Abstract: A high voltage power line phase-angle and current measuring instrument suitable for mounting on the end of a power line hot stick is disclosed. The instrument is capacitively and inductively coupled to a single power line conductor whose phase angle and/or current are to be measured. The capacitive and inductive coupling produce voltage and current signals that are processed in voltage and current phase channels. The voltage and current phase channels filter and square the signals in a phase coherent manner, i.e., the phase relationship between the voltage and current signals is maintained as the signals are filtered and squared. The resulting voltage and current square-wave signals are applied to a signal processor.