Instruments
One of the first projects, once we got Hopscotch home, was to organize the electronics. The boat originally was outfitted with Signet instruments, both wind speed and direction, and depth/boatspeed. The wind instrument had already been replaced by a Raymarine unit. The depth/boatspeed supposedly worked but the readout had lost its display. I contacted Signet and learned that the transducer ran at 160 KC instead of the 200 KC which is almost universal. They are no longer available. I could have gotten the display repaired for $350 but it would become junk if something were to happen to the transducer. Accordingly, the Signet would be removed.
The boat had new electronics installed in 2006, including a Raymarine multi-function display and 4 KW Radar, also Raymarine. It was obvious that standardizing on Raymarine would make sense. I immediately went out and bought a Raymarine autopilot and depth sounder. The depthsounder came w/o a transducer. And, I had forgotten about the balsa core in the hull. I could bore a hole in the hull and cut back the balsa in the area around the transducer but that risked getting moisture into the balsa and would be a last resort. The transducer wouldn't work transmitting thru a balsa cored hull. It needed a clean area w/o balsa.
I had installed a $100 cheapy depthsounder in my last boat and reused an old transducer, so I already owned a brand new 200 KC through-the-hull transducer. Using it instead of buying one from Raymarine for $350 it made sense if the transducer were compatible and if I could find a place where I could install it.
The first test would be to connect the readout and transducer and turn the unit on. I put the transducer in a big plastic bag with about a gallon of water and dropped it over the side to see what would happen. Initially it showed nothing until I discovered that it took a few moments to warm up before it read the right depth. The next step would be to place it against the hull up forward under the vee berth where there was a small area with balsa. And it worked! I had to clean an area for the transducer and it’s plastic tank down to the gell coat and flat enough to glue down the tank. Once this was done and the tank filled with some mineral oil, it was a simple matter to run the wiring and mount the instrument.
Next project: the autopilot.
The autopilot installation was very straight forward, once I was able to locate the components: the readout, the fluxgate compass, the computer and the steering motor and fishing the various cables. The fluxgate compass is a can about the size of a tennis ball. It needs to be near the centerline of the boat and away from any ferrous metal such as the engine and hopefully within reach of the supplied cable. After a couple of trial runs, the can was mounted and the cable run. Thefinal components, the readout and the steering motor needed to be mounted where they could be accessed by the helmsman. These decisions were simple because there weren't any real options.
The cable for the steering motor needed to be fished down inside the binnacle and connected to the autopilot computer. This looked to be a hard task, as there was no room inside the binnacle for access and the cable had to be routed away from the steering cables. A friend said not to worry, just put a weight on a piece of string and drop it down the binnacle. There is a 1" hole in the cockpit sole at the front of the binnacle that was used for the compass light. Dropping a small weight on a 2' string down through that hole looked to be a challenge that I'd do tomorrow.
The next day I drilled two holes in the binnacle tube at aconvenient height and tied a small steel nut on a piece of string and dropped it down the hole and tied it off just about at the hole. I went down under the cockpit and fished around through the hole with a finger magnet to see what would happen and "click" the nut attached to the magnet. From there, it was a simple job to pull the nut and string down through the hole and fish two wires back up from below to be used for the autopilot and GPS that was left over from my old boat. The whole wiring job took maybe ten minutes.
Once all the rest of the components were mounted the cables run, the autopilot needed to be calibrated which is what allowed the readout to show the heading of the boat.
SeaTalk connections
One of the advantages of standardizing on Raymarine was that it was simple to network the various electronic instruments. In addition to the Raymarine components, I had installed the GPS from my old boat and a Standard Horizon VHF/DSC/AIS and RAM Mic. The VHF had to be connected to the GPS for the DSC to work. And, the AIS had to be connected to the multi-function display. The GPS cable had 12V input to the GPS and there were GPS output wires to the VHF. I secured the cable from the GPS to the overhead and bundled it to the cable run that was already there going to the engine controls, the autopilot etc. At the end of this cable, I mounted an electrical handybox. From this box, I ran a length of (AWG8) conductor cable I’d removed along with the dead LORAN. I continued this cable to the VHF with a handybox at the autopilot computer and at the VHF. Inside the handyboxes I mounted terminal strips to connect the network. This allowed for all the interconnections between the different components in a neat businesslike manor that would be simple to maintain in the future.
I’m still learning how to use all these things, but now there is a readout on the multi-function display that shows boat heading, windspeed, depth, AIS alarm status as well as the autopilot. There’s even a capability to disconnect the autopilot by punching a button on the multi-function display.
This has been a description of how I did it, not an instruction of how to do it. With the data cable run with access boxes where appropriate and terminal strips inside the boxes, it’s simple to follow the wiring diagrams from the equipment manuals and connect the reds to the reds and the blues to the blues etc., using a small screwdriver instead of twisting pairs and insulating tape. The SeaTalk cables have 3-pin plugs that connect to matching 3-pin receptors in the Raymarine instruments so the wiring is simple enough to connect.