diff --git a/lib/obp60task/OBP60Extensions.cpp b/lib/obp60task/OBP60Extensions.cpp
index c589feb..83e9ed6 100644
--- a/lib/obp60task/OBP60Extensions.cpp
+++ b/lib/obp60task/OBP60Extensions.cpp
@@ -421,32 +421,49 @@ void displayHeader(CommonData &commonData, GwApi::BoatValue *date, GwApi::BoatVa
         heartbeat = !heartbeat;
 
         // Date and time
+        String fmttype = commonData.config->getString(commonData.config->dateFormat);
+        String timesource = commonData.config->getString(commonData.config->timeSource);
+        double tz = commonData.config->getString(commonData.config->timeZone).toDouble();
         getdisplay().setTextColor(commonData.fgcolor);
         getdisplay().setFont(&Ubuntu_Bold8pt7b);
         getdisplay().setCursor(230, 15);
-        // Show date and time if date present
-        if(date->valid == true){
-            String acttime = formatValue(time, commonData).svalue;
-            acttime = acttime.substring(0, 5);
-            String actdate = formatValue(date, commonData).svalue;
-            getdisplay().print(acttime);
-            getdisplay().print(" ");
-            getdisplay().print(actdate);
-            getdisplay().print(" ");
-            if(commonData.config->getInt(commonData.config->timeZone) == 0){
-                getdisplay().print("UTC");
-            }
-            else{
-                getdisplay().print("LOT");
+        if (timesource == "RTC" or timesource == "iRTC") {
+            // TODO take DST into account
+            if (commonData.data.rtcValid) {
+                time_t tv = mktime(&commonData.data.rtcTime) + (int)(tz * 3600);
+                struct tm *local_tm = localtime(&tv);
+                getdisplay().print(formatTime('m', local_tm->tm_hour, local_tm->tm_min, 0));
+                getdisplay().print(" ");
+                getdisplay().print(formatDate(fmttype, local_tm->tm_year + 1900, local_tm->tm_mon + 1, local_tm->tm_mday));
+                getdisplay().print(" ");
+                getdisplay().print(tz == 0 ? "UTC" : "LOT");
+            } else {
+                drawTextRalign(396, 15, "RTC invalid");
             }
         }
-        else{
-            if(commonData.config->getBool(commonData.config->useSimuData) == true){
-                getdisplay().print("12:00 01.01.2024 LOT");
+        else if (timesource == "GPS") {
+            // Show date and time if date present
+            if(date->valid == true){
+                String acttime = formatValue(time, commonData).svalue;
+                acttime = acttime.substring(0, 5);
+                String actdate = formatValue(date, commonData).svalue;
+                getdisplay().print(acttime);
+                getdisplay().print(" ");
+                getdisplay().print(actdate);
+                getdisplay().print(" ");
+                getdisplay().print(tz == 0 ? "UTC" : "LOT");
             }
             else{
-                getdisplay().print("No GPS data");
+                if(commonData.config->getBool(commonData.config->useSimuData) == true){
+                    getdisplay().print("12:00 01.01.2024 LOT");
+                }
+                else{
+                    drawTextRalign(396, 15, "No GPS data");
+                }
             }
+        } // timesource == "GPS"
+        else {
+            getdisplay().print("No time source");
         }
     }
 }
@@ -528,8 +545,7 @@ void displayFooter(CommonData &commonData) {
 }
 
 // Sunset und sunrise calculation
-SunData calcSunsetSunrise(GwApi *api, double time, double date, double latitude, double longitude, double timezone){
-    GwLog *logger=api->getLogger();
+SunData calcSunsetSunrise(double time, double date, double latitude, double longitude, float timezone){
     SunData returnset;
     SunRise sr;
     int secPerHour = 3600;
@@ -543,8 +559,7 @@ SunData calcSunsetSunrise(GwApi *api, double time, double date, double latitude,
     if (!isnan(time) && !isnan(date) && !isnan(latitude) && !isnan(longitude) && !isnan(timezone)) {
         
         // Calculate local epoch
-        t = (date * secPerYear) + time;    
-        // api->getLogger()->logDebug(GwLog::DEBUG,"... calcSun: Lat %f, Lon  %f, at: %d ", latitude, longitude, t);
+        t = (date * secPerYear) + time;
         sr.calculate(latitude, longitude, t);       // LAT, LON, EPOCH
         // Sunrise
         if (sr.hasRise) {
@@ -567,6 +582,37 @@ SunData calcSunsetSunrise(GwApi *api, double time, double date, double latitude,
     return returnset;
 }
 
+SunData calcSunsetSunriseRTC(struct tm *rtctime, double latitude, double longitude, float timezone) {
+    SunData returnset;
+    SunRise sr;
+    const int secPerHour = 3600;
+    const int secPerYear = 86400;
+    sr.hasRise = false;
+    sr.hasSet = false;
+    time_t t =  mktime(rtctime) + timezone * 3600;;
+    time_t sunR = 0;
+    time_t sunS = 0;
+
+    sr.calculate(latitude, longitude, t);       // LAT, LON, EPOCH
+    // Sunrise
+    if (sr.hasRise) {
+        sunR = (sr.riseTime + int(timezone * secPerHour) + 30) % secPerYear; // add 30 seconds: round to minutes
+        returnset.sunriseHour = int (sunR / secPerHour);
+        returnset.sunriseMinute = int((sunR - returnset.sunriseHour * secPerHour) / 60);
+    }
+    // Sunset
+    if (sr.hasSet) {
+        sunS = (sr.setTime + int(timezone * secPerHour) + 30) % secPerYear; // add 30 seconds: round to minutes
+        returnset.sunsetHour = int (sunS / secPerHour);
+        returnset.sunsetMinute = int((sunS - returnset.sunsetHour * secPerHour) / 60);
+    }
+    // Sun control (return value by sun on sky = false, sun down = true)
+    if ((t >= sr.riseTime) && (t <= sr.setTime))
+         returnset.sunDown = false;
+    else returnset.sunDown = true;
+    return returnset;
+}
+
 // Battery graphic with fill level
 void batteryGraphic(uint x, uint y, float percent, int pcolor, int bcolor){
     // Show battery
diff --git a/lib/obp60task/OBP60Extensions.h b/lib/obp60task/OBP60Extensions.h
index 4118623..b878d00 100644
--- a/lib/obp60task/OBP60Extensions.h
+++ b/lib/obp60task/OBP60Extensions.h
@@ -97,7 +97,8 @@ void displayTrendLow(int16_t x, int16_t y, uint16_t size, uint16_t color);
 void displayHeader(CommonData &commonData, GwApi::BoatValue *date, GwApi::BoatValue *time, GwApi::BoatValue *hdop); // Draw display header
 void displayFooter(CommonData &commonData);
 
-SunData calcSunsetSunrise(GwApi *api, double time, double date, double latitude, double longitude, double timezone); // Calulate sunset and sunrise
+SunData calcSunsetSunrise(double time, double date, double latitude, double longitude, float timezone); // Calulate sunset and sunrise
+SunData calcSunsetSunriseRTC(struct tm *rtctime, double latitude, double longitude, float timezone);
 
 void batteryGraphic(uint x, uint y, float percent, int pcolor, int bcolor); // Battery graphic with fill level
 void solarGraphic(uint x, uint y, int pcolor, int bcolor);                  // Solar graphic
diff --git a/lib/obp60task/OBP60Formater.cpp b/lib/obp60task/OBP60Formater.cpp
index 54e9fb9..5b9745d 100644
--- a/lib/obp60task/OBP60Formater.cpp
+++ b/lib/obp60task/OBP60Formater.cpp
@@ -8,6 +8,35 @@
 // simulation data
 // hold values by missing data
 
+String formatDate(String fmttype, uint16_t year, uint8_t month, uint8_t day) {
+    char buffer[12];
+    if (fmttype == "GB") {
+        snprintf(buffer, 12, "%02d/%02d/%04d", day , month, year);
+    }
+    else if (fmttype == "US") {
+        snprintf(buffer, 12, "%02d/%02d/%04d", month, day, year);
+    }
+    else if (fmttype == "ISO") {
+        snprintf(buffer, 12, "%04d-%02d-%02d", year, month, day);
+    }
+    else {
+        snprintf(buffer, 12, "%02d.%02d.%04d", day, month, year);
+    }
+    return String(buffer);
+}
+
+String formatTime(char fmttype, uint8_t hour, uint8_t minute, uint8_t second) {
+    // fmttype: s: with seconds, m: only minutes
+    char buffer[10];
+    if (fmttype == 'm') {
+        snprintf(buffer, 10, "%02d:%02d", hour , minute);
+    }
+    else {
+        snprintf(buffer, 10, "%02d:%02d:%02d", hour, minute, second);
+    }
+    return String(buffer);
+}
+
 FormatedData formatValue(GwApi::BoatValue *value, CommonData &commondata){
     GwLog *logger = commondata.logger;
     FormatedData result;
diff --git a/lib/obp60task/OBPSensorTask.cpp b/lib/obp60task/OBPSensorTask.cpp
index a6d112c..500389e 100644
--- a/lib/obp60task/OBPSensorTask.cpp
+++ b/lib/obp60task/OBPSensorTask.cpp
@@ -17,9 +17,11 @@
 #include "ObpNmea0183.h"                // Check NMEA0183 sentence for uncorrect content
 #include "OBP60Extensions.h"            // Lib for hardware extensions
 #include "movingAvg.h"                  // Lib for moving average building
+#include "time.h"                       // For getting NTP time
+#include <ESP32Time.h>                  // Internal ESP32 RTC clock
 
 // Timer for hardware functions
-Ticker Timer1(blinkingFlashLED, 500);   // Satrt Timer1 for flash LED all 500ms
+Ticker Timer1(blinkingFlashLED, 500);   // Start Timer1 for flash LED all 500ms
 
 // Initialization for all sensors (RS232, I2C, 1Wire, IOs)
 //####################################################################################
@@ -150,6 +152,7 @@ void sensorTask(void *param){
                 // ds1388.adjust(DateTime(__DATE__, __TIME__));  // Set date and time from PC file time
             }
             RTC_ready = true;
+            sensors.rtcValid = true;
         }
     }
 
@@ -366,6 +369,28 @@ void sensorTask(void *param){
     GwApi::BoatValue *hdop=new GwApi::BoatValue(GwBoatData::_HDOP);
     GwApi::BoatValue *valueList[]={gpsdays, gpsseconds, hdop};
 
+    // Internal RTC with NTP init
+    ESP32Time rtc(0);
+    if (api->getConfig()->getString(api->getConfig()->timeSource) == "iRTC") {
+        GwApi::Status status;
+        api->getStatus(status);
+        if (status.wifiClientConnected) {
+            const char *ntpServer = api->getConfig()->getCString(api->getConfig()->timeServer);
+            api->getLogger()->logDebug(GwLog::LOG,"Fetching date and time from NTP server '%s'.", ntpServer);
+            configTime(0, 0, ntpServer); // get time in UTC
+            struct tm timeinfo;
+            if (getLocalTime(&timeinfo)) {
+                api->getLogger()->logDebug(GwLog::LOG,"NTP time: %04d-%02d-%02d %02d:%02d:%02d UTC", timeinfo.tm_year+1900, timeinfo.tm_mon+1, timeinfo.tm_mday, timeinfo.tm_hour, timeinfo.tm_min, timeinfo.tm_sec);
+                rtc.setTimeStruct(timeinfo);
+                sensors.rtcValid = true;
+            } else {
+                api->getLogger()->logDebug(GwLog::LOG,"NTP time fetch failed!");
+            }
+        } else {
+            api->getLogger()->logDebug(GwLog::LOG,"Wifi client not connected, NTP not available.");
+        }
+    }
+
     // Sensor task loop runs with 100ms
     //####################################################################################
 
@@ -428,39 +453,45 @@ void sensorTask(void *param){
             loopCounter++;
         }
 
-        // If GPS not ready or installed then send RTC time on bus all 500ms
-        if(millis() > starttime12 + 500){
+        // Get current RTC date and time all 500ms
+        if (millis() > starttime12 + 500) {
             starttime12 = millis();
-            if((rtcOn == "DS1388" && RTC_ready == true && GPS_ready == false) || (rtcOn == "DS1388" && RTC_ready == true && GPS_ready == true && hdop->valid == false)){
-                // Convert RTC time to Unix system time
-                // https://de.wikipedia.org/wiki/Unixzeit
-                const short daysOfYear[12] = {0,31,59,90,120,151,181,212,243,273,304,334};
-                long unixtime = ds1388.now().get();
-                uint16_t year = ds1388.now().year();
-                uint8_t month = ds1388.now().month();
-                uint8_t hour = ds1388.now().hour();
-                uint8_t minute = ds1388.now().minute();
-                uint8_t second = ds1388.now().second();
-                uint8_t day = ds1388.now().day();
-                uint16_t switchYear = ((year-1)-1968)/4 - ((year-1)-1900)/100 + ((year-1)-1600)/400;
-                long daysAt1970 = (year-1970)*365 + switchYear + daysOfYear[month-1] + day-1;
-                // If switch year then add one day
-                if ( (month>2) && (year%4==0 && (year%100!=0 || year%400==0)) ){
-                    daysAt1970 += 1;
-                }
-                double sysTime = (hour * 3600) + (minute * 60) + second;
-                if(!isnan(daysAt1970) && !isnan(sysTime)){
-                    sensors.rtcYear = year; // Save values in SensorData
-                    sensors.rtcMonth = month;
-                    sensors.rtcDay = day;
-                    sensors.rtcHour = hour;
-                    sensors.rtcMinute = minute;
-                    sensors.rtcSecond = second;
-                    // api->getLogger()->logDebug(GwLog::LOG,"RTC time: %04d/%02d/%02d %02d:%02d:%02d",year, month, day, hour, minute, second);
-                    // api->getLogger()->logDebug(GwLog::LOG,"Send PGN126992: %10d %10d",daysAt1970, (uint16_t)sysTime);
-                    SetN2kPGN126992(N2kMsg,0,daysAt1970,sysTime,N2ktimes_LocalCrystalClock);
-                    api->sendN2kMessage(N2kMsg);
+            if (rtcOn == "DS1388" && RTC_ready) {
+                DateTime dt = ds1388.now();
+                sensors.rtcTime.tm_year  = dt.year() - 1900; // Save values in SensorData
+                sensors.rtcTime.tm_mon = dt.month() - 1;
+                sensors.rtcTime.tm_mday = dt.day();
+                sensors.rtcTime.tm_hour = dt.hour();
+                sensors.rtcTime.tm_min = dt.minute();
+                sensors.rtcTime.tm_sec = dt.second();
+                sensors.rtcTime.tm_isdst = 0; // Not considering daylight saving time
+
+                // If GPS not ready or installed then send RTC time on bus
+                // TODO If there are other time sources on the bus there should
+                //      be a logic not to send or to send with lower frequency
+                //      or something totally different
+                if ((GPS_ready == false) || (GPS_ready == true && hdop->valid == false)) {
+                    // TODO implement daysAt1970 and sysTime as methods of DateTime
+                    const short daysOfYear[12] = {0,31,59,90,120,151,181,212,243,273,304,334};
+                    uint16_t switchYear = ((dt.year()-1)-1968)/4 - ((dt.year()-1)-1900)/100 + ((dt.year()-1)-1600)/400;
+                    long daysAt1970 = (dt.year()-1970)*365 + switchYear + daysOfYear[dt.month()-1] + dt.day()-1;
+                    // If switch year then add one day
+                    if ((dt.month() > 2) && (dt.year() % 4 == 0  && (dt.year() % 100 != 0 || dt.year() % 400 == 0))) {
+                        daysAt1970 += 1;
+                    }
+                    // N2K sysTime is double in n2klib
+                    double sysTime = (dt.hour() * 3600) + (dt.minute() * 60) + dt.second();
+                    // WHY? isnan should always fail here
+                    //if(!isnan(daysAt1970) && !isnan(sysTime)){
+                        //api->getLogger()->logDebug(GwLog::LOG,"RTC time: %04d/%02d/%02d %02d:%02d:%02d",sensors.rtcTime.tm_year+1900,sensors.rtcTime.tm_mon, sensors.rtcTime.tm_mday, sensors.rtcTime.tm_hour, sensors.rtcTime.tm_min, sensors.rtcTime.tm_sec);
+                        //api->getLogger()->logDebug(GwLog::LOG,"Send PGN126992: %10d %10d",daysAt1970, (uint16_t)sysTime);
+                        SetN2kPGN126992(N2kMsg,0,daysAt1970,sysTime,N2ktimes_LocalCrystalClock);
+                        api->sendN2kMessage(N2kMsg);
+                    // }
                 }
+            } else if (sensors.rtcValid) {
+                // use internal rtc feature
+                sensors.rtcTime = rtc.getTimeStruct();
             }
         }
 
diff --git a/lib/obp60task/PageClock.cpp b/lib/obp60task/PageClock.cpp
index 906956a..b3cea6b 100644
--- a/lib/obp60task/PageClock.cpp
+++ b/lib/obp60task/PageClock.cpp
@@ -3,24 +3,83 @@
 #include "Pagedata.h"
 #include "OBP60Extensions.h"
 
+/*
+ * TODO mode: race timer: keys
+ *   - prepare: set countdown to 5min
+ *     reset: abort current countdown and start over with 5min preparation
+ *   - 5min: key press
+ *   - 4min: key press to sync
+ *   - 1min: buzzer signal
+ *   - start: buzzer signal for start
+ *
+ */
+
 class PageClock : public Page
 {
-    bool simulation = false;
-    int simtime;
+bool simulation = false;
+int simtime;
+bool keylock = false;
+char source = 'R';  // time source (R)TC | (G)PS | (N)TP
+char mode = 'A';    // display mode (A)nalog | (D)igital | race (T)imer
+char tz = 'L';      // time zone (L)ocal | (U)TC
+double timezone = 0; // there are timezones with non int offsets, e.g. 5.5 or 5.75
+double homelat;
+double homelon;
+bool homevalid = false; // homelat and homelon are valid
 
     public:
     PageClock(CommonData &common){
         commonData = &common;
         common.logger->logDebug(GwLog::LOG,"Instantiate PageClock");
         simulation = common.config->getBool(common.config->useSimuData);
+        timezone = common.config->getString(common.config->timeZone).toDouble();
+        homelat = common.config->getString(common.config->homeLAT).toDouble();
+        homelon = common.config->getString(common.config->homeLON).toDouble();
+        homevalid = homelat >= -180.0 and homelat <= 180 and homelon >= -90.0 and homelon <= 90.0;
         simtime = 38160; // time value 11:36
     }
 
+    virtual void setupKeys(){
+        Page::setupKeys();
+        commonData->keydata[0].label = "SRC";
+        commonData->keydata[1].label = "MODE";
+        commonData->keydata[4].label = "TZ";
+    }
+
     // Key functions
     virtual int handleKey(int key){
-         // Code for keylock
-        if(key == 11){
-            commonData->keylock = !commonData->keylock;
+        // Time source
+        if (key == 1) {
+            if (source == 'G') {
+                source = 'R';
+            } else {
+                source = 'G';
+            }
+            return 0;
+        }
+        if (key == 2) {
+            if (mode == 'A') {
+                mode = 'D';
+            } else if (mode == 'D') {
+                mode = 'T';
+            } else {
+                mode = 'A';
+            }
+            return 0;
+        }
+        // Time zone: Local / UTC
+        if (key == 5) {
+            if (tz == 'L') {
+                tz = 'U';
+            } else {
+                tz = 'L';
+            }
+            return 0;
+        }
+
+        // Keylock function
+        if(key == 11){              // Code for keylock
+            keylock = !keylock;     // Toggle keylock
             return 0;               // Commit the key
         }
         return key;
@@ -47,11 +106,10 @@ class PageClock : public Page
 
         // Get config data
         String lengthformat = config->getString(config->lengthFormat);
+        String dateformat = config->getString(config->dateFormat);
         bool holdvalues = config->getBool(config->holdvalues);
         String flashLED = config->getString(config->flashLED);
         String backlightMode = config->getString(config->backlight);
-        String stimezone = config->getString(config->timeZone);
-        double timezone = stimezone.toDouble();
 
         // Get boat values for GPS time
         GwApi::BoatValue *bvalue1 = pageData.values[0]; // First element in list (only one value by PageOneValue)
@@ -67,7 +125,7 @@ class PageClock : public Page
         String svalue1 = formatValue(bvalue1, *commonData).svalue;    // Formatted value as string including unit conversion and switching decimal places
         String unit1 = formatValue(bvalue1, *commonData).unit;        // Unit of value
         if(valid1 == true){
-            svalue1old = svalue1;   	                // Save old value
+            svalue1old = svalue1;                       // Save old value
             unit1old = unit1;                           // Save old unit
         }
 
@@ -80,7 +138,7 @@ class PageClock : public Page
         String svalue2 = formatValue(bvalue2, *commonData).svalue;    // Formatted value as string including unit conversion and switching decimal places
         String unit2 = formatValue(bvalue2, *commonData).unit;        // Unit of value
         if(valid2 == true){
-            svalue2old = svalue2;   	                // Save old value
+            svalue2old = svalue2;                       // Save old value
             unit2old = unit2;                           // Save old unit
         }
 
@@ -93,14 +151,14 @@ class PageClock : public Page
         String svalue3 = formatValue(bvalue3, *commonData).svalue;    // Formatted value as string including unit conversion and switching decimal places
         String unit3 = formatValue(bvalue3, *commonData).unit;        // Unit of value
         if(valid3 == true){
-            svalue3old = svalue3;   	                // Save old value
+            svalue3old = svalue3;                       // Save old value
             unit3old = unit3;                           // Save old unit
         }
 
         // Optical warning by limit violation (unused)
         if(String(flashLED) == "Limit Violation"){
             setBlinkingLED(false);
-            setFlashLED(false); 
+            setFlashLED(false);
         }
 
         // Logging boat values
@@ -115,11 +173,30 @@ class PageClock : public Page
 
         getdisplay().setTextColor(commonData->fgcolor);
 
+        time_t tv = mktime(&commonData->data.rtcTime) + timezone * 3600;
+        struct tm *local_tm = localtime(&tv);
+
         // Show values GPS date
         getdisplay().setFont(&Ubuntu_Bold8pt7b);
         getdisplay().setCursor(10, 65);
-        if(holdvalues == false) getdisplay().print(svalue2); // Value
-        else getdisplay().print(svalue2old);
+        if (holdvalues == false) {
+            if (source == 'G') {
+                 // GPS value
+                 getdisplay().print(svalue2);
+            } else if (commonData->data.rtcValid) {
+                // RTC value
+                 if (tz == 'L') {
+                     getdisplay().print(formatDate(dateformat, local_tm->tm_year + 1900, local_tm->tm_mon + 1, local_tm->tm_mday));
+                 }
+                 else {
+                     getdisplay().print(formatDate(dateformat, commonData->data.rtcTime.tm_year + 1900, commonData->data.rtcTime.tm_mon + 1, commonData->data.rtcTime.tm_mday));
+                 }
+            } else {
+                getdisplay().print("---");
+            }
+        } else {
+            getdisplay().print(svalue2old);
+        }
         getdisplay().setFont(&Ubuntu_Bold12pt7b);
         getdisplay().setCursor(10, 95);
         getdisplay().print("Date");                          // Name
@@ -130,15 +207,31 @@ class PageClock : public Page
         // Show values GPS time
         getdisplay().setFont(&Ubuntu_Bold8pt7b);
         getdisplay().setCursor(10, 250);
-        if(holdvalues == false) getdisplay().print(svalue1); // Value
-        else getdisplay().print(svalue1old);
+        if (holdvalues == false) {
+            if (source == 'G') {
+                getdisplay().print(svalue1); // Value
+            }
+            else if (commonData->data.rtcValid) {
+                 if (tz == 'L') {
+                      getdisplay().print(formatTime('s', local_tm->tm_hour, local_tm->tm_min, local_tm->tm_sec));
+                 }
+                 else {
+                      getdisplay().print(formatTime('s', commonData->data.rtcTime.tm_hour, commonData->data.rtcTime.tm_min, commonData->data.rtcTime.tm_sec));
+                 }
+            } else {
+                getdisplay().print("---");
+            }
+        }
+        else {
+             getdisplay().print(svalue1old);
+        }
         getdisplay().setFont(&Ubuntu_Bold12pt7b);
         getdisplay().setCursor(10, 220);
         getdisplay().print("Time");                          // Name
 
         // Show values sunrise
         String sunrise = "---";
-        if(valid1 == true && valid2 == true && valid3 == true){
+        if ((valid1 and valid2 and valid3 == true) or (homevalid and commonData->data.rtcValid)) {
             sunrise = String(commonData->sundata.sunriseHour) + ":" + String(commonData->sundata.sunriseMinute + 100).substring(1);
             svalue5old = sunrise;
         } else if (simulation) {
@@ -158,7 +251,7 @@ class PageClock : public Page
 
         // Show values sunset
         String sunset = "---";
-        if(valid1 == true && valid2 == true && valid3 == true){
+        if ((valid1 and valid2 and valid3 == true) or (homevalid and commonData->data.rtcValid)) {
             sunset = String(commonData->sundata.sunsetHour) + ":" +  String(commonData->sundata.sunsetMinute + 100).substring(1);
             svalue6old = sunset;
         } else if (simulation) {
@@ -174,7 +267,7 @@ class PageClock : public Page
         getdisplay().print("SunS");                          // Name
 
 //*******************************************************************************************
-        
+
         // Draw clock
         int rInstrument = 110;     // Radius of clock
         float pi = 3.141592;
@@ -246,27 +339,52 @@ class PageClock : public Page
         getdisplay().setFont(&Ubuntu_Bold12pt7b);
         getdisplay().setCursor(175, 110);
         if(holdvalues == false){
-            getdisplay().print(unit2);                       // Unit
+            getdisplay().print(tz == 'L' ? "LOT" : "UTC");
         }
         else{
-            getdisplay().print(unit2old);                    // Unit
+            getdisplay().print(unit2old); // date unit
+        }
+
+        getdisplay().setFont(&Ubuntu_Bold8pt7b);
+        getdisplay().setCursor(185, 190);
+        if (source == 'G') {
+            getdisplay().print("GPS");
+        } else {
+            getdisplay().print("RTC");
         }
 
         // Clock values
         double hour = 0;
         double minute = 0;
-        value1 = value1 + int(timezone*3600);
-        if (value1 > 86400) {value1 = value1 - 86400;}
-        if (value1 < 0) {value1 = value1 + 86400;}
-        hour = (value1 / 3600.0);
-        if(hour > 12) hour = hour - 12.0;
-//        minute = (hour - int(hour)) * 3600.0 / 60.0;        // Analog minute pointer smooth moving
-        minute = int((hour - int(hour)) * 3600.0 / 60.0);   // Jumping minute pointer from minute to minute
+        if (source == 'R') {
+            if (tz == 'L') {
+                time_t tv = mktime(&commonData->data.rtcTime) + timezone * 3600;
+                struct tm *local_tm = localtime(&tv);
+                minute = local_tm->tm_min;
+                hour = local_tm->tm_hour;
+            } else {
+                minute = commonData->data.rtcTime.tm_min;
+                hour = commonData->data.rtcTime.tm_hour;
+            }
+            hour += minute / 60;
+        } else {
+            if (tz == 'L') {
+                value1 += timezone * 3600;
+            }
+            if (value1 > 86400) {value1 -= 86400;}
+            if (value1 < 0) {value1 += 86400;}
+            hour = (value1 / 3600.0);
+    //        minute = (hour - int(hour)) * 3600.0 / 60.0;        // Analog minute pointer smooth moving
+            minute = int((hour - int(hour)) * 3600.0 / 60.0);   // Jumping minute pointer from minute to minute
+        }
+        if (hour > 12) {
+            hour -= 12.0;
+        }
         LOG_DEBUG(GwLog::DEBUG,"... PageClock, value1: %f hour: %f minute:%f", value1, hour, minute);
-        
+
         // Draw hour pointer
         float startwidth = 8;       // Start width of pointer
-        if(valid1 == true || holdvalues == true || simulation == true){
+        if(valid1 == true || (source == 'R' && commonData->data.rtcValid) || holdvalues == true || simulation == true){
             float sinx=sin(hour * 30.0 * pi / 180);     // Hour
             float cosx=cos(hour * 30.0 * pi / 180);
             // Normal pointer
@@ -274,7 +392,7 @@ class PageClock : public Page
             float xx1 = -startwidth;
             float xx2 = startwidth;
             float yy1 = -startwidth;
-            float yy2 = -(rInstrument * 0.5); 
+            float yy2 = -(rInstrument * 0.5);
             getdisplay().fillTriangle(200+(int)(cosx*xx1-sinx*yy1),150+(int)(sinx*xx1+cosx*yy1),
                 200+(int)(cosx*xx2-sinx*yy1),150+(int)(sinx*xx2+cosx*yy1),
                 200+(int)(cosx*0-sinx*yy2),150+(int)(sinx*0+cosx*yy2),commonData->fgcolor);
@@ -292,7 +410,7 @@ class PageClock : public Page
 
         // Draw minute pointer
         startwidth = 8;       // Start width of pointer
-        if(valid1 == true || holdvalues == true || simulation == true){
+        if(valid1 == true || (source == 'R' && commonData->data.rtcValid) || holdvalues == true || simulation == true){
             float sinx=sin(minute * 6.0 * pi / 180);     // Minute
             float cosx=cos(minute * 6.0 * pi / 180);
             // Normal pointer
@@ -300,7 +418,7 @@ class PageClock : public Page
             float xx1 = -startwidth;
             float xx2 = startwidth;
             float yy1 = -startwidth;
-            float yy2 = -(rInstrument - 15); 
+            float yy2 = -(rInstrument - 15);
             getdisplay().fillTriangle(200+(int)(cosx*xx1-sinx*yy1),150+(int)(sinx*xx1+cosx*yy1),
                 200+(int)(cosx*xx2-sinx*yy1),150+(int)(sinx*xx2+cosx*yy1),
                 200+(int)(cosx*0-sinx*yy2),150+(int)(sinx*0+cosx*yy2),commonData->fgcolor);
diff --git a/lib/obp60task/Pagedata.h b/lib/obp60task/Pagedata.h
index b979b57..65bdc67 100644
--- a/lib/obp60task/Pagedata.h
+++ b/lib/obp60task/Pagedata.h
@@ -43,14 +43,10 @@ typedef struct{
   double airHumidity = 0;
   double airPressure = 0;
   double onewireTemp[8] = {0,0,0,0,0,0,0,0};
-  double rotationAngle = 0;       // Rotation angle in radiant
-  bool validRotAngle = false;     // Valid flag magnet present for rotation sensor
-  int rtcYear = 0;  // UTC time
-  int rtcMonth = 0;
-  int rtcDay = 0;
-  int rtcHour = 0;
-  int rtcMinute = 0;
-  int rtcSecond = 0;
+  double rotationAngle = 0;     // Rotation angle in radiant
+  bool validRotAngle = false;   // Valid flag magnet present for rotation sensor
+  struct tm rtcTime;            // UTC time from internal RTC
+  bool rtcValid = false;
   int sunsetHour = 0;
   int sunsetMinute = 0;
   int sunriseHour = 0;
@@ -169,13 +165,16 @@ class PageStruct{
         PageDescription *description=NULL;
 };
 
-// Structure for formated boat values
+// Standard format functions without overhead
+String formatDate(String fmttype, uint16_t year, uint8_t month, uint8_t day);
+String formatTime(char fmttype, uint8_t hour, uint8_t minute, uint8_t second);
+
+// Structure for formatted boat values
 typedef struct{
   double value;
   String svalue;
   String unit;
 } FormatedData;
 
-
-// Formater for boat values
+// Formatter for boat values
 FormatedData formatValue(GwApi::BoatValue *value, CommonData &commondata);
diff --git a/lib/obp60task/config.json b/lib/obp60task/config.json
index 14d313a..44db864 100644
--- a/lib/obp60task/config.json
+++ b/lib/obp60task/config.json
@@ -8,6 +8,17 @@
         "description": "system name, used for the access point and for services",
         "category": "system"
     },
+    {
+        "name": "timeServer",
+        "label": "time server",
+        "type": "string",
+        "default": "pool.ntp.org",
+        "description": "NTP time server. Use only one hostname or IP address",
+        "category": "wifi client",
+        "capabilities": {
+            "obp40": "true"
+        }
+    },
     {
         "name": "timeZone",
         "label": "Time Zone",
@@ -22,6 +33,34 @@
             "obp60":"true"
         }
     },
+    {
+        "name": "homeLAT",
+        "label": "Home latitude",
+        "type": "number",
+        "default": "",
+        "check": "checkMinMax",
+        "min": -90.0,
+        "max": 90.0,
+        "description": "Latitude of boat home location [-90.0...+90.0]",
+        "category": "OBP60 Settings",
+        "capabilities": {
+            "obp60":"true"
+        }
+    },
+    {
+        "name": "homeLON",
+        "label": "Home longitude",
+        "type": "number",
+        "default": "",
+        "check": "checkMinMax",
+        "min": -180.0,
+        "max": 180.0,
+        "description": "Longitude of boat home location [-180.0...+180.0]",
+        "category": "OBP60 Settings",
+        "capabilities": {
+            "obp60":"true"
+        }
+    },
     {
         "name": "draft",
         "label": "Boat Draft [m]",
@@ -690,6 +729,21 @@
             "obp60":"true"
         }
     },
+    {
+        "name": "timeSource",
+        "label": "Status Time Source",
+        "type": "list",
+        "default": "GPS",
+        "description": "Data source for date and time display in status line [RTC|GPS]",
+        "list": [
+            {"l":"Real time clock (RTC)","v":"RTC"},
+            {"l":"Time via bus (GPS)","v":"GPS"}
+        ],
+        "category": "OBP60 Display",
+        "capabilities": {
+            "obp60":"true"
+        }
+    },
     {
         "name": "refresh",
         "label": "Refresh",
diff --git a/lib/obp60task/config_obp40.json b/lib/obp60task/config_obp40.json
index 888c746..e24e9e9 100644
--- a/lib/obp60task/config_obp40.json
+++ b/lib/obp60task/config_obp40.json
@@ -8,6 +8,17 @@
         "description": "system name, used for the access point and for services",
         "category": "system"
     },
+    {
+        "name": "timeServer",
+        "label": "time server",
+        "type": "string",
+        "default": "pool.ntp.org",
+        "description": "NTP time server. Use only one hostname or IP address",
+        "category": "wifi client",
+        "capabilities": {
+            "obp40": "true"
+        }
+    },
     {
         "name": "timeZone",
         "label": "Time Zone",
@@ -22,6 +33,34 @@
             "obp40": "true"
         }
     },
+    {
+        "name": "homeLAT",
+        "label": "Home latitude",
+        "type": "number",
+        "default": "0.00000",
+        "check": "checkMinMax",
+        "min": -90.0,
+        "max": 90.0,
+        "description": "Latitude of boat home location [-90.0...+90.0]",
+        "category": "OBP40 Settings",
+        "capabilities": {
+            "obp40": "true"
+        }
+    },
+    {
+        "name": "homeLON",
+        "label": "Home longitude",
+        "type": "number",
+        "default": "0.00000",
+        "check": "checkMinMax",
+        "min": -180.0,
+        "max": 180.0,
+        "description": "Longitude of boat home location [-180.0...+180.0]",
+        "category": "OBP40 Settings",
+        "capabilities": {
+            "obp40": "true"
+        }
+    },
     {
         "name": "draft",
         "label": "Boat Draft [m]",
@@ -705,6 +744,22 @@
             "obp40": "true"
         }
     },
+    {
+        "name": "timeSource",
+        "label": "Status Time Source",
+        "type": "list",
+        "default": "GPS",
+        "description": "Data source for date and time display in status line [RTC|iRTC|GPS]",
+        "list": [
+            {"l":"Internal real time clock (iRTC)","v":"iRTC"},
+            {"l":"External real time clock (RTC)","v":"RTC"},
+            {"l":"External time via bus (GPS)","v":"GPS"}
+        ],
+        "category": "OBP40 Display",
+        "capabilities": {
+            "obp40":"true"
+        }
+    },
     {
         "name": "refresh",
         "label": "Refresh",
diff --git a/lib/obp60task/obp60task.cpp b/lib/obp60task/obp60task.cpp
index d92454b..8a65aac 100644
--- a/lib/obp60task/obp60task.cpp
+++ b/lib/obp60task/obp60task.cpp
@@ -548,7 +548,7 @@ void OBP60Task(GwApi *api){
     // Configuration values for main loop
     String gpsFix = api->getConfig()->getConfigItem(api->getConfig()->flashLED,true)->asString();
     String gpsOn=api->getConfig()->getConfigItem(api->getConfig()->useGPS,true)->asString();
-    String tz = api->getConfig()->getConfigItem(api->getConfig()->timeZone,true)->asString();
+    float tz = api->getConfig()->getConfigItem(api->getConfig()->timeZone,true)->asFloat();
 
     commonData.backlight.mode = backlightMapping(config->getConfigItem(config->backlight,true)->asString());
     commonData.backlight.color = colorMapping(config->getConfigItem(config->blColor,true)->asString());
@@ -559,6 +559,15 @@ void OBP60Task(GwApi *api){
     String cpuspeed = api->getConfig()->getConfigItem(api->getConfig()->cpuSpeed,true)->asString();
     uint hdopAccuracy = uint(api->getConfig()->getConfigItem(api->getConfig()->hdopAccuracy,true)->asInt());
 
+    double homelat = commonData.config->getString(commonData.config->homeLAT).toDouble();
+    double homelon = commonData.config->getString(commonData.config->homeLON).toDouble();
+    bool homevalid = homelat >= -180.0 and homelat <= 180 and homelon >= -90.0 and homelon <= 90.0;
+    if (homevalid) {
+        LOG_DEBUG(GwLog::LOG, "Home location set to %f : %f", homelat, homelon);
+    } else {
+        LOG_DEBUG(GwLog::LOG, "No valid home location found");
+    }
+
     // refreshmode defined in init section
 
     // Boat values for main loop
@@ -708,7 +717,7 @@ void OBP60Task(GwApi *api){
                 starttime5 = millis();
                 if(time->valid == true && date->valid == true && lat->valid == true && lon->valid == true){
                     // Provide sundata to all pages
-                    commonData.sundata = calcSunsetSunrise(api, time->value , date->value, lat->value, lon->value, tz.toDouble());
+                    commonData.sundata = calcSunsetSunrise(time->value , date->value, lat->value, lon->value, tz);
                     // Backlight with sun control
                     if (commonData.backlight.mode == BacklightMode::SUN) {
                     // if(String(backlight) == "Control by Sun"){
@@ -719,6 +728,9 @@ void OBP60Task(GwApi *api){
                             setBacklightLED(0, COLOR_BLUE); // Backlight LEDs off (blue without britghness)
                         }
                     }
+                } else if (homevalid and commonData.data.rtcValid) {
+                    // No gps fix but valid home location and time configured
+                    commonData.sundata = calcSunsetSunriseRTC(&commonData.data.rtcTime, homelat, homelon, tz);
                 }
             }
             
diff --git a/lib/obp60task/platformio.ini b/lib/obp60task/platformio.ini
index 2259b61..4acd552 100644
--- a/lib/obp60task/platformio.ini
+++ b/lib/obp60task/platformio.ini
@@ -21,6 +21,7 @@ lib_deps =
     ${basedeps.lib_deps}
     Wire
     SPI
+    ESP32time
     esphome/AsyncTCP-esphome@2.0.1
     robtillaart/PCF8574@0.3.9
     adafruit/Adafruit Unified Sensor @ 1.1.13
@@ -71,6 +72,7 @@ lib_deps =
     Wire
     SPI
     SD
+    ESP32time
     esphome/AsyncTCP-esphome@2.0.1
     robtillaart/PCF8574@0.3.9
     adafruit/Adafruit Unified Sensor @ 1.1.13
@@ -94,8 +96,8 @@ build_flags=
     -D DISABLE_DIAGNOSTIC_OUTPUT    #Disable diagnostic output for GxEPD2 lib
     -D BOARD_OBP40S3                #Board OBP40 V1.0 with ESP32S3 SKU:DIE07300S (CrowPanel 4.2)
     -D DISPLAY_GDEY042T81           #new E-Ink display from Waveshare, R10 2.2 ohm
-    -D LIPO_ACCU_1200               #Hardware extension, LiPo accu 3,7V 1200mAh
-    -D VOLTAGE_SENSOR               #Hardware extension, LiPo voltage sensor with two resistors 
+    #-D LIPO_ACCU_1200               #Hardware extension, LiPo accu 3,7V 1200mAh
+    #-D VOLTAGE_SENSOR               #Hardware extension, LiPo voltage sensor with two resistors
     ${env.build_flags}
 upload_port = /dev/ttyUSB0          #OBP40 download via external USB/Serail converter
 upload_protocol = esptool           #firmware upload via USB OTG seriell, by first upload need to set the ESP32-S3 in the upload mode with shortcut GND to Pin27