Installing AIS/VHF antenna

quinsky

Well-known member
Joined
Jul 25, 2017
Messages
161
Fluid Motion Model
R-21 EC
Hull Identification Number
FMLC2813H
Vessel Name
Compass Rose
MMSI Number
338302374
I'm installing AIS on my C28 and want to mount the AIS/VHF antenna on the port side opposite the existing VHF antenna. I prefer to secure the antenna mount with thru-bolts but I need to access the the roof from inside. Does anyone know how to remove the wood valence that supports the side curtain track in the cabin? I removed the only two larger/longer screws that were located on the aft end. I removed one of the smaller screws used to mount the curtain slide but it seems too small to support the valence. I don't see any other larger screws. I figured I'd ask before I removed all the screws in the slide.
 
Quinsky: take lots of photos when you do this project as I'd love to follow along!
 
Cutwater28 GG, I will. I decided to go with the Vesper XB6000 which has an internal GPS antenna. I'm running out of places to put antennas 😀 Vesper advises mounting the unit at least 2ft away from the compass. That pretty much eliminated the electronics locker in the head. My first thought was to mount it up in the Vberth to the side and behind the mirror. It would still be mostly visible and the antenna wouldn't be obstructed be deck gear. However it is a long run for the VHF antenna cable, about 35 ft. Certainly I can get a 35 ft cable but the antenna I purchased has a 21ft cable included. My next option is to mount the unit down in the cave on the bulkhead next to the breaker panel. The problem there is GPS reception If I can run the VHF antenna without much problem I may go ahead and mount a GPS antenna. I will will keep you posted.
 
Thankyou!

Is there anyway you can take the GPS feed from the existing GPS puck on the NMEA network?

With all these devices needing GPS signals some boats end up with a GPS puck farm on the roof!
 
I did note on the Vesper website that the external GPS puck can be used for the entire NMEA network (so the other way around) if the existing puck has good refresh rates and the vesper can accept the GPS data from the NMEA network rather than plugged directly this might minimize hole drilling. Probably worth calling Vesper marine?

The fast 5Hz GPS update rate results in higher resolution and smoother tracks on your plotter or MFD, even during high speed maneuvers. It can be used as a source of GPS data for the entire NMEA 2000 network

https://www2.vespermarine.com/xb6000-ais-transponder#features
 
Cutwater28GG":35yocte4 said:
Thankyou!

Is there anyway you can take the GPS feed from the existing GPS puck on the NMEA network?

With all these devices needing GPS signals some boats end up with a GPS puck farm on the roof!
It is my understanding that a Class A AIS, one that transmits, requires it's own separate independent GPS signal. I don't believe you can use existing GPS info that is on the NMEA network.
 
Cutwater28GG":2e3xphrn said:
I did note on the Vesper website that the external GPS puck can be used for the entire NMEA network (so the other way around) if the existing puck has good refresh rates and the vesper can accept the GPS data from the NMEA network rather than plugged directly this might minimize hole drilling. Probably worth calling Vesper marine?

The fast 5Hz GPS update rate results in higher resolution and smoother tracks on your plotter or MFD, even during high speed maneuvers. It can be used as a source of GPS data for the entire NMEA 2000 network

https://www2.vespermarine.com/xb6000-ais-transponder#features

Vesper is stating that the high performance GPS receiver in their AIS transceiver can feed the NMEA 2000 network. It may have a faster update rate than the existing GPS, older GPS are 1 Hz. As previously stated an AIS transceiver is required to have its own GPS.

Howard
 
Its my understanding that the AIS cannot share GPS with a MFD. That is why I purchased the Vesper XB6000 with an internal GPS antenna. Initially I dreaded mounting another antenna and I was concerned that the boat would look like a NASA tracking station. Since the boat is torn apart I might as well run another cable for the GPS antenna included with the XB6000. I'll mount it on the roof rack rail forward of the AIS antenna. This will only require one more hole for the cable. When done there will be a total of seven antennas plus radar! (2 GPS, TV, WIFI booster, AIS,VHF, and Sirius/XM).
I posted pictures of my progress in my photo album. Knotifying was right, the screws to the valance are recessed under the curtain track. (Thanks). Once the valance was removed I removed the screws holding the headliner. I could not pull it down enough to expose the side of the roof so I had to remove the forward port hatch trim. That provided relatively good exposure to the side. It was a pinch getting my hand in there to apply the nuts and washers. I stood on the co pilot seat and was able to stand up through the hatch and hold a screwdriver on the outside while tightening with a wrench on the inside. I was so proud of myself until I realized I had the mount base upside down. That means the release lever is inboard. It works fine and I can live with that- lesson learned! I try to think these things thru but sometimes my ADD gets in the way :roll:. Next I will run the cables over the headliner on the starboard side down to the aft end of the cave. The wood side panel next to the settee is easy to remove. I'll provide another update when I get it all done. My only concern is that I didn't draw any blood. Thats a bad omen but there's still time.
 
Good work!

Did you seal the bolt holes in the roof with 5200 or something similar?
 
Yes 5200. The base plate had a rubber gasket so I just squirted 5200 in the screw holes. Be sure to put a drop cloth over the co pilot seat. I dripped 5200 on the seat when I pushed the screws through. Fortunately it was on the vinyl and not the cloth. Again with the ADD!
 
nice
was it significantly painful to get the liner back in the right place after having removed it from the hatch and behind the wood valence?

Im always concerned that once I start such a project I basically ruin my boat because it doesnt go back just as it was!
 
I'll let you know. Still waiting for GPS antenna.
 
I finally received the AIS and got it all installed in the cave. I added some photos to my album. Putting everything back together was not too bad. Just make sure everything is back in the original position so the holes line up. I was having problems with the valance until I realized it was half an inch too far forward. A couple of screws in the coach roof panel have stripped out so I had to use longer screws. (It screws into wood). Be sure that all the wires are up over the headliner before reattaching the center panel so they don't get pinched. When removing that panel I used bungee cords to support it so it didn't hang on the light fixture wires. The hatch trim went back in easily. I ended up using the surface mount GPS antenna that came with the AIS and mounted it forward on the roof. Both cables are run over the starboard headliner and down the behind the side panel to the cave. I had to disconnect the seat support rod to fold the seat forward enough to remove the panel. Just remove the black cap on one end and pop it off. I discovered a 3 inch hole in the side panel in the cave which was covered with rabbit fur from the factory. I ran the cables through it and installed a cable hole trim (??) from a computer desk.

The current issue is adding a tee to the NMEA2000 backbone. Mine consists on all black tees that are mounted against the helm bulkhead in the electrical locker. I ordered one from an Ebay site that showed the same tee. The one I received was grey and mounts at a 45 degree angle relative to the black ones. Unfortunately it angles in toward the bulkhead on the left end. I don't have room to mount it on the right end. I returned it and ordered one from Garmin. Again the website showed a black one. Surprise!, they sent me a grey one! I guess they don't make the black ones anymore. I will have to unmount the backbone to attach it I guess.

So this weekend I decided to flush the water tanks. I hooked up a hose and went into the cave to see how the new tank would fill. There was a pray of water coming from up around the deck fitting. Its a good thing I had all the panels removed or I wouldn't have noticed. There was a small crack in the hose just below the fitting. The fitting was easy to remove using a screwdriver to carefully pry it off the deck. New hose is on the way.
 
Just looking to learn here. If you had gone with a Garmin AIS unit, wouldn't it have been much simpler, and fitted behind the dash next to the chartplotter and VHF radio? Or is that only true for the "receive only" units? I have a C28 and have wondered about this upgrade also. Roger, Kingston, Ontario
 
The Vesper is about $300 cheaper than Garmin. I did not mount it behind the helm because it was too close to the compass. The Vesper instructions state the when the GPS is running it can affect the compass if within two feet. I don't know if that is true of other AIS units. This unit has indicator lights that I can see where its mounted. Again, mounting the external GPS antenna was an afterthought and I had already purchased the Vesper. Thats my story and I sticking with it!
 
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