diff --git a/libraries/AP_GPS/GPS_Backend.cpp b/libraries/AP_GPS/GPS_Backend.cpp
index ae60f9631a..84a487642c 100644
--- a/libraries/AP_GPS/GPS_Backend.cpp
+++ b/libraries/AP_GPS/GPS_Backend.cpp
@@ -114,8 +114,8 @@ void AP_GPS_Backend::make_gps_time(uint32_t bcd_date, uint32_t bcd_milliseconds)
         // gcs().send_text(MAV_SEVERITY_INFO, "week:%d,ms:%ld",state.time_week,state.time_week_ms);
         // gcs().send_text(MAV_SEVERITY_INFO, "year:%d,m:%d,d:%d \n\r",tm.tm_year,tm.tm_mon,tm.tm_mday);
         // gcs().send_text(MAV_SEVERITY_INFO, "hour:%d,m:%d,s:%d \n\r",tm.tm_hour,tm.tm_min,tm.tm_sec);
-        gcs().send_text(MAV_SEVERITY_INFO, "unix_time:%ld\n\r",unix_time);
-        
+        gcs().send_text(MAV_SEVERITY_INFO, "unix_time:%ld",unix_time);
+        gcs().send_text(MAV_SEVERITY_INFO,"now: %s\n",AP::rtc().get_rtc_date());
         last_1s = AP_HAL::millis();
     }
 }
diff --git a/libraries/AP_Logger/AP_Logger_File.cpp b/libraries/AP_Logger/AP_Logger_File.cpp
index bd8e8579c2..d4f6e67857 100644
--- a/libraries/AP_Logger/AP_Logger_File.cpp
+++ b/libraries/AP_Logger/AP_Logger_File.cpp
@@ -824,6 +824,8 @@ void AP_Logger_File::start_new_log(void)
     uint64_t utc_usec;
     _need_rtc_update = !AP::rtc().get_utc_usec(utc_usec);
     gcs().send_text(MAV_SEVERITY_INFO, "log utc {%d}:%lld\n",_need_rtc_update,utc_usec);
+    
+        gcs().send_text(MAV_SEVERITY_INFO,"log date:%s",AP::rtc().get_rtc_date());
 #endif
 
     // create the log directory if need be
diff --git a/libraries/AP_RTC/AP_RTC.cpp b/libraries/AP_RTC/AP_RTC.cpp
index aa646cb9dd..319dc7060b 100644
--- a/libraries/AP_RTC/AP_RTC.cpp
+++ b/libraries/AP_RTC/AP_RTC.cpp
@@ -4,6 +4,7 @@
 #include <AP_Math/AP_Math.h>
 #include <GCS_MAVLink/GCS.h>
 #include <time.h>
+#include <stdio.h>
 
 extern const AP_HAL::HAL& hal;
 
@@ -41,20 +42,40 @@ const AP_Param::GroupInfo AP_RTC::var_info[] = {
 
 void AP_RTC::set_utc_usec(uint64_t time_utc_usec, source_type type)
 {
+    bool need_prt = false;
+    static uint32_t last_1s = AP_HAL::millis();
+    if (AP_HAL::millis() - last_1s > 5000)
+    {
+        need_prt = true;
+        last_1s = AP_HAL::millis();
+    }
+    //////////////////////////////////////
     const uint64_t oldest_acceptable_date_us = 1640995200ULL*1000*1000; // 2022-01-01 0:00
 
     if (type >= rtc_source_type) {
         // e.g. system-time message when we've been set by the GPS
+        if (need_prt)
+        {
+            gcs().send_text(MAV_SEVERITY_INFO, "type{%d} >= rtc_source_type{%d}",type , (uint8_t)rtc_source_type);
+        }
         return;
     }
 
     // check it's from an allowed sources:
     if (!(allowed_types & (1<<type))) {
+        if (need_prt)
+        {
+            gcs().send_text(MAV_SEVERITY_INFO, "!(allowed_types{%d}& (1<<type{%d}))",(uint8_t)allowed_types,(uint8_t)type);
+        }
         return;
     }
 
     // don't allow old times
     if (time_utc_usec < oldest_acceptable_date_us) {
+        if (need_prt)
+        {
+            gcs().send_text(MAV_SEVERITY_INFO, "time_utc_usec < oldest_acceptable_date_us");
+        }
         return;
     }
 
@@ -62,6 +83,10 @@ void AP_RTC::set_utc_usec(uint64_t time_utc_usec, source_type type)
     const int64_t tmp = int64_t(time_utc_usec) - int64_t(now);
     if (tmp < rtc_shift) {
         // can't allow time to go backwards, ever
+        if (need_prt)
+        {
+            gcs().send_text(MAV_SEVERITY_INFO, "tmp{%lld} < rtc_shift{%lld}",tmp , rtc_shift);
+        }
         return;
     }
     WITH_SEMAPHORE(rsem);
@@ -75,6 +100,10 @@ void AP_RTC::set_utc_usec(uint64_t time_utc_usec, source_type type)
 
     rtc_source_type = type;
 
+    if (need_prt)
+    {
+        gcs().send_text(MAV_SEVERITY_INFO, "type:%d,in utc:%lld,rtc_shift:%lld",type,time_utc_usec,rtc_shift);
+    }
 #if HAL_GCS_ENABLED
     // update signing timestamp
     GCS_MAVLINK::update_signing_timestamp(time_utc_usec);
@@ -205,6 +234,26 @@ uint32_t AP_RTC::get_time_utc(int32_t hour, int32_t min, int32_t sec, int32_t ms
     return static_cast<uint32_t>(total_delay_ms);
 }
 
+char* AP_RTC::get_rtc_date(void)
+{
+    uint16_t year;uint8_t mon;uint8_t mday;uint8_t hour; uint8_t min; uint8_t sec;
+    tm localtime_tm {}; // year is relative to 1900
+    uint64_t time_usec = 0;
+    if (get_utc_usec(time_usec)) { // may fail, leaving time_unix at 0
+        const time_t time_sec = time_usec / 1000000;
+        localtime_tm = *gmtime(&time_sec);
+    }
+
+    year = uint16_t(localtime_tm.tm_year + 1900);   // tm_year is relative to year 1900
+    mon = uint8_t(localtime_tm.tm_mon + 1);        // MSP requires [1-12] months
+    mday = uint8_t(localtime_tm.tm_mday);
+    hour = uint8_t(localtime_tm.tm_hour);
+    min = uint8_t(localtime_tm.tm_min);
+    sec = uint8_t(localtime_tm.tm_sec);
+    static char  buf[50];
+    snprintf(buf, sizeof(buf),  "%04d%02d%02d%02d%02d%02d",year,mon,mday,hour,min,sec);
+    return buf;
+}
 
 /*
   mktime replacement from Samba
diff --git a/libraries/AP_RTC/AP_RTC.h b/libraries/AP_RTC/AP_RTC.h
index 984a409e41..dce33972b7 100644
--- a/libraries/AP_RTC/AP_RTC.h
+++ b/libraries/AP_RTC/AP_RTC.h
@@ -51,6 +51,7 @@ public:
     static AP_RTC *get_singleton() {
         return _singleton;
     }
+    char* get_rtc_date(void);
 
     // allow threads to lock against RTC update
     HAL_Semaphore &get_semaphore(void) {