diff --git a/README.md b/README.md
index eb4d13b..a5affbf 100644
--- a/README.md
+++ b/README.md
@@ -125,6 +125,10 @@ buttons to find them.
 * AIRCOPY RX'ing radio now requests packet resends from TX'ing radio if RX'ed packet is lost/corrupted
 * ..
 
+# Symbol information
+
+<img src="/images/symbols.png" />
+
 # Compiler
 
 arm-none-eabi GCC version 10.3.1 is recommended, which is the current version on Ubuntu 22.04.03 LTS.
diff --git a/images/symbols.png b/images/symbols.png
new file mode 100644
index 0000000..411e50f
Binary files /dev/null and b/images/symbols.png differ
diff --git a/radio.h b/radio.h
index 7e4cd18..ba751cc 100644
--- a/radio.h
+++ b/radio.h
@@ -113,7 +113,7 @@ typedef struct vfo_info_t
 
 	uint8_t        compand;
 
-	uint8_t        frequency_channel; // channel number if a channel is set to this vfo's frequency
+	uint8_t        frequency_channel; // channel number if the VFO's frequency is found stored in a channel
 
 	char           name[16];
 } vfo_info_t;