         }
         radio.read(&sensor_data, sizeof(sensor_data));
 
-        if ( sensor_data.devid != 15 ) {
+        //if ( sensor_data.devid != 15 ) {
+        if ( pipeNo == 1 && sensor_data.devid != 15 ) {
+          if ( sensor_data.devid != 2 ) {
+            radio.writeAckPayload(pipeNo, &time_ackpayload, sizeof(time_ackpayload));
+          }
+          
           String radiopayload = "{\"_salt\":";
           radiopayload += sensor_data._salt;
           radiopayload += ",\"volt\":";

}

void loop() {
  if (WiFi.status() == WL_CONNECTED) {
    if (!client.connected()) {
      if (DEBUG_PRINT) {

#include <ESP8266mDNS.h>
#include <ArduinoOTA.h>
#include <WiFiUdp.h>

// radio
#define DEVICE_ID 1
