diff --git a/tests/test-hybridencode.py b/tests/test-hybridencode.py
--- a/tests/test-hybridencode.py
+++ b/tests/test-hybridencode.py
@@ -21,8 +21,8 @@ show("data/_")
 print "tilde is character-encoded"
 show("data/~")
 
-print "characters in ASCII code range 0..31"
-show('data/\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f'
+print "characters in ASCII code range 1..31"
+show('data/\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f'
           '\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f')
 
 print "characters in ASCII code range 126..255 (only partially tested)"
diff --git a/tests/test-hybridencode.py.out b/tests/test-hybridencode.py.out
--- a/tests/test-hybridencode.py.out
+++ b/tests/test-hybridencode.py.out
@@ -13,9 +13,9 @@ tilde is character-encoded
 A = 'data/~'
 B = 'data/~7e'
 
-characters in ASCII code range 0..31
-A = 'data/\x00\x01\x02\x03\x04\x05\x06\x07\x08\t\n\x0b\x0c\r\x0e\x0f\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f'
-B = 'data/~00~01~02~03~04~05~06~07~08~09~0a~0b~0c~0d~0e~0f~10~11~12~13~14~15~16~17~18~19~1a~1b~1c~1d~1e~1f'
+characters in ASCII code range 1..31
+A = 'data/\x01\x02\x03\x04\x05\x06\x07\x08\t\n\x0b\x0c\r\x0e\x0f\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f'
+B = 'data/~01~02~03~04~05~06~07~08~09~0a~0b~0c~0d~0e~0f~10~11~12~13~14~15~16~17~18~19~1a~1b~1c~1d~1e~1f'
 
 characters in ASCII code range 126..255 (only partially tested)
 A = 'data/~ \x7f \x80 \x81 \x82 \x83 .. \xfd \xfe \xff'