     if (top < sizeof stack)
       stack[top++] = value;
     value = 0;
-  } else if (('a' <= c && c <='z') || (c =='+')) {
+  } else if ('a' <= c && c <='z') {
     Serial.print("> ");
     for (byte i = 0; i < top; ++i) {
       Serial.print((int) stack[i]);

//                                                                         0, 433, 864, 912 MHz
         if (value) {
          Serial.print(config.frequency);
          config.frequency = config.frequency + value;       // 96 - 3960 is the range of values supported by the RFM12B
          if (config.frequency > 3960) config.frequency = 96;
          Serial.print("->");
          Serial.print(config.frequency);
          rf12_control(0xA000 + config.frequency); 
          Serial.println();
          saveConfig();
         }
         Serial.println(config.frequency);
        break;
      case 'g': // set network group
        config.group = value;

  if (config.nodeId & COLLECT)
    addCh(config.msg, '*');
  
  strcat(config.msg, " g");
  addInt(config.msg, config.group);
  
  strcat(config.msg, " @");
  static word bands[4] = { 0, 430, 860, 900 }; // 315, 433, 864, 915 Mhz    // 96 - 3960 is the range of values supported by the RFM12B
  band = config.nodeId >> 6;
                                                   Serial.println(config.frequency);
  long wk = config.frequency;                
                                                   Serial.println(wk);
  wk = wk * (band * 25);
                                                   Serial.println(wk);
  long characteristic = wk/10000;
                                                   Serial.println(characteristic);

  addInt(config.msg, characteristic + bands[band]);
  Serial.println(wk - (characteristic * 10000));
  byte pos = strlen(config.msg);
  addInt(config.msg, ((10000 + (wk - (characteristic * 10000)))));;
  config.msg[pos] = '.';
  strcat(config.msg, " MHz");
  Serial.println(strlen(config.msg));
  config.crc = ~0;
  for (byte i = 0; i < sizeof config - 2; ++i)
    config.crc = _crc16_update(config.crc, ((byte*) &config)[i]);
