diff --git a/src/afsk.hh b/src/afsk.hh
index 186bcd2..92990cd 100644
--- a/src/afsk.hh
+++ b/src/afsk.hh
@@ -84,9 +84,13 @@ protected:
   /** Delay line index. */
   size_t _dl_idx;
 
+  /** Ring buffer of the last @c _corrLen symbols. */
   Buffer<int16_t> _symbols;
+  /** Insertion index. */
   size_t  _symbolIdx;
+  /** Sum of the current @c _corrLen symbols. */
   int32_t _symSum;
+  /** Sum of the last @c _corrLen symbols. */
   int32_t _lastSymSum;
 
   /** Last received bits. */
diff --git a/src/ax25.hh b/src/ax25.hh
index 59ce58d..f12dc7b 100644
--- a/src/ax25.hh
+++ b/src/ax25.hh
@@ -30,6 +30,7 @@ public:
   /** Processes the bit stream. */
   virtual void process(const Buffer<uint8_t> &buffer, bool allow_overwrite);
 
+  /** Unpacks a AX.25 encoded call (address). */
   static void unpackCall(const uint8_t *buffer, std::string &call, int &ssid, bool &addrExt);
 
 protected: