a signal converter for use in a recording or displaying device which can be used to change the size of characters to be recorded or displayed . by using instruction signals or enlargement codes , a part of a character field and hence a corresponding part of a character may be enlarged , and then the enlarged upper and lower halves are combined to form an enlarged character for recording or display . any number of characters in a row of characters may be changed in size by using the signal converter , and specified portions of different characters may be enlarged and then combined .