Thursday's Child came with some slightly older instruments including a Loran-C receiver. LORAN-C is a WWII era positioning system that uses radio beacons to help determine the position of the receiver. In recent years GPS has almost completely replaced LORAN-C and in Canada all of the radio beacons are being removed and the system has effectively come to an end.
I used to work at the Jericho Sailing Centre, one of the jobs I was tasked with was maintaining our rescue boat and most importantly the electronics aboard her. I quickly learned that the term "waterproof" was to a GPS what "unsinkable" was to the Titanic - a marketing gimmick and not a guarantee by any means. It was a miracle if we could get a GPS to last an entire season aboard Jericho Rescue - They would always get wet and stop working, we would return them under warranty and the manufacturer would inevitable try to avoid having to repair the units claiming they weren't designed for such exposed use. I often wondered what they were designed for but also knew trying to make a logical argument to an offshore technical support line was a complete waste of time. After running through a series of manufacturers we installed a Standard Horizon and to the shock of everyone it lasted well over a season and when it did eventually start to show signs of condensation under the glass screen it was repaired under warranty. Because of this I opted to replace the LORAN-C unit with a new fangled Standard Horizon CP300 chart plotter/GPS complete with external antenna and C-MAP charts. The Standard Horizon has a pretty standard list of features including NMEA connectivity which means it can talk to my wind instruments, VHF and any other marine electronics I fee like throwing in to the mix.
Installation was incredibly easy as I was mounting the GPS in the mobile instrument cluster where the LORAN-C unit used to be. I was able to use the LORAN-C antenna cable to pull the GPS antenna though the conduit and while I needed to make the hole slightly larger for the GPS I didn't need to move any of the other instruments around. I know I'm going to be much happier having a GPS and chartplotter aboard. There is nothing worse than pulling in to an anchorage having no idea what the topography looks like and desperately looking for a paper chart.