EPIRB Class B is described as

EPIRB Class B is described as

• A. 121.5/243 MHz Float-free, automatically activating
• B. 121.5/243 MHz Manually activated version
• C. VHF Channel 70 Manually activated
• D. 406 MHz beacon

Answer: (B)

The key idea is that EPIRBs come in variants distinguished by both how they activate and what frequencies they use. Class B refers to the manually activated type that transmits on the traditional distress/homing frequencies of 121.5 and 243 MHz. This means you must physically activate the beacon in distress, and its signals are designed primarily for locating you with ground or air SAR teams using the 121.5/243 MHz beacons. It’s not the float-free automatic type (which would activate automatically when in water) and it’s not the 406 MHz beacon type, which is a separate category with newer satellite-assisted signaling. So the description that best matches Class B is the manually activated version operating on 121.5/243 MHz.

The key idea is that EPIRBs come in variants distinguished by both how they activate and what frequencies they use. Class B refers to the manually activated type that transmits on the traditional distress/homing frequencies of 121.5 and 243 MHz. This means you must physically activate the beacon in distress, and its signals are designed primarily for locating you with ground or air SAR teams using the 121.5/243 MHz beacons. It’s not the float-free automatic type (which would activate automatically when in water) and it’s not the 406 MHz beacon type, which is a separate category with newer satellite-assisted signaling. So the description that best matches Class B is the manually activated version operating on 121.5/243 MHz.