diff --git a/src/ax25.c b/src/ax25.c
index 1a54082..8e0f8b1 100644
--- a/src/ax25.c
+++ b/src/ax25.c
@@ -6,7 +6,6 @@
 #include <patty/ax25.h>
 
 enum addr_state {
-    ADDR_NONE,
     ADDR_CALLSIGN,
     ADDR_SSID
 };
@@ -21,7 +20,7 @@ int patty_ax25_pton(const char *callsign,
 
     int ssid = 0;
 
-    enum addr_state state = ADDR_NONE;
+    enum addr_state state = ADDR_CALLSIGN;
 
     if (len == 0) {
         goto error_invalid_callsign;
@@ -33,16 +32,6 @@ int patty_ax25_pton(const char *callsign,
         uint8_t c = callsign[i];
 
         switch (state) {
-            case ADDR_NONE:
-                if ((c >= '0' && c <= '9') || (c >= 'A' && c <= 'Z')) {
-                    state = ADDR_CALLSIGN;
-                    addr->callsign[o++] = (c & 0x7f) << 1;
-                } else {
-                    goto error_invalid_callsign;
-                }
-
-                break;
-
             case ADDR_CALLSIGN:
                 if (o > PATTY_AX25_CALLSIGN_LEN) {
                     goto error_invalid_callsign;
@@ -59,7 +48,7 @@ int patty_ax25_pton(const char *callsign,
                 break;
 
             case ADDR_SSID:
-                if (digits >= 2) {
+                if (digits == 2) {
                     goto error_invalid_callsign;
                 }