Path for radar cable

[Mike Loft]

I'm looking at the alternatives on where to install the radome, and the chartplotter/radar display, on an E32-200. On this boat it looks like the steering pedestal is the only feasible and useful place for the display. So cable has to get there, either from the stern, or up on the mast. Running cable to that location from the mast raises issues of messing up the headliner and possibly having to cut and splice the cable to cover that much distance. A stern pole mount is easier in that respect, but may be considerably more expensive-- just because the pole etc is pricey.

Although I'm leaning toward a stern pole mount, I'm wondering if running the cable inside the headliner is actually the only way to route the cable when the radome is on the mast. I could do a mast mount and avoid messing with the headliner if the radar cable were routed under the cabin sole, aft to a point under the pedestal. This would involve drilling sizeable holes through the fiberglass substructure of the boat, from near the mast base, going aft. It doesn't seem like a foregone conclusion that running cable through the bilge, and drilling these holes in the glass longitudinally from the mast base to a point under the pedestal, is O.K. Do any of you have any opinions about going with a mast mount and routing the cable this way? Thanks for your help.

 

[ref_123]

Other alternatives

Hi Mike,

I have the radar on a swinging arm near the companionway, so I can watch it from inside the cabin or from the cockpit. Works reasonably well.

The radome is mounted on the mast. The cable seems to be too thick to put it under the headliner. So my cable goes from the hole near the mast boot to the port side locker to the junction box. From there you can easly route it under the sole or behind the seats (in my case). I can barely see that piece of cable between the mast and the setee, about 3 inches. The junction box also makes disconnecting to pull the mast out pretty easy too.


I am far from believing this is the best set up in the world, but it works. As for the pole, it probably works better, particularly those with the leveling capability, but as you pointed out, it's more expensive.

Also, being a former air defence officer, I am a bit apprehensive about high-power transmitter right above the helmsman head... and the radiation diagram for most units hints at potentially sweeping the foredeck... but it's my personal paranoya and nobody needs to share it .

Regards,
Stan
E32-3 Fire Eater

 

[rwthomas1]

I redid the radar in my E38 last year. The radome is on the mast, just replaced the old with new. KISS. I was able to run the cable in the headliner. It was a major PITA but it works. I purchased two cables, one for the boat and one for the mast. The radar/chartplotter is at the helm, the cable runs down the stainless pedestal leg, back behind the quarterberth and into the headliner there, coming forward to transition up the the main salon headliner and again forward to the mast. I know the E38 is substantially different but you get the idea. I used a Molex type 16pin connector at the mast junction to allow easy removal of the mast. Hope this helps. RT

 

[ChrisS]

Mike--

I am going through the same process right now, and the consensus seems to be that to correctly install the raydome on the mast with a deck-stepped boat, the mast has to be pulled, which I don't want to do unless I take on a few other projects. So I am going the pole route--the Garhauer one is quite resonably priced, and will also give me a place to stick a solar panel. The display will go by the helm so I can see and adjust it while manuvering.

Good luck in figuring out your setup. Lots of variables here!

 

[Carlos]

Raydome on mast

I recently installed a radar on the mast of my 30+. If I were to do it again I would probably not. It was a pain getting a hole large enough in the mast boot to pass the cable through. I caution you not to splice the cable. The cable has a coax tucked inside that is difficult to match, let alone splice. Besides that, the conductors have to be sized for the length of cable. Pay the big bucks and buy the longer cable if needed.

 

[Brian K]

Hey Mike, I also have a 32-200 with radar. The display is located on a swinging arm near the companionway, like Stan described. He is correct this location you can watch it from inside the cabin or from the cockpit. The thing I don't like about this location is that it is easy to hit on your way down the companionway stairs. My radome is located on a pole on the stern. As for running the wires, it's funny that this subject comes up. The wires from the radar tower enter the boat through the plastic vent on the transom. I don't really use the radar much but want to become better at reading it, so I'll try to use it more this year. If you want more specific info on the 32-200 installation, let me know. You can email me directly at brian.king@us.ngrid.com

 

[rwthomas1]

I recently installed a radar on the mast of my 30+. If I were to do it again I would probably not. It was a pain getting a hole large enough in the mast boot to pass the cable through. I caution you not to splice the cable. The cable has a coax tucked inside that is difficult to match, let alone splice. Besides that, the conductors have to be sized for the length of cable. Pay the big bucks and buy the longer cable if needed.

I'm sorry but I would have to disagree with you. The cable length is not the issue, you have to have a splice with a connector if you ever intend on removing the mast. We have this thing called "winter" here and many people pull the mast each season..... Splicing to a plug or "molex" type connector is tedious but relatively simple. Or you can have your electronics installer do it for you. I purchased the correct male and female plug ends and the respective pins along with the correct crimping tool and did it myself. Splicing and crimping ends on coax is just as easy as any other wire. You just have to pay attention. Granted, if you are ham-fisted and have never done something like this before then you probably shouldn't try it. Then again, you would likely also have trouble installing the radome, pulling the wires, etc, etc. If you can are the type that does all the maintenance on your boat, and does it correctly, you can handle this.

RT

 

[Carlos]

Running cable to that location from the mast raises issues of messing up the headliner and possibly having to cut and splice the cable to cover that much distance.

Mike;

I may of misunderstood you, when you wrote that distance was an issue and that you might have to splice the cable. I thought you meant you would have to lengthen the cable by splicing in additional length. Splicing usually means cutting and adding cable or bifurcating with additional cable. We don't splice in connectors we terminate cables with connectors.

No matter how you lengthen the cable you must consider signal loss. If you look at Furuno cable specifications, you'll see that for 30m cable 24VDC is required vs 12VDC for 20m or shorter. There is a reason for this.

Coax cables come in many different sizes and impedances. Also, the wrong connector or improperly installed connector can cause signal loss or EMI issues. There is a lot of engineering that went into that cable that comes with your radar unit. Altering it could cause many problems.

I'm just saying, check with the manufacturer before lengthening the cable or even cutting and terminating it with a connector. The manufacturer may have the solution for you. They may even custom make a cable with a connector at the mast step if that is what you want.

 

[Brisdon]

I have mine on a back stay gimble. A little less annoying than the lolly pop sticking up on the corner of the transom, but still sort of an expensive piece of equipment. Easy to wire though, no mast involvement.

 

[rwthomas1]

Mike;

I may of misunderstood you, when you wrote that distance was an issue and that you might have to splice the cable. I thought you meant you would have to lengthen the cable by splicing in additional length. Splicing usually means cutting and adding cable or bifurcating with additional cable. We don't splice in connectors we terminate cables with connectors.

No matter how you lengthen the cable you must consider signal loss. If you look at Furuno cable specifications, you'll see that for 30m cable 24VDC is required vs 12VDC for 20m or shorter. There is a reason for this.

Coax cables come in many different sizes and impedances. Also, the wrong connector or improperly installed connector can cause signal loss or EMI issues. There is a lot of engineering that went into that cable that comes with your radar unit. Altering it could cause many problems.

I'm just saying, check with the manufacturer before lengthening the cable or even cutting and terminating it with a connector. The manufacturer may have the solution for you. They may even custom make a cable with a connector at the mast step if that is what you want.

Splicing, terminating, or whatever term you choose is obviously necessary if you ever want to remove the mast from a boat with a radome on the mast. I did my "termination" with the advice of my electronics supplier. I used a connector that met their specs and the entire installation was checked by them when they tuned it and the AP. This isn't a WM, box store, etc. They are a respected company that handles service and installation, maintains an active repair shop full of tools and several ex-military radar techs. The installation passed Furuno, the shop specs and the warranty is intact. FWIW, I "terminated" new connector ends on two 10 meter cables, after cutting the excess off, well within the specs. I'm not advocating that someone just randomly crimp bullet connectors onto a cut cable, willy-nilly. Do the research, talk to the pros, learn what not to do, and its completely achievable.

RT

RT

 

[Mike Loft]

Carlos: I probably created some confusion myself by not knowing what happens over the entire run of cable from mast, to a coax fitting somewhere, and then onward from there. Your interpretation of what I said about distance and the possibility of splicing was correct, and I think your comment about it is correct-- that "splicing" a radar cable isn't something to be taken lightly. On the other hand, the comment from rwThomas that there necessarily has to be a "splice" of some kind, somewhere, so that the mast can be removed when necessary, also has to be true. So what I take from this is that "lengthening" the radar cable in connection with a mast mount can certainly be (and to facilitate mast removal, must be) done, but requires some special attention and the right materials. Between that and having to go out through the lower part of the mast and then through an aging headliner, I'm leaning toward a stern pole mount-- which has issues of its own.