two antennas

[dvx216]

When I know who high I am I usually can't remember where I'm at.

Clinton signed the order for civilian use GPS in the early 90's if memory serves, and then around 2000, civilians got the high accuracy signal. There was really no 'throw the switch' moment where the world stopped using Loran C and went to GPS. Loran went side by side with GPS well into the 2000's.
2010 The US and Canada shut down thier Loran systems. Yes, by the time that the OP's boat was setup, GPS was the standard.

It was either 1994 or 95, I worked in a lab and we were tasked to do some high/low altitude testing on oxygen concentrators in Death Valley and Mammoth Lakes CA, so we purchased a hand held Garmin unit. ~=$1600! and it only told you where you were and how high you were.

In checking over some of the spec sheets for boats I have looked as, Sea Ray was still offering Loran systems as an option at least as late as 1996.

 

[northshore]

When I know who high I am I usually can't remember where I'm at.

A little twist on Heisenberg? :smt043

 

[Jandcinok]

We ran into this issue last year. They looked just alike but, one was VHF, one was am/fm. Ours were Shakespeares, they look just
alike but there is a difference.

 

[boatn]

There's probably a manufacturer's name - Shakespeare, Digital Antenna, etc - and a model number on the antenna. Go to the manufacturer's website and see what that model antenna is for.