diff --git a/src/JJYReceiver.cpp b/src/JJYReceiver.cpp
index 16c6cc6..115ce4e 100644
--- a/src/JJYReceiver.cpp
+++ b/src/JJYReceiver.cpp
@@ -13,23 +13,27 @@
   extern SoftwareSerial debugSerial;
 #endif
 
-JJYReceiver::JJYReceiver(int pindata,int pinsel,int pinpon){
+JJYReceiver::JJYReceiver(int pindata,int pinsel,int pinpon) : 
+ datapin(pindata), selpin(pinsel), ponpin(pinpon)
+ {
   pinMode(pindata, INPUT);
   pinMode(pinsel, OUTPUT);
   pinMode(pinpon, OUTPUT);
-  datapin = pindata;
-  selpin = pinsel;
-  ponpin = pinpon;
+  //datapin = pindata;
+  //selpin = pinsel;
+  //ponpin = pinpon;
 }
-JJYReceiver::JJYReceiver(int pindata,int pinpon){
+JJYReceiver::JJYReceiver(int pindata,int pinpon):
+ datapin(pindata), ponpin(pinpon){
   pinMode(pindata, INPUT);
   pinMode(pinpon, OUTPUT);
-  datapin = pindata;
-  ponpin = pinpon;
+  //datapin = pindata;
+  //ponpin = pinpon;
 }
-JJYReceiver::JJYReceiver(int pindata){
+JJYReceiver::JJYReceiver(int pindata):
+ datapin(pindata){
   pinMode(pindata, INPUT);
-  datapin = pindata;
+  //datapin = pindata;
 }
 
 JJYReceiver::~JJYReceiver(){
@@ -243,7 +247,7 @@ uint8_t JJYReceiver::freq(uint8_t freq){
 bool JJYReceiver::power(){
   return (digitalRead(ponpin) == HIGH && digitalRead(selpin) == HIGH) ?  false : true;
 }
-bool JJYReceiver::power(bool power){
+bool JJYReceiver::power(bool powerstate){
   // PDN1(SEL) PDN2(PON)
   // 0 0 freq2 40kHz
   // 0 1 freq2 (non use)
@@ -253,7 +257,7 @@ bool JJYReceiver::power(bool power){
     DEBUG_PRINTLN(selpin);
     DEBUG_PRINTLN(ponpin);
   if(ponpin == -1) return true;
-  if(power == true){
+  if(powerstate == true){
     digitalWrite(ponpin,LOW);
     if(selpin == -1) return false;
     freq(frequency);
diff --git a/src/JJYReceiver.h b/src/JJYReceiver.h
index 920c1e9..1819b5f 100644
--- a/src/JJYReceiver.h
+++ b/src/JJYReceiver.h
@@ -57,7 +57,8 @@ class JJYReceiver {
     volatile enum JJYSTATE jjystate = JJY_INIT;
     volatile uint8_t rcvcnt = 0;
     volatile unsigned long fallingtime[2];
-    volatile int8_t datapin,ponpin = -1 ,selpin = -1;
+    volatile const int8_t datapin,ponpin = -1 ,selpin = -1;
+    volatile int8_t monitorpin = -1;
     volatile uint8_t frequency;
     // int agcpin;
     volatile uint8_t markercount = 0;
@@ -71,11 +72,10 @@ class JJYReceiver {
 
     volatile uint8_t sampleindex = 0;
     volatile uint8_t sampling [N];
-    volatile uint8_t CONST_PM [N] = {0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xF0,0x00,0x00,0x00};
-    volatile uint8_t CONST_H [N]  = {0xFF,0xFF,0xFF,0xFF,0xFF,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
-    volatile uint8_t CONST_L [N]  = {0xFF,0xFF,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
+    volatile const uint8_t CONST_PM [N] = {0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xF0,0x00,0x00,0x00};
+    volatile const uint8_t CONST_H [N]  = {0xFF,0xFF,0xFF,0xFF,0xFF,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
+    volatile const uint8_t CONST_L [N]  = {0xFF,0xFF,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
 
-    int8_t monitorpin = -1;
     volatile time_t localtime[3] = {-111,-222,-333};
     volatile time_t globaltime;
     struct tm timeinfo;
@@ -93,7 +93,7 @@ class JJYReceiver {
     void begin();
     void stop();
     // int agc(bool agc);
-    bool power(bool power);
+    bool power(bool powerstate);
     bool power();
     STATE status();
     uint8_t freq(uint8_t freq);