Servo und VirtualWire inkompatibel

#include <VirtualWire.h>

const int receive_pin = 11;

String Ergebnis ;

long int Ergebnis2;

volatile int ServoPos;

volatile int timeCount;

ISR( TIMER2_COMPA_vect)                // Interruptbehandlungsroutine

{

  timeCount++;

  if( timeCount == 2000 ){

    timeCount = 0;

    PORTB |= ( 1 << PORTB5 );

  }

  else if( timeCount == 150){

    PORTB &= ~( 1 << PORTB5 );

  }    

}

void setup() {

  Serial.begin(9600);

  Serial.println("setup");

  vw_set_rx_pin(receive_pin);

  vw_setup(2000);

  vw_rx_start();

  pinMode(4,OUTPUT);

  pinMode(5,OUTPUT);

  pinMode(2,OUTPUT);

  pinMode(13,OUTPUT);

  digitalWrite(4,LOW);

  digitalWrite(5,HIGH);

  analogWrite(2,0);

  //Servo

  TCCR2A |= (1<<WGM21);        // CTC-Mode

  TCCR2A &= ~(1<<WGM20);

  TCCR2B &= ~(1<<WGM22);      // CTC-Mode

   TCCR2B |= (1 << CS20);

   TCCR2B &= ~(1 << CS22);

   TCCR2B &= ~(1<< CS21);

  TIMSK2  |= (1<<OCIE2A);      // Timer-Compare Interrupt an

  OCR2A = 159;                         // Neutralposition ((2500-2312)*0.008ms)=1,5ms)

  sei();                                // Interrupts global an

  timeCount = 0;

}

void loop() {

  int i;

  uint8_t buf[VW_MAX_MESSAGE_LEN];

  uint8_t buflen = VW_MAX_MESSAGE_LEN;

  vw_get_message(buf,&buflen); 

  Ergebnis=String(buf[0]-48)+String(buf[1]-48)+String(buf[2]-48)+String(buf[3]-48);

  Ergebnis2 = Ergebnis.toInt();

  Serial.println(Ergebnis2);

 Ergebnis2 = map(Ergebnis2,0,1024,100,200);

 Serial.println(Ergebnis2);

 analogWrite(2,Ergebnis2);

  vw_wait_rx();

}