What is the maximum power output authorized for VHF radios?

The maximum power output authorized for VHF radios in maritime use is 25 watts. This limit is established to ensure efficient communication while minimizing interference with other channels. VHF radios operate on line-of-sight propagation, meaning that higher power levels generally offer diminishing returns in range due to the nature of radio wave transmission.

A 25-watt output is sufficient under normal operating conditions to maintain clear communication over distances commonly encountered in maritime environments. Exceeding this power could result in excessive interference with other vessels and potentially disrupt distress communications, which is why regulation caps the output at this level. Thus, the designation of 25 watts aligns with best practices for safety and regulatory compliance in maritime operations.