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Discussion Starter #1
I've pretty much decided, until I change mt mind again, to mount my 2kw radome on the mast of my crealock 31. If I mount it at the spreaders it will just be over the deck light, seems like it may be too close and may interfere with the top of the staysail. This is 18' off the deck. If I mount it over the tang of the inner forestay then it will be 26' high on a 37' mast, seems too high.
Another option would be to mount it under the spreaders and away from the top of the inner forestay but this would block the deck light.
Does anyone wish they had mounted the dome in a different location on the mast?
 

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Coastal Carolinas
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Steve,
We installed the mast mount just above the spreaders on our 34. I added a roller furling unit later on the staysail and it was a bit close to the radome but still workable. Mounting it higher would add more weight aloft without much benefit in range. Everything is a tradeoff but all things considered, I still prefer mast mount over pole or backstay mount.
John
PSC 34 "Norstar"
 

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I have similar plans, except I want as much range as possible and have been asking "why not" mount the radar very high up.

There's another recent thread that covers some this. Search for "radar" would probably show it.
 

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I have similar plans, except I want as much range as possible and have been asking "why not" mount the radar very high up.
Bene,

Sometimes too high can limit your view of close-in targets. Get some good info on this before you decide placement.

Steve,

I don't have an exact hight measurement on our antenna, but as you can see from this photo it is mounted a few feet below the spreader. It has never interfered with our roller furler staysail (not shown). A previous owner installed it, so it's a mid-90's vintage unit, but we've been happy with the performance.

P.S. Forgive the two-tone canvas -- we are in the process of converting over to the khaki.

 

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Discussion Starter #5
JohnRPollard;41836 Steve said:
http://farm4.static.flickr.com/3125/3114156031_b71c792dfa.jpg[/IMG]

Hi John,
Nice pic, Is it a problem for you that the deck light is blocked by the dome?
BTW we chose toast for our canvas, the kaki does look nice with the striking green topsides.
 

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Bene,

Sometimes too high can limit your view of close-in targets. Get some good info on this before you decide placement.
...
You know, I've actually been thinking about the mast track that I have. I could conceivably mount the radar above the deck light and adjust it for the height that I want. And if that height doesnt work (e/g too high for close-in), I can adjust it until it's about right.

Does anyone ever use the mast track that's intended for spinnaker poles, for mounting their radar?

I would think they are strong enough considering the forces that spinnakers put on thier poles.
 

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Discussion Starter #7
I have similar plans, except I want as much range as possible and have been asking "why not" mount the radar very high up.

There's another recent thread that covers some this. Search for "radar" would probably show it.
Hi Bene,
Weight aloft is a concern for me esp since my boat is small, I was seriously considering a stern ploe mount just for this reason. Since my mast is deck stepped I will have to get a DRI PLUG so I can seperate the cable when I unstep the mast.
 

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Discussion Starter #8
Steve,
We installed the mast mount just above the spreaders on our 34. I added a roller furling unit later on the staysail and it was a bit close to the radome but still workable.
John
PSC 34 "Norstar"
Hi John,
If you had it to do over again, would you move the dome lower?
 

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Hi Bene,
Weight aloft is a concern for me esp since my boat is small, I was seriously considering a stern ploe mount just for this reason. Since my mast is deck stepped I will have to get a DRI PLUG so I can seperate the cable when I unstep the mast.
Giuletta started a good thread on that too, it's only a couple weeks old. There were some good ideas passed around. He was/is looking for a removable stern mounted pole.
 

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Hi John,
Nice pic, Is it a problem for you that the deck light is blocked by the dome?
BTW we chose toast for our canvas, the kaki does look nice with the striking green topsides.
Yes, it was a problem, so a new deck light was installed below the radome. Problem solved.:)

Our canvas is "toast" also, I guess I was just referring to it generically as khaki.

Unfortunately, the topsides are only striking after a recent buffing!:(
 

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Bene,

Sometimes too high can limit your view of close-in targets. Get some good info on this before you decide placement.

Steve,

I don't have an exact hight measurement on our antenna, but as you can see from this photo it is mounted a few feet below the spreader. It has never interfered with our roller furler staysail (not shown). A previous owner installed it, so it's a mid-90's vintage unit, but we've been happy with the performance.

P.S. Forgive the two-tone canvas -- we are in the process of converting over to the khaki.


John,I think that where you have your radar is the best spot. On my boat I put forespar spreader lights and foredeck light well below the radar and below the lower spreaders.
 

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I don't want the radar to be permanent and most defenately dodn't want it spoiling my beautifull extremely nice mast..also don't want the weight aloft, and the way my genoas are cut would make it a nightmare.

So my solution had to be a lightweight removable stern pole.


I ended up buying a stern pole for my new radar, including a gimbal and swivel base, that allows easy removal.

I had it all built in carbon Fiber, which is what I wanted for several reasons.

But While looking I saw complete poles sold from around $700 for a basic SS system (Waltz, Edson), $2600 For an all alu gimbaled swivel base at Seaview PYI, to $3600 for a custom, CF system.

The most basic where a simple SS tube with no gimbals and a crude base, and brackets,more complex all alluminium systems with gimbals, base and supports to push pit etc, and really nice one all made in CF..

If you look around you have sveral rather cheap solutions, and you don't have to sacrifice performance by installing the "pressure cooker" on the mast...besides looks ugly. (my opinion).

Mine will be custom made by Seaview PYI and even the gimbal is carbon fiber.

A few sites for you to look for..

SEAVIEW PYI

WALTZ

EDSON

SCANSTRUT

GARHAUER
 

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Coastal Carolinas
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Steve,
I definitely would lower it just below the spreaders just like that pretty green 31 in the above photo. When we installed our unit, I was replacing an older Raytheon unit. We used the same mounting holes as the last bracket. (I hate drilling more holes in the mast).The new Raymarine unit wired to a C80 has worked flawlessly.
John
 

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Would you put a radar stern pole on this ? Don't think it would look very good aesthetically. You can get carbon radar brackets for masts. One thing I don't like about stern poles is having the scanner closer to my head. Just my opinion.
 

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P
would you put a radar on a mast on this???
Nah, it would probably tip over!! :D :D :D :D

Hehehehe.:D

I actually think a mast-mount looks much cleaner than a stern-pole installation. But there are benefits to using a stern-pole too, which can serve other purposes. If I were installing the system today, myself, it would be a real dilemma where to put it. But cost would be a big concern, and the mast is probably the least expensive option for mounting.

Different boats, different budgets, different solutions.
 

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John..you know that my issue is removing it for racing, BUT when I sail and the radar stays, I need it to be light.

Punching holes in my mast is not an option...

you know that
 

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OK, I'm tired of hearing about this losing targets in close if the scanner is mounted on the mast. Personally, I think if you're using radar for things much under a mile you're playing things a little loose but maybe that's just me.

So whom has one on the mast and exactly how close to the boat do you lose return? And, once you've told me that distance, please tell me exactly what it is you're tracking at that range. I am indeed most curious about this.
 

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John..you know that my issue is removing it for racing, BUT when I sail and the radar stays, I need it to be light.

Punching holes in my mast is not an option...

you know that
Yeah, I know. I was just teasing you.:) Pole mount makes good sense in your case. A PSC doesn't have that issue with the mast -- won't even notice the weight of the scanner -- so mast mounting is a viable option. It would be nice to gimbal it, though, regardless of the location.


OK, I'm tired of hearing about this losing targets in close if the scanner is mounted on the mast. Personally, I think if you're using radar for things much under a mile you're playing things a little loose but maybe that's just me....
Sailaway,

You're right, I wouldn't want to detect a ship for the first time at a mile out. But unlike merchant ships, a lot of our radar use on sailboats is close-in work, for picking up buoys and fishing boats in fog, for instance.

In any case, I was responding to Bene's comment (quoted below), and didn't want to embrace the idea that higher is always better. I think there is a practical limit to that approach, both with respect to weight aloft and close-in range. Also, if I have to choose between maximum range to see what might be out at the 20-mile radar horizon, or maximum resolution for close in targets -- I'd choose the latter.

My understanding is that the smaller scanners typically used on sailboats (like the 2KW antennas) don't have the same bandwidth as the larger antennas and can lose targets close-in if mounted too high up. Raymarine or Garmin should be able to answer that question. Maybe Bene and Steve can get some solid info on that and add it to this thread?

As I said, mid-mast is a good spot for most folks, but there are valid reasons to do it differently...


I have similar plans, except I want as much range as possible and have been asking "why not" mount the radar very high up....
 

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From my Radar manual, I copied this page.

This to show that the commonly light vessel radars 2 and 4Kw, are normally 25 deg field of view radars. and installation should be such that it clears the bow of the boat, assuming the lower band of the beam is shot at 12.5 deg from horizontal.

As you can see by the photo bellow, Raymarine does not want mast top mounting, and does not want deck level installation either.

From my conversation by phone with Raymarine US tech service, (very nice excellent guy), and for my case, with a 65 foot mast, it should not be above mast mid height (35 feet in my case),and not bellow 6 feet from the head of the helmsman.

So mine is 13 feet above deck, where they recommended. So radars are ok, if installed between 14 and 35 feet above water, more or less.

Also, because my boat heels a lot, they recomend that over 20 deg heel, the radar be gimbaled.

 
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