 
     // connect to wifi
     Serial.println("Starting WIFI manager ...");
+    wifiManager.setConfigPortalTimeout(120);
     wifiManager.autoConnect("ESP-GEIGER");
 
     // start counting

    attachInterrupt(digitalPinToInterrupt(PIN_TICK), tube_impulse, FALLING); 
}

static void mqtt_send(const char *topic, const char *value)
{
    if (!mqttClient.connected()) {
        mqttClient.setServer(MQTT_HOST, MQTT_PORT);
        mqttClient.connect(esp_id);
    }
    if (mqttClient.connected()) {
        Serial.print("Publishing ");

        // send over MQTT
        char message[16];
        snprintf(message, sizeof(message), "%d cpm", cpm);
        mqtt_send(TOPIC_GEIGER, message, true);

        // verify network connection and reboot on failure
        if (WiFi.status() != WL_CONNECTED) {
            Serial.println("Restarting ESP...");
            ESP.restart();
        }
    }

    // keep MQTT alive
