Radar Questions from a Radar Newb

Fever

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#1
Hi All-

Going to mount a Garmin 18XHD to the hardtop on my 208 Adventure. Some of the Garmin Install specs have me asking questions, so I am looking for other people's input, in case your experience can help address my concerns.

Since I see most radomes mounted directly to the hardtop, I'm assuming they've worked just fine. Potentially, the Garmin instructions are for "Ideal" mounting, and these concerns I've listed below haven't caused issues, or the issues are very minor. Let me know! Thanks in advance! 8)


Mounting so that radar beam is above personnel head height. Doing some math, it looks like people in the stern of the boat could be in the line of the radar beam while standing. I was considering 12 degree up and down from horizontal center-line according to Garmin. Forward of the radar I don't consider an issue unless I have the radar turned on and someone walking on the bow.

Mount considering potential blocking radar beam by other equipment My VHF antenna extends about six feet above the hard top. Fishing rods in the rocket launchers are in the radar path aft of the radome. The GPS antenna is Garmin surface mount, only 2" max high. I think it's below the radar sweep.

The device should be mounted at least 1 m (40 in.) from any transmitting equipment and/or cables carrying radio signals such as VHF radios, cables, and antennas. On my 208, the Radome mounted dead center on the hard top will end up just under 3' from the VHF Antenna and the Radar Cables will be very close to each other in the cable raceway. (I'll have to provide shielding for the cables, but will the VHF antenna be an issue?) Also, the VHF radio is mounted in the hardtop radio box, only 1-2 ft from the radome.

I think that's it! Will be nice to get radar and be able to travel in the fog with a little more security.

Mike
 

ocnslr

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#2
Fever said:
Will be nice to get radar and be able to travel in the fog with a little more security.
Mike
None of those should be an issue on your installation.

As to your last comment, radar is to help get you home when the fog surprises you while out. Don't let it lull you into going out in the fog. Far too many "ejeets" out there running at high speed with their radar on, thinking that means "shields up, Scotty".

Brian
Master, Oceans, 1600-tons
Chief Mate, Oceans, Unlimited
Commander, US Navy (Ret).
 

Fever

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#3
radar is to help get you home when the fog surprises you while out. Don't let it lull you into going out in the fog.
Most definitely. The reason I'm getting radar is from being surprised by a fog bank 20 miles from home in the San Juan Islands a few times too many. GPS is good enough to crawl home, but the last couple times, I had to cross shipping lanes and just missed a 400 foot ferry by less than a mile. I want to see the ships and ferries (and the other stuff).

Thanks,

Mike
 
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Fishtales

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#4
The hardtops on the GW will work just fine. You can mount to the front edge or if you are concerned use a radar arch. I've done it both ways and both were fine.
 
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#5
We have the same boat and are installing a Simrad 24 on the hardtop. How and where you mounted your Garmin? Did you use a wedge or mount directly to the hardtop. Our hardtop (stock 2006) slants down toward the front, and has no hump. Any feedback and suggestions would be greatly appreciated!
 

Capt Bill

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#10
The transmitted narrow beam angle of radar is typically about 12 deg above and below the center line of the antenna (the radiating element itself). I don't think you needed the wedge, but it should work fine. Ideal mount would be when underway, the radar beam is parallel to the surface of the water; not toward it, and not toward the sky.
 

SkunkBoat

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#11
Its going on a boat. They know that. It will work. it works on every other 20something foot hardtop boat.
garmin and other companies always list a bunch of specs for placement and routing of cables so as to cover their a's when you call them about some problem.
They usually tell you to run the power feed all the way to the battery. Don't be near radios or data cables...blah blah....
I understand it from a tech support angle...you want to know how your product is connected without having to troubleshoot how the boat is wired.
 

Sheepshead

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#12
The transmitted narrow beam angle of radar is typically about 12 deg above and below the center line of the antenna (the radiating element itself). I don't think you needed the wedge, but it should work fine. Ideal mount would be when underway, the radar beam is parallel to the surface of the water; not toward it, and not toward the sky.
Thanks Bill! We measured it while out on the water (stationary) and it was 11deg (top of radar) and 4deg (top of hardtop). The wedge creates more angle than we need and will be remounting directly to the hardtop. Should be just right while underway.