An array of light-emitting diodes (1-15) in a circular arrangement are illuminated to indicate the discrete magnitude of rate-of-turn and the direction of turn. The number of diodes (1-15) illuminated is indicative of the discrete magnitude of turn and the clockwise or counterclockwise direction of illumination of the diodes is indicative of the turn direction. The current and preceding samples of the grey coded step data compass heading output are compared (12) to detect incremental changes in heading. The incremental changes are counted over a predetermined time interval to provide a count signal (14) representative of turn rate. Logic (14) responsive to the count signal illuminates the appropriate number of light-emitting diodes (1-15). Further logic (35, 36) responsive to the grey code heading data sequence provides a direction of turn signal to illuminate the light-emitting diodes (1-15) in a clockwise or counterclockwise direction as appropriate.