diff --git a/lib/wsprd/fano.c b/lib/wsprd/fano.c
index bf2603a45..8fe1a649e 100644
--- a/lib/wsprd/fano.c
+++ b/lib/wsprd/fano.c
@@ -60,7 +60,7 @@ struct node {
  * and easier than trying to pack them more compactly.
  */
 int encode(
-	   unsigned char *symbols,	// Output buffer, 2*nbytes
+	   unsigned char *symbols,	// Output buffer, 2*nbytes*8
 	   unsigned char *data,		// Input buffer, nbytes
 	   unsigned int nbytes)		// Number of bytes in data
 {
@@ -69,7 +69,7 @@ int encode(
   int i;
 
   encstate = 0;
-  while(--nbytes != 0) {
+  while(nbytes-- != 0) {
     for(i=7;i>=0;i--) {
       encstate = (encstate << 1) | ((*data >> i) & 1);
       ENCODE(sym,encstate);
diff --git a/lib/wsprd/wsprsim_utils.c b/lib/wsprd/wsprsim_utils.c
index a42b1cfa7..49a118c03 100644
--- a/lib/wsprd/wsprsim_utils.c
+++ b/lib/wsprd/wsprsim_utils.c
@@ -296,10 +296,9 @@ int get_wspr_channel_symbols(char* rawmessage, char* hashtab, unsigned char* sym
     unpk_(check_data,hashtab,check_call_loc_pow,check_callsign);
 //    printf("Will decode as: %s\n",check_call_loc_pow);
     
-    unsigned int nbytes=11; // The message with tail is packed into 11 bytes.
-    unsigned int nencoded=162;
-    unsigned char channelbits[nencoded];
-    memset(channelbits,0,sizeof(char)*nencoded);
+    unsigned int nbytes=11; // The message with tail is packed into almost 11 bytes.
+    unsigned char channelbits[nbytes*8*2]; /* 162 rounded up */
+    memset(channelbits,0,sizeof channelbits);
     
     encode(channelbits,data,nbytes);