that 16 yr old sailor who cares, page-114

Yep, 'guard rings' are a standard software option on radar units. You can select varying rings from say 2 nm to 16nm. If any target get closer then the distance setting, an alarm will go off. Jessica said she was not woken be the alarm.

They have since linked the alarm to a loud horn, so she will wake up in future.

This is all standard practice for single handed sailors - radars; guard rings; short sleeps.


Cheers, Skip