diff --git a/RemoteIDModule/BLE_TX.cpp b/RemoteIDModule/BLE_TX.cpp
index 97a869e..a89458e 100644
--- a/RemoteIDModule/BLE_TX.cpp
+++ b/RemoteIDModule/BLE_TX.cpp
@@ -91,7 +91,7 @@ bool BLE_TX::init(void)
     if (initialised) {
         return true;
     }
-    initialised = true;
+    
     BLEDevice::init("");
 
     // setup power levels
@@ -111,20 +111,22 @@ bool BLE_TX::init(void)
     // set as a bluetooth random static address
     mac_addr[0] |= 0xc0;
 
-    advert.setAdvertisingParams(0, &legacy_adv_params);
-    advert.setInstanceAddress(0, mac_addr);
+    if (!advert.setAdvertisingParams(0, &legacy_adv_params)) { return false; }
+    if (!advert.setInstanceAddress(0, mac_addr)) { return false; }
     advert.setDuration(0);
 
-    advert.setAdvertisingParams(1, &ext_adv_params_coded);
+    if (!advert.setAdvertisingParams(1, &ext_adv_params_coded)) { return false; }
     advert.setDuration(1);
-    advert.setInstanceAddress(1, mac_addr);
+    if (!advert.setInstanceAddress(1, mac_addr)) { return false; }
 
     // prefer S8 coding
     if (esp_ble_gap_set_prefered_default_phy(ESP_BLE_GAP_PHY_OPTIONS_PREF_S8_CODING, ESP_BLE_GAP_PHY_OPTIONS_PREF_S8_CODING) != ESP_OK) {
         Serial.printf("Failed to setup S8 coding\n");
+        return false;
     }
 
     memset(&msg_counters,0, sizeof(msg_counters));
+    initialised = true;
     return true;
 }
 
@@ -132,7 +134,10 @@ bool BLE_TX::init(void)
 
 bool BLE_TX::transmit_longrange(ODID_UAS_Data &UAS_data)
 {
-    init();
+    if (!init()) {
+        return false;
+    }
+
     // create a packed UAS data message
     uint8_t payload[250];
     int length = odid_message_build_pack(&UAS_data, payload, 255);
@@ -148,11 +153,15 @@ bool BLE_TX::transmit_longrange(ODID_UAS_Data &UAS_data)
     memcpy(&longrange_payload[sizeof(header)], payload, length);
     int longrange_length = sizeof(header) + length;
 
-    advert.setAdvertisingData(1, longrange_length, longrange_payload);
+    if (!advert.setAdvertisingData(1, longrange_length, longrange_payload)) {
+        return false;
+    }
 
     // we start advertising when we have the first lot of data to send
     if (!started) {
-        advert.start();
+        if (!advert.start()) {
+            return false;
+        }
     }
     started = true;
 
@@ -161,7 +170,10 @@ bool BLE_TX::transmit_longrange(ODID_UAS_Data &UAS_data)
 
 bool BLE_TX::transmit_legacy(ODID_UAS_Data &UAS_data)
 {
-    init();
+    if (!init()) { 
+        return false; 
+    }
+
     static uint8_t legacy_phase = 0;
     int legacy_length = 0;
     // setup ASTM header
@@ -307,10 +319,14 @@ bool BLE_TX::transmit_legacy(ODID_UAS_Data &UAS_data)
         legacy_phase %= 6;
     }
 
-    advert.setAdvertisingData(0, legacy_length, legacy_payload);
+    if (!advert.setAdvertisingData(0, legacy_length, legacy_payload)) {
+        return false;
+    }
 
     if (!started) {
-        advert.start();
+        if (!advert.start()) {
+            return false;
+        }
     }
     started = true;
 
diff --git a/RemoteIDModule/RemoteIDModule.ino b/RemoteIDModule/RemoteIDModule.ino
index fd3bcd7..8fc9fb1 100644
--- a/RemoteIDModule/RemoteIDModule.ino
+++ b/RemoteIDModule/RemoteIDModule.ino
@@ -326,6 +326,7 @@ static void set_data(Transport &t)
 
     const char *reason = check_parse();
     t.arm_status_check(reason);
+    if (reason == nullptr && !pfst_check_ok) { reason = "pfst failed"; }
     t.set_parse_fail(reason);
 
     arm_check_ok = (reason==nullptr);
@@ -334,7 +335,7 @@ static void set_data(Transport &t)
         arm_check_ok = true;
     }
 
-    led.set_state(pfst_check_ok && arm_check_ok? Led::LedState::ARM_OK : Led::LedState::ARM_FAIL);
+    led.set_state(arm_check_ok? Led::LedState::ARM_OK : Led::LedState::ARM_FAIL);
 
     uint32_t now_ms = millis();
     uint32_t location_age_ms = now_ms - t.get_last_location_ms();
@@ -416,30 +417,46 @@ void loop()
     static uint32_t last_update_wifi_nan_ms;
     if (g.wifi_nan_rate > 0 &&
         now_ms - last_update_wifi_nan_ms > 1000/g.wifi_nan_rate) {
-        last_update_wifi_nan_ms = now_ms;
-        wifi.transmit_nan(UAS_data);
+        if (wifi.transmit_nan(UAS_data)) {
+            last_update_wifi_nan_ms = now_ms;
+        }
     }
 
     static uint32_t last_update_wifi_beacon_ms;
     if (g.wifi_beacon_rate > 0 &&
         now_ms - last_update_wifi_beacon_ms > 1000/g.wifi_beacon_rate) {
-        last_update_wifi_beacon_ms = now_ms;
-        wifi.transmit_beacon(UAS_data);
+        if(wifi.transmit_beacon(UAS_data)) {
+            last_update_wifi_beacon_ms = now_ms;
+        }
     }
 
     static uint32_t last_update_bt5_ms;
     if (g.bt5_rate > 0 &&
         now_ms - last_update_bt5_ms > 1000/g.bt5_rate) {
-        last_update_bt5_ms = now_ms;
-        ble.transmit_longrange(UAS_data);
+        if(ble.transmit_longrange(UAS_data)) {
+            last_update_bt5_ms = now_ms;
+        }
     }
 
     static uint32_t last_update_bt4_ms;
     int bt4_states = UAS_data.BasicIDValid[1] ? 7 : 6;
     if (g.bt4_rate > 0 &&
         now_ms - last_update_bt4_ms > (1000.0f/bt4_states)/g.bt4_rate) {
-        last_update_bt4_ms = now_ms;
-        ble.transmit_legacy(UAS_data);
+        if(ble.transmit_legacy(UAS_data)) {
+            last_update_bt4_ms = now_ms;
+        }
+    }
+
+    if (now_ms - last_update_wifi_nan_ms > 5000.0 &&
+        now_ms - last_update_wifi_beacon_ms > 5000.0 &&
+        (now_ms - last_update_bt5_ms > 5000.0 ||
+        now_ms - last_update_bt4_ms > 5000.0)) {
+        // transmitter failure
+        pfst_check_ok = false;
+    
+    } else {
+        // transmitter is healthy if wifi nan or wifi beacon or both Bluetooth transmissions work successfully
+        pfst_check_ok = true;
     }
 
     // sleep for a bit for power saving
diff --git a/RemoteIDModule/WiFi_TX.cpp b/RemoteIDModule/WiFi_TX.cpp
index 6cf06db..c173d2b 100644
--- a/RemoteIDModule/WiFi_TX.cpp
+++ b/RemoteIDModule/WiFi_TX.cpp
@@ -15,7 +15,6 @@ bool WiFi_TX::init(void)
     if (initialised) {
         return true;
     }
-    initialised = true;
 
     //use a local MAC address to avoid tracking transponders based on their MAC address
     uint8_t mac_addr[6];
@@ -25,12 +24,18 @@ bool WiFi_TX::init(void)
     mac_addr[0] &= 0xFE;  // unset MAC multicast bit
 
     //set MAC address
-    esp_base_mac_addr_set(mac_addr);
+    if (esp_base_mac_addr_set(mac_addr) != ESP_OK) {
+        return false;
+    }
 
     if (g.webserver_enable == 0) {
-        WiFi.softAP(g.wifi_ssid, g.wifi_password, g.wifi_channel, false, 0); //make it visible and allow no connection
+        if (!WiFi.softAP(g.wifi_ssid, g.wifi_password, g.wifi_channel, false, 0) /* make it visible and allow no connection */ ) { 
+            return false;
+        }
     } else {
-        WiFi.softAP(g.wifi_ssid, g.wifi_password, g.wifi_channel, false, 1); //make it visible and allow only 1 connection
+        if (!WiFi.softAP(g.wifi_ssid, g.wifi_password, g.wifi_channel, false, 1) /* make it visible and allow only 1 connection */ ) {
+            return false;
+        }
     }
 
     if (esp_wifi_set_bandwidth(WIFI_IF_AP, WIFI_BW_HT20) != ESP_OK) {
@@ -39,14 +44,20 @@ bool WiFi_TX::init(void)
 
     memcpy(WiFi_mac_addr,mac_addr,6); //use generated random MAC address for OpenDroneID messages
 
-    esp_wifi_set_max_tx_power(dBm_to_tx_power(g.wifi_power));
+    if (esp_wifi_set_max_tx_power(dBm_to_tx_power(g.wifi_power)) != ESP_OK) {
+        return false;
+    }
+
+    initialised = true;
 
     return true;
 }
 
 bool WiFi_TX::transmit_nan(ODID_UAS_Data &UAS_data)
 {
-    init();
+    if (!init()) {
+        return false;
+    }
 
     uint8_t buffer[1024] {};
 
@@ -72,7 +83,9 @@ bool WiFi_TX::transmit_nan(ODID_UAS_Data &UAS_data)
 //update the payload of the beacon frames in this function
 bool WiFi_TX::transmit_beacon(ODID_UAS_Data &UAS_data)
 {
-    init();
+    if (!init()) {
+        return false;
+    }
 
     uint8_t buffer[1024] {};