vbat = samples[2] * vcc_ref * DIVIDER_VBAT / 4096;
+	return samples[2] * vcc_ref * DIVIDER_VBAT / 4096;
+}
+
+uint16_t getBatteryVoltageMV(void)
+{
+	uint16_t vbat = getBatteryVoltageMV_STM32();
 
 	// Get voltage from PAC1720 (PAC1720 returns false redings below 2.35V)
 	if(vbat >= 2500)
 	{
-		uint16_t vbat_pac = pac1720_getBatteryVoltage(); // Get value from PAC1720
+		uint16_t vbat_pac = pac1720_getVbat(); // Get value from PAC1720
 		if(vbat_pac) // Apply it if valid
 			vbat = vbat_pac;
 	}
@@ -86,10 +91,12 @@ uint16_t getBatteryVoltageMV(void)
 
 uint16_t getSolarVoltageMV(void)
 {
+	uint16_t vbat = getBatteryVoltageMV_STM32();
+
 	// Get voltage from PAC1720 (PAC1720 returns false redings below 2.35V)
-	if(getBatteryVoltageMV() >= 2500)
+	if(vbat >= 2500)
 	{
-		uint16_t vsol_pac = pac1720_getSolarVoltage(); // Get value from PAC1720
+		uint16_t vsol_pac = pac1720_getVsol(); // Get value from PAC1720
 		if(vsol_pac)
 			return vsol_pac;
 	}
diff --git a/tracker/software/drivers/wrapper/padc.h b/tracker/software/drivers/wrapper/padc.h
index 448e68b..e957d54 100644
--- a/tracker/software/drivers/wrapper/padc.h
+++ b/tracker/software/drivers/wrapper/padc.h
@@ -8,6 +8,7 @@
 
 void initADC(void);
 void deinitADC(void);
+uint16_t getBatteryVoltageMV_STM32(void);
 uint16_t getBatteryVoltageMV(void);
 uint16_t getSolarVoltageMV(void);
 uint16_t getUSBVoltageMV(void);
diff --git a/tracker/software/modules/position.c b/tracker/software/modules/position.c
index 7ea210a..4ac1365 100644
--- a/tracker/software/modules/position.c
+++ b/tracker/software/modules/position.c
@@ -93,8 +93,8 @@ void replace_placeholders(char* fskmsg, uint16_t size, trackPoint_t *tp) {
 	str_replace(fskmsg, size, "<VSOL>", buf);
 	chsnprintf(buf, sizeof(buf), "%d.%03d", tp->adc_pbat/1000, (tp->adc_pbat >= 0 ? 1 : -1) * (tp->adc_pbat%1000));
 	str_replace(fskmsg, size, "<PBAT>", buf);
-	chsnprintf(buf, sizeof(buf), "%d.%03d", tp->adc_isol/1000, (tp->adc_isol >= 0 ? 1 : -1) * (tp->adc_isol%1000));
-	str_replace(fskmsg, size, "<ISOL>", buf);
+	chsnprintf(buf, sizeof(buf), "%d.%03d", tp->adc_rbat/1000, (tp->adc_rbat >= 0 ? 1 : -1) * (tp->adc_rbat%1000));
+	str_replace(fskmsg, size, "<RBAT>", buf);
 	chsnprintf(buf, sizeof(buf), "%d", tp->air_press/10);
 	str_replace(fskmsg, size, "<PRESS>", buf);
 	chsnprintf(buf, sizeof(buf), "%d.%d", tp->air_temp/100, (tp->air_temp%100)/10);
diff --git a/tracker/software/modules/tracking.c b/tracker/software/modules/tracking.c
index 96b76ee..db1c85c 100644
--- a/tracker/software/modules/tracking.c
+++ b/tracker/software/modules/tracking.c
@@ -179,7 +179,7 @@ THD_FUNCTION(trackingThread, arg) {
 		lastTrackPoint->gps_alt = lastLogPoint.gps_alt;
 	}
 
-	lastTrackPoint->gps_lock = 0; // But tell the user that there is no current lock nor any GPS sats locked
+	lastTrackPoint->gps_lock = GPS_LOSS; // But tell the user that there is no current lock nor any GPS sats locked
 	lastTrackPoint->gps_sats = 0;
 	lastTrackPoint->gps_ttff = 0;
 
@@ -202,7 +202,6 @@ THD_FUNCTION(trackingThread, arg) {
 	lastTrackPoint->adc_vsol = getSolarVoltageMV();
 	lastTrackPoint->adc_vbat = getBatteryVoltageMV();
 	lastTrackPoint->adc_vusb = getUSBVoltageMV();
-	lastTrackPoint->adc_isol = pac1720_getIsol();
 	lastTrackPoint->adc_pbat = pac1720_getPbat();
 
 	bme280_t bme280;
@@ -278,13 +277,17 @@ THD_FUNCTION(trackingThread, arg) {
 			tp->gps_lon = gpsFix.lon;
 			tp->gps_alt = gpsFix.alt;
 
-			tp->gps_lock = isGPSLocked(&gpsFix);
+			tp->gps_lock = GPS_LOCKED;
 			tp->gps_sats = gpsFix.num_svs;
 
 		} else { // GPS lost (keep GPS switched on)
 
 			// Debug
-			TRACE_WARN("TRAC > GPS sampling finished GPS LOSS");
+			if(batt < GPS_OFF_VBAT) {
+				TRACE_WARN("TRAC > GPS sampling finished GPS LOW BATT");
+			} else {
+				TRACE_WARN("TRAC > GPS sampling finished GPS LOSS");
+			}
 
 			// Take time from internal RTC
 			getTime(&rtc);
@@ -300,8 +303,8 @@ THD_FUNCTION(trackingThread, arg) {
 			tp->gps_lon = ltp->gps_lon;
 			tp->gps_alt = ltp->gps_alt;
 
-			// Mark gpsloss
-			tp->gps_lock = false;
+			// Mark GPS loss (or low batt)
+			tp->gps_lock = batt < GPS_OFF_VBAT ? GPS_LOWBATT : GPS_LOSS;
 			tp->gps_sats = 0;
 
 		}
@@ -313,8 +316,8 @@ THD_FUNCTION(trackingThread, arg) {
 		tp->adc_vsol = getSolarVoltageMV();
 		tp->adc_vbat = getBatteryVoltageMV();
 		tp->adc_vusb = getUSBVoltageMV();
-		tp->adc_isol = pac1720_getIsol();
 		tp->adc_pbat = pac1720_getAvgPbat();
+		tp->adc_rbat = pac1720_getAvgRbat();
 
 		bme280_t bme280;
 
@@ -336,13 +339,13 @@ THD_FUNCTION(trackingThread, arg) {
 					"%s Time %04d-%02d-%02d %02d:%02d:%02d\r\n"
 					"%s Pos  %d.%05d %d.%05d Alt %dm\r\n"
 					"%s Sats %d  TTFF %dsec\r\n"
-					"%s ADC Vbat=%d.%03dV Vsol=%d.%03dV VUSB=%d.%03dV Pbat=%dmW Isol=%dmA\r\n"
+					"%s ADC Vbat=%d.%03dV Vsol=%d.%03dV VUSB=%d.%03dV Pbat=%dmW Rbat=%dmOhm\r\n"
 					"%s AIR p=%6d.%01dPa T=%2d.%02ddegC phi=%2d.%01d%%",
 					tp->id,
 					TRACE_TAB, tp->time.year, tp->time.month, tp->time.day, tp->time.hour, tp->time.minute, tp->time.day,
 					TRACE_TAB, tp->gps_lat/10000000, (tp->gps_lat > 0 ? 1:-1)*(tp->gps_lat/100)%100000, tp->gps_lon/10000000, (tp->gps_lon > 0 ? 1:-1)*(tp->gps_lon/100)%100000, tp->gps_alt,
 					TRACE_TAB, tp->gps_sats, tp->gps_ttff,
-					TRACE_TAB, tp->adc_vbat/1000, (tp->adc_vbat%1000), tp->adc_vsol/1000, (tp->adc_vsol%1000), tp->adc_vusb/1000, (tp->adc_vusb%1000), tp->adc_pbat, tp->adc_isol,
+					TRACE_TAB, tp->adc_vbat/1000, (tp->adc_vbat%1000), tp->adc_vsol/1000, (tp->adc_vsol%1000), tp->adc_vusb/1000, (tp->adc_vusb%1000), tp->adc_pbat, tp->adc_rbat,
 					TRACE_TAB, tp->air_press/10, tp->air_press%10, tp->air_temp/100, tp->air_temp%100, tp->air_hum/10, tp->air_hum%10
 		);
 
diff --git a/tracker/software/modules/tracking.h b/tracker/software/modules/tracking.h
index ea84155..c9b6c42 100644
--- a/tracker/software/modules/tracking.h
+++ b/tracker/software/modules/tracking.h
@@ -5,12 +5,16 @@
 #include "hal.h"
 #include "ptime.h"
 
+#define GPS_LOCKED	0	/* GPS is locked and could aquire a fix */
+#define GPS_LOSS	1	/* GPS was switched on all time but it couln't aquire a fix */
+#define GPS_LOWBATT	2	/* GPS was switched on but had to be switched off prematurely while the battery is almost empty (or is too cold) */
+
 typedef struct {
 	uint32_t id;			// Serial ID
 	ptime_t time;			// GPS time
 
 	// GPS
-	bool gps_lock;			// True = on last try GPS has been locked
+	uint8_t gps_lock;		// 0: locked, 1: GPS loss, 2: low power (switched off)
 	int32_t gps_lat;		// Latitude in °*10^7
 	int32_t gps_lon;		// Longitude in °*10^7
 	int32_t gps_alt;		// Altitude in meter
@@ -22,7 +26,7 @@ typedef struct {
 	uint16_t adc_vbat;		// Current battery voltage in mV
 	uint16_t adc_vusb;		// Current USB voltage in mV
 	int16_t adc_pbat;		// Average battery current (since last track point)
-	int16_t adc_isol;		// Current solar shot current
+	int16_t adc_rbat;		// Battery impedance
 
 	// BME280 (on board)
 	uint32_t air_press;		// Airpressure in Pa*10 (in 0.1Pa)
diff --git a/tracker/software/protocols/aprs/aprs.c b/tracker/software/protocols/aprs/aprs.c
index 7cae199..09923eb 100644
--- a/tracker/software/protocols/aprs/aprs.c
+++ b/tracker/software/protocols/aprs/aprs.c
@@ -77,7 +77,7 @@ uint32_t aprs_encode_position(uint8_t* message, mod_t mod, const aprs_conf_t *co
 	uint32_t a1  = a / 91;
 	uint32_t a1r = a % 91;
 
-	uint8_t gpsFix = trackPoint->gps_lock ? GSP_FIX_CURRENT : GSP_FIX_OLD;
+	uint8_t gpsFix = trackPoint->gps_lock ? GSP_FIX_OLD : GSP_FIX_CURRENT;
 	uint8_t src = NMEA_SRC_GGA;
 	uint8_t origin = ORIGIN_PICO;
 
@@ -103,7 +103,7 @@ uint32_t aprs_encode_position(uint8_t* message, mod_t mod, const aprs_conf_t *co
 	chsnprintf(temp, sizeof(temp), "%d", trackPoint->gps_sats);
 	ax25_send_string(&packet, temp);
 
-	if(trackPoint->gps_lock)
+	if(trackPoint->gps_lock == GPS_LOCKED) // GPS is locked
 	{
 		// TTFF (Time to first fix)
 		ax25_send_string(&packet, " TTFF ");
@@ -112,12 +112,18 @@ uint32_t aprs_encode_position(uint8_t* message, mod_t mod, const aprs_conf_t *co
 		ax25_send_string(&packet, "sec");
 	}
 
-	// GPS Loss counter
-	if(!trackPoint->gps_lock)
-	{
+	if(trackPoint->gps_lock == GPS_LOSS) { // No GPS lock
+
 		ax25_send_string(&packet, " GPS LOSS ");
 		chsnprintf(temp, sizeof(temp), "%d", ++loss_of_gps_counter);
 		ax25_send_string(&packet, temp);
+
+	} else if(trackPoint->gps_lock == GPS_LOWBATT) { // GPS switched off prematurely
+
+		ax25_send_string(&packet, " GPS LOWBATT ");
+		chsnprintf(temp, sizeof(temp), "%d", ++loss_of_gps_counter);
+		ax25_send_string(&packet, temp);
+
 	} else {
 		loss_of_gps_counter = 0;
 	}
@@ -140,7 +146,7 @@ uint32_t aprs_encode_position(uint8_t* message, mod_t mod, const aprs_conf_t *co
 			case TEL_VBAT:	t = trackPoint->adc_vbat;			break;
 			case TEL_VSOL:	t = trackPoint->adc_vsol;			break;
 			case TEL_PBAT:	t = trackPoint->adc_pbat+4096;		break;
-			case TEL_ISOL:	t = trackPoint->adc_isol;			break;
+			case TEL_RBAT:	t = trackPoint->adc_rbat;			break;
 			case TEL_HUM:	t = trackPoint->air_hum;			break;
 			case TEL_PRESS:	t = trackPoint->air_press/125 - 40;	break;
 			case TEL_TEMP:	t = trackPoint->air_temp/10 + 1000;	break;
@@ -259,7 +265,7 @@ uint32_t aprs_encode_telemetry_configuration(uint8_t* message, mod_t mod, const
 					case TEL_VBAT:		ax25_send_string(&packet, "Vbat");			break;
 					case TEL_VSOL:		ax25_send_string(&packet, "Vsol");			break;
 					case TEL_PBAT:		ax25_send_string(&packet, "Pbat");			break;
-					case TEL_ISOL:		ax25_send_string(&packet, "Isol");			break;
+					case TEL_RBAT:		ax25_send_string(&packet, "Rbat");			break;
 					case TEL_HUM:		ax25_send_string(&packet, "Humidity");		break;
 					case TEL_PRESS:		ax25_send_string(&packet, "Airpressure");	break;
 					case TEL_TEMP:		ax25_send_string(&packet, "Temperature");	break;
@@ -292,8 +298,8 @@ uint32_t aprs_encode_telemetry_configuration(uint8_t* message, mod_t mod, const
 						ax25_send_string(&packet, "W");
 						break;
 
-					case TEL_ISOL:
-						ax25_send_string(&packet, "A");
+					case TEL_RBAT:
+						ax25_send_string(&packet, "Ohm");
 						break;
 
 					case TEL_HUM:
@@ -325,10 +331,9 @@ uint32_t aprs_encode_telemetry_configuration(uint8_t* message, mod_t mod, const
 						ax25_send_string(&packet, "0,1,0");
 						break;
 
-
-					case TEL_ISOL:
 					case TEL_VBAT:
 					case TEL_VSOL:
+					case TEL_RBAT:
 						ax25_send_string(&packet, "0,.001,0");
 						break;
 
diff --git a/tracker/software/sleep.c b/tracker/software/sleep.c
index 87eb410..2db9897 100644
--- a/tracker/software/sleep.c
+++ b/tracker/software/sleep.c
@@ -17,14 +17,14 @@ bool p_sleep(const sleep_conf_t *config)
 		case SLEEP_WHEN_VBAT_BELOW_THRES:
 			return getBatteryVoltageMV() < config->vbat_thres;
 
-		case SLEEP_WHEN_ISOL_BELOW_THRES:
-			return pac1720_getIsol() < config->isol_thres;
+		case SLEEP_WHEN_RBAT_BELOW_THRES:
+			return 0 < config->rbat_thres; // FIXME
 
 		case SLEEP_WHEN_VBAT_ABOVE_THRES:
 			return getBatteryVoltageMV() > config->vbat_thres;
 
-		case SLEEP_WHEN_ISOL_ABOVE_THRES:
-			return pac1720_getIsol() > config->isol_thres;
+		case SLEEP_WHEN_RBAT_ABOVE_THRES:
+			return 0 > config->rbat_thres; // FIXME
 
 		case SLEEP_WHEN_DISCHARGING:
 		case SLEEP_WHEN_CHARGING:
diff --git a/tracker/software/types.h b/tracker/software/types.h
index 521e35b..9331c5f 100644
--- a/tracker/software/types.h
+++ b/tracker/software/types.h
@@ -31,7 +31,7 @@ typedef enum {
 	TEL_VBAT,
 	TEL_VSOL,
 	TEL_PBAT,
-	TEL_ISOL,
+	TEL_RBAT,
 	TEL_PRESS,
 	TEL_TEMP,
 	TEL_HUM
@@ -52,9 +52,9 @@ typedef struct {
 typedef enum {
 	SLEEP_DISABLED,
 	SLEEP_WHEN_VBAT_BELOW_THRES,
-	SLEEP_WHEN_ISOL_BELOW_THRES,
+	SLEEP_WHEN_RBAT_BELOW_THRES,
 	SLEEP_WHEN_VBAT_ABOVE_THRES,
-	SLEEP_WHEN_ISOL_ABOVE_THRES,
+	SLEEP_WHEN_RBAT_ABOVE_THRES,
 	SLEEP_WHEN_DISCHARGING,
 	SLEEP_WHEN_CHARGING
 } sleep_type_t;
@@ -62,7 +62,7 @@ typedef enum {
 typedef struct {
 	sleep_type_t type;
 	uint16_t vbat_thres;
-	uint16_t isol_thres;
+	uint16_t rbat_thres;
 } sleep_conf_t;
 
 typedef struct {