Radio would cut off.

First time having the boat out for the season and at the end of the first day the radio would cut off and a beeping noise would sound. Couldn't figure out what it was. Thought it was the radio, but after doing quick trouble shooting techniques, we were able to identify it wasn't the problem. Boat ends up not starting. had a battery brought out and once started we did the old alternater test. Well both original alternater and battery was dead. A G-Wizz, hopefully save you the same headache info.