diff --git a/protocol/esta/analog/receiver.h b/protocol/esta/analog/receiver.h
index 24b0db0..b7ba3c7 100644
--- a/protocol/esta/analog/receiver.h
+++ b/protocol/esta/analog/receiver.h
@@ -45,16 +45,15 @@ struct Receiver
   /**
    * @brief Convert millivolts to an 8-bit level.
    * @param mV
-   * @return
+   * @return \cite ANALOG 5.4 Scale: control is intended to be linear
    */
   uint8_t level(const int16_t mV) const
   {
     if (mV <= zero)
       return 0;
-    else if ( mV >= full)
+    if ( mV >= full)
       return UINT8_MAX;
-    else
-      return (mV - zero) / (full - zero);
+    return UINT8_MAX * ((mV - zero) / (full - zero));
   }
 
   /**