diff --git a/RX_FSK/RX_FSK.ino b/RX_FSK/RX_FSK.ino
index 6d5435b..b4c3d9c 100644
--- a/RX_FSK/RX_FSK.ino
+++ b/RX_FSK/RX_FSK.ino
@@ -60,7 +60,7 @@ WiFiClient client;
 WiFiClient shclient;	// Sondehub v2
 unsigned long time_last_update = 0;
 /* SH_LOC_OFF: never send position information to SondeHub
-   SH_LOC_FIXED: send fixed position (if specified in config) or GPS position (if there is a GPS fix) as fixed station position (no chase mode) to sondehub
+   SH_LOC_FIXED: send fixed position (if specified in config) to sondehub
    SH_LOC_CHASE: always activate chase mode and send GPS position (if available)
    SH_LOC_AUTO: if there is no valid GPS position, or GPS position < MIN_LOC_AUTO_DIST away from known fixed position: use FIXED mode
                 otherwise, i.e. if there is a valid GPS position and (either no fixed position in config, or GPS position is far away from fixed position), use CHASE mode.
@@ -3115,40 +3115,52 @@ void sondehub_station_update(WiFiClient *client, struct st_sondehub *conf) {
           "{"
           "\"software_name\": \"%s\","
           "\"software_version\": \"%s\","
-          "\"uploader_callsign\": \"%s\","
-          "\"uploader_contact_email\": \"%s\",",
-          version_name, version_id, conf->callsign, conf->email);
+          "\"uploader_callsign\": \"%s\",",
+          version_name, version_id, conf->callsign);
   w += strlen(w);
 
-  // We send GPS position: (a) in CHASE mode, (b) in FIXED mode if no fixed location has been specified in config
-  if (chase == SH_LOC_CHASE || (chase == SH_LOC_FIXED && (isnan(conf->lat) || isnan(conf->lon)) ) ) {
+  // Only send email if provided
+  if (conf->email != '\0') {
+    sprintf(w,
+          "\"uploader_contact_email\": \"%s\",",
+          conf->email);
+    w += strlen(w);
+  }
+
+  // Only send antenna if provided
+  if (conf->antenna != '\0') {
+    sprintf(w,
+          "\"uploader_antenna\": \"%s\",",
+          conf->antenna);
+    w += strlen(w);
+  }
+
+  // We send GPS position: (a) in CHASE mode, (b) in AUTO mode if no fixed location has been specified in config
+  if (chase == SH_LOC_CHASE) {
     if (gpsPos.valid && gpsPos.lat != 0 && gpsPos.lon != 0) {
       sprintf(w,
               "\"uploader_position\": [%.6f,%.6f,%d],"
-              "\"uploader_antenna\": \"%s\","
-              "\"mobile\": true"
-              "}",
-              gpsPos.lat, gpsPos.lon, gpsPos.alt, conf->antenna);
+              "\"mobile\": true",
+              gpsPos.lat, gpsPos.lon, gpsPos.alt);
+    } else {
+      sprintf(w, "\"uploader_position\": [null,null,null]");
     }
+    w += strlen(w);
   }
   // Otherweise, in FIXED mode we send the fixed position from config (if specified)
   else if (chase == SH_LOC_FIXED) {
     if ((!isnan(conf->lat)) && (!isnan(conf->lon))) {
       sprintf(w,
-              "\"uploader_position\": [%.6f,%.6f,%s],"
-              "\"uploader_antenna\": \"%s\""
-              "}",
-              conf->lat, conf->lon, conf->alt[0] ? conf->alt : "null", conf->antenna);
+              "\"uploader_position\": [%.6f,%.6f,%s]",
+              conf->lat, conf->lon, conf->alt[0] ? conf->alt : "null");
+    } else {
+      sprintf(w, "\"uploader_position\": [null,null,null]");
     }
+    w += strlen(w);
   }
-  else {
-    // otherwise (in SH_LOC_NONE mode) we dont include any position info
-     sprintf(w,
-              "\"uploader_position\": [null,null,null],"
-              "\"uploader_antenna\": \"%s\""
-              "}",
-              conf->antenna);
-  }
+
+  // otherwise (in SH_LOC_NONE mode) we dont include any position info
+  sprintf(w, "}");
 
   client->println("PUT /listeners HTTP/1.1");
   client->print("Host: ");
@@ -3210,6 +3222,12 @@ void sondehub_send_data(WiFiClient * client, SondeInfo * s, struct st_sondehub *
   // For all others, sec should always be 0 and time the exact time in seconds
   time_t t = s->time;
 
+  int chase = conf->chase;
+  // automatically decided if CHASE or FIXED mode is used (for config AUTO)
+  if (chase == SH_LOC_AUTO) {
+    if (SH_LOC_AUTO_IS_CHASE) chase = SH_LOC_CHASE; else chase = SH_LOC_FIXED;
+  }
+
   while (client->available() > 0) {
     // data is available from remote server, process it...
     int cnt = client->readBytesUntil('\n', rs_msg, MSG_SIZE-1);
@@ -3280,34 +3298,31 @@ void sondehub_send_data(WiFiClient * client, SondeInfo * s, struct st_sondehub *
           "\"manufacturer\": \"%s\","
           "\"serial\": \"%s\","
           "\"datetime\": \"%04d-%02d-%02dT%02d:%02d:%02d.000Z\","
-          "\"lat\": %.6f,"
-          "\"lon\": %.6f,"
-          "\"alt\": %.3f,"
+          "\"lat\": %.5f,"
+          "\"lon\": %.5f,"
+          "\"alt\": %.5f,"
           "\"frequency\": %.3f,"
-          "\"vel_h\": %.3f,"
-          "\"vel_v\": %.3f,"
-          "\"heading\": %.3f,"
-          "\"rssi\": %.1f,",
+          "\"vel_h\": %.5f,"
+          "\"vel_v\": %.5f,"
+          "\"heading\": %.5f,"
+          "\"rssi\": %.1f,"
+          "\"frame\": %d,"
+          "\"type\": \"%s\",",
           version_name, version_id, conf->callsign,
           timeinfo.tm_year + 1900, timeinfo.tm_mon + 1, timeinfo.tm_mday, timeinfo.tm_hour, timeinfo.tm_min, timeinfo.tm_sec,
           manufacturer_string[realtype], s->ser,
           ts.tm_year + 1900, ts.tm_mon + 1, ts.tm_mday, ts.tm_hour, ts.tm_min, ts.tm_sec,
           (float)s->lat, (float)s->lon, (float)s->alt, (float)s->freq, (float)s->hs, (float)s->vs,
-          (float)s->dir, -((float)s->rssi / 2)
+          (float)s->dir, -((float)s->rssi / 2), s->vframe, sondeTypeStrSH[realtype]
          );
   w += strlen(w);
 
+  // Only send sats if not M20
   if (realtype != STYPE_M20) {
     sprintf(w, "\"sats\": %d,", (int)s->sats);
     w += strlen(w);
   }
 
-  sprintf(w, "\"frame\": %d,", s->vframe);
-  w += strlen(w);
-
-  sprintf(w, "\"type\": \"%s\",", sondeTypeStrSH[realtype]);
-  w += strlen(w);
-
   /* if there is a subtype (DFM only) */
   if ( TYPE_IS_DFM(s->type) && s->subtype > 0 && s->subtype < 16 ) {
     const char *t = dfmSubtypeStrSH[s->subtype];
@@ -3317,6 +3332,7 @@ void sondehub_send_data(WiFiClient * client, SondeInfo * s, struct st_sondehub *
     w += strlen(w);
   }
 
+  // Only send temp & humidity if provided
   if (((int)s->temperature != 0) && ((int)s->relativeHumidity != 0)) {
     sprintf(w,
             "\"temp\": %.1f,"
@@ -3326,38 +3342,41 @@ void sondehub_send_data(WiFiClient * client, SondeInfo * s, struct st_sondehub *
     w += strlen(w);
   }
 
-  if ((conf->chase == 0) && (!isnan(conf->lat)) && (!isnan(conf->lon))) {
-    if (conf->alt[0] != '\0') {
+  // Only send antenna if provided
+  if (conf->antenna != '\0') {
+    sprintf(w,
+          "\"uploader_antenna\": \"%s\",",
+          conf->antenna);
+    w += strlen(w);
+  }
+
+  // We send GPS position: (a) in CHASE mode, (b) in AUTO mode if no fixed location has been specified in config
+  if (chase == SH_LOC_CHASE) {
+    if (gpsPos.valid && gpsPos.lat != 0 && gpsPos.lon != 0) {
       sprintf(w,
-              "\"uploader_position\": [%.6f,%.6f,%s],"
-              "\"uploader_antenna\": \"%s\""
-              "}",
-              conf->lat, conf->lon, conf->alt, conf->antenna
-             );
+              "\"uploader_position\": [%.6f,%.6f,%d],"
+              "\"mobile\": true",
+              gpsPos.lat, gpsPos.lon, gpsPos.alt);
     } else {
-      sprintf(w,
-              "\"uploader_position\": [%.6f,%.6f,null],"
-              "\"uploader_antenna\": \"%s\""
-              "}",
-              conf->lat, conf->lon, conf->antenna
-             );
+      sprintf(w, "\"uploader_position\": [null,null,null]");
     }
+    w += strlen(w);
   }
-  else if (gpsPos.valid && gpsPos.lat != 0 && gpsPos.lon != 0) {
-    sprintf(w,
-            "\"uploader_position\": [%.6f,%.6f,%d],"
-            "\"uploader_antenna\": \"%s\""
-            "}",
-            gpsPos.lat, gpsPos.lon, gpsPos.alt, conf->antenna
-           );
-  }
-  else {
-    sprintf(w,
-            "\"uploader_antenna\": \"%s\""
-            "}",
-            conf->antenna
-           );
+  // Otherweise, in FIXED mode we send the fixed position from config (if specified)
+  else if (chase == SH_LOC_FIXED) {
+    if ((!isnan(conf->lat)) && (!isnan(conf->lon))) {
+      sprintf(w,
+              "\"uploader_position\": [%.6f,%.6f,%s]",
+              conf->lat, conf->lon, conf->alt[0] ? conf->alt : "null");
+    } else {
+      sprintf(w, "\"uploader_position\": [null,null,null]");
+    }
+    w += strlen(w);
   }
+
+  // otherwise (in SH_LOC_NONE mode) we dont include any position info
+  sprintf(w, "}");
+
   if (shState != SH_CONN_APPENDING) {
     sondehub_send_header(client, s, conf);
     sondehub_send_next(client, s, conf, rs_msg, strlen(rs_msg), 1);
diff --git a/RX_FSK/data/config.txt b/RX_FSK/data/config.txt
index 08ef101..8a8487e 100644
--- a/RX_FSK/data/config.txt
+++ b/RX_FSK/data/config.txt
@@ -121,7 +121,7 @@ mqtt.prefix=rdz_sonde_server/
 #-------------------------------#
 # Sondehub v2 DB settings
 sondehub.active=0
-sondehub.chase=0
+sondehub.chase=2
 sondehub.host=api.v2.sondehub.org
 sondehub.callsign=CHANGEME_RDZTTGO
 sondehub.lat=
diff --git a/RX_FSK/version.h b/RX_FSK/version.h
index 2b47269..4e166f8 100644
--- a/RX_FSK/version.h
+++ b/RX_FSK/version.h
@@ -1,4 +1,4 @@
 const char *version_name = "rdzTTGOsonde";
-const char *version_id = "devel20210912";
+const char *version_id = "devel20210913";
 const int SPIFFS_MAJOR=2;
 const int SPIFFS_MINOR=14;