Navigation General · Light Characteristics
An ISOPHASE light (Iso) has which characteristic?
- AEqual periods of light and darkness✓ Correct
- BThree flashes followed by a long eclipse
- CRapid flashes of less than 0.5-second duration
- DA single long flash repeated every 10 seconds
Explanation
An Isophase (Iso) light has equal durations of light and darkness — the light-on period exactly equals the light-off period within each cycle.
Authority: 33 CFR 62 (U.S. ATON System)
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