I have a SH 300i chartplotter with all the standard alarms, etc.
The audible alarm is the same beep as the keyboard input beeps so is
not loud. It is not adjustable and there is no remote alarm jacks. So,
with it mounted at the helm and you're at anchor and taking a nap below,
how do you hear the anchor drag alarm?

I thought of a baby monitor but most, if not all, require ac at the
xmitter which would be another pain.

So, any suggestions?

I'm trying to get a schematic for the alarm circuit from SH but I
doubt they will come through.
Gordon