The term 'SORT OF SIGNAL' can be broken down into two crossword solutions: BUZZ (4 letters) and BEEP (4 letters). Both BUZZ and BEEP are types of signals that are used to indicate a warning or alert. BUZZ is a low-pitched sound that is often used to indicate an alarm or warning, while BEEP is a higher-pitched sound that is typically used to indicate a warning or alert. Both BUZZ and BEEP are commonly used in electronic devices such as computers, phones, and other electronic equipment.