         // relative humidity with temperature correction (see hih_4030_fitting.m)
         hm = (0.0002f * temperature) + 0.0763f;         // x-coeffient fitting
         hb = (-0.0612f * temperature) - 24.4265f;       // b-term fitting
-        hih = hm * float(raw_hih) + hb;
+        hih = hm * float(raw_hih + 524) + hb;           // ADC ref (5.0 V)  this is scaling back the ADC reading
+        // hih = hm * float(raw_hih) + hb;              // ADC ref (2.56 V)
 
         // send humidity report
         report_humidity();

#define ADC_INTERNAL_MV 2.483f      // manual calibration (was 2.502f)
#define ADC_DEFAULT_V 0.004887f     // uncalibrated
#define ADC_DEFAULT_MV 4.887f       // uncalibrated

#define LED_PIN 13


        report_indicators();

        
        // send timestamp
        Serial.print("$TIME,");
        Serial.println(time_env, DEC);
