As character names:

U+01DE LATIN CAPITAL LETTER A WITH DIAERESIS AND MACRON character (Ǟ)

As raw characters:

Ǟ

As a string of HTML entities:

Ǟ

Decoder output:

Byte number 1 is decimal 199, hex 0xC7, octal \307, binary 11000111
This is the first byte of a 2 byte sequence.

Byte number 2 is decimal 158, hex 0x9E, octal \236, binary 10011110
This is continuation byte 1, expecting 0 more.

U+01DE	LATIN CAPITAL LETTER A WITH DIAERESIS AND MACRON
	: 00C4 0304