diff --git a/Release/view1090.exe b/Release/view1090.exe
index 2a879c5..db55062 100644
Binary files a/Release/view1090.exe and b/Release/view1090.exe differ
diff --git a/coaa1090.obj b/coaa1090.obj
index 7e35631..845210c 100644
Binary files a/coaa1090.obj and b/coaa1090.obj differ
diff --git a/dump1090.c b/dump1090.c
index 70a4d04..b8ec611 100644
--- a/dump1090.c
+++ b/dump1090.c
@@ -69,6 +69,7 @@ void modesInitConfig(void) {
     Modes.gain                    = MODES_MAX_GAIN;
     Modes.freq                    = MODES_DEFAULT_FREQ;
     Modes.check_crc               = 1;
+    Modes.net_heartbeat_rate      = MODES_NET_HEARTBEAT_RATE;
     Modes.net_output_sbs_port     = MODES_NET_OUTPUT_SBS_PORT;
     Modes.net_output_raw_port     = MODES_NET_OUTPUT_RAW_PORT;
     Modes.net_input_raw_port      = MODES_NET_INPUT_RAW_PORT;
@@ -412,6 +413,7 @@ void showHelp(void) {
 "--net-bo-port <port>     TCP Beast output listen port (default: 30005)\n"
 "--net-ro-size <size>     TCP raw output minimum size (default: 0)\n"
 "--net-ro-rate <rate>     TCP raw output memory flush rate (default: 0)\n"
+"--net-heartbeat <rate>   TCP heartbeat rate in seconds (default: 60 sec)\n"
 "--lat <latitude>         Reference/receiver latitude for surface posn (opt)\n"
 "--lon <longitude>        Reference/receiver longitude for surface posn (opt)\n"
 "--fix                    Enable single-bits error correction using CRC\n"
@@ -503,7 +505,9 @@ int main(int argc, char **argv) {
         } else if (!strcmp(argv[j],"--net-only")) {
             Modes.net = 1;
             Modes.net_only = 1;
-        } else if (!strcmp(argv[j],"--net-ro-size") && more) {
+       } else if (!strcmp(argv[j],"--net-heartbeat") && more) {
+            Modes.net_heartbeat_rate = atoi(argv[++j]) * 15;
+       } else if (!strcmp(argv[j],"--net-ro-size") && more) {
             Modes.net_output_raw_size = atoi(argv[++j]);
         } else if (!strcmp(argv[j],"--net-ro-rate") && more) {
             Modes.net_output_raw_rate = atoi(argv[++j]);
diff --git a/dump1090.h b/dump1090.h
index 28d7cf3..68bc6d9 100644
--- a/dump1090.h
+++ b/dump1090.h
@@ -37,7 +37,7 @@
 // MinorVer changes when additional features are added, but not for bug fixes (range 00-99)
 // DayDate & Year changes for all changes, including for bug fixes. It represent the release date of the update
 //
-#define MODES_DUMP1090_VERSION     "1.08.2302.14"
+#define MODES_DUMP1090_VERSION     "1.08.1003.14"
 
 // ============================= Include files ==========================
 
@@ -163,6 +163,8 @@
 #define MODES_INTERACTIVE_DELETE_TTL   300      // Delete from the list after 300 seconds
 #define MODES_INTERACTIVE_DISPLAY_TTL   60      // Delete from display after 60 seconds
 
+#define MODES_NET_HEARTBEAT_RATE       900      // Each block is approx 65mS - default is > 1 min
+
 #define MODES_NET_SERVICES_NUM          6
 #define MODES_NET_MAX_FD             1024
 #define MODES_NET_INPUT_RAW_PORT    30001
@@ -281,6 +283,8 @@ struct {                             // Internal state
     int   debug;                     // Debugging mode
     int   net;                       // Enable networking
     int   net_only;                  // Enable just networking
+    int   net_heartbeat_count;       // TCP heartbeat counter
+    int   net_heartbeat_rate;        // TCP heartbeat rate
     int   net_output_sbs_port;       // SBS output TCP port
     int   net_output_raw_size;       // Minimum Size of the output raw data
     int   net_output_raw_rate;       // Rate (in 64mS increments) of output raw data
diff --git a/mode_s.c b/mode_s.c
index 84bef2d..e5e9c81 100644
--- a/mode_s.c
+++ b/mode_s.c
@@ -1812,6 +1812,25 @@ void detectModeS(uint16_t *m, uint32_t mlen) {
         Modes.net_output_raw_rate_count = 0;
         }
       }
+    else if ( (Modes.net) 
+           && (Modes.net_heartbeat_rate) 
+           && ((++Modes.net_heartbeat_count) > Modes.net_heartbeat_rate) ) {
+      //
+      // We haven't received any Mode A/C/S messages for some time. To try and keep any TCP
+      // links alive, send a null frame. This will help stop any routers discarding our TCP 
+      // link which will cause an un-recoverable link error if/when a real frame arrives.   
+      //
+      // Fudge up a null message
+      memset(&mm, 0, sizeof(mm));
+      mm.msgbits      = MODES_SHORT_MSG_BITS;
+      mm.timestampMsg = Modes.timestampBlk;
+
+      // Feed output clients
+      modesQueueOutput(&mm);
+
+      // Reset the heartbeat counter
+      Modes.net_heartbeat_count = 0;
+      }
 }
 //
 //=========================================================================
@@ -1836,6 +1855,9 @@ void useModesMessage(struct modesMessage *mm) {
 
         // Feed output clients
         if (Modes.net) {modesQueueOutput(mm);}
+
+        // Heartbeat not required whilst we're seeing real messages
+        Modes.net_heartbeat_count = 0;
     }
 }
 //