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Radar Positioning, Which is Best


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Morning folks.

 

We are upgrading our radar from analogue to digital (Raymarine) and the current transponder is on a pole bolted to the transom. As we have recently added a boarding platform and want to free up access space we are planning to move it to the mast .

 

The geometry all checks out so it will fit  ok with adequate sail clearance etc.

 

I would be interested to hear of the pros and cons with having it on the mast as opposed to the transom. Matt ..........? :-)

 

chrs

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Look into and assure yourself of the cable run before commiting too much. Getting it down inside the mast will be tricky if there is no conduit opening at the mounting location. Ideally it would be in a tube inside the mast like the rest of the wiring will be, unlikely to be an option for you without taking the mast out. You will then need to run it down the inside without wrapping it around halyards and get it to pop out the bottom, can be tricky and your left hoping for no damage. Running it down the outside isn’t pretty, and leaves it very exposed to damage as well as the sun.

 

Agree with MH otherwise, slightly better performance, less crew nuking, windage / weight aloft, hard to work on should only be to fit, fairly reliable after that.

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The quantum units are OK, and a mast mount is fine, provided cable can fit.

The images from them are not as good a sthe navico broadband ones though.

I have sample pics from both (and furuno) if anyone is interested.

Power requirements of these radars, and radiation from them is WAY less than the old magnatron based units.

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The quantum units are OK, and a mast mount is fine, provided cable can fit.

The images from them are not as good a sthe navico broadband ones though.

I have sample pics from both (and furuno) if anyone is interested.

Power requirements of these radars, and radiation from them is WAY less than the old magnatron based units.

 

Agree, I'm not sold on Raymarine at all they bloody rushed this last gear update it seems and I have not had a reliable run from their software, it's buggy and crashes often.  Chartplotter reboots randomly from time to time.  One thing to save room is that if you use the Wifi only connection to the Radar you can get away with two core rather than the bloody big fat cable they supply which is not tinned cable (another unbelievable point in my opinion).  

 

These suppliers seem to be on a rush to the bottom with product quality I think.  We pulled one of their chartplotters apart here at work, nothing to them.  

 

I was told that if you put it on the mast you will get a better picture quality if it's lower than higher up the mast.  I'm about to find out as I'm relocating mine lower in the rig.  

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An interesting point is that, with the Navico broadband, you can’t use wireless - simply because the radar produces too much data for a wifi link, it needs the bandwidth of the real cable to work properly.

Yes, you can have the radar too high on the mast. Small vessels move a lot, and it’s harder for the radars to get a decent image when that they are swaying around.

Read your install manuals, they tell you what’s best for your model...

Agree about non tinned cable, it’s crap.

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Interesting about the WiFi data IT.  I upgraded my MFD to a Raymarine es12 and was looking at the radar but decided it was too bloody expensive given my existing one works fine and hardly gets used.  As my old Raymarine MFD wont talk to the new one, I kept the old one just for radar and back up GPS/plotter.

 

I will do the radar in a year or so, but it sounds like I might need to run a new cable.  I have read of issues with the WiFi stability too and I would have thought it is guaranteed to drop off just when you need the radar the most!

 

So far I like the new MFD, especially the big screen :).  I have not upgraded from Lighthouse 2 to 3 as it does not seem to have as many features which is weird.

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I always suggest just above the lower spreaders on a twin spreader rig.

This seems to be the best compromise of height versus rolling/pitching.

Because radar dosnt see over the horizon, its no point having a 24 NM radar 2 metres off the deck.

(Unless you only want it for close quarters and weather watching)

Much higher and on the average yacht the arc of movement can become to great for good resolution.

As above with emissions from newer units.

B n G radar using their own brand wifi transmitter will overlay on open CPN...(and you can use the open CPN controls on it..

Its fantastic on a cheap wide screen TV/monitor .)

Add a wireless mouse and its all you will ever need below decks. (Use the MFD at the wheel for data)

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We got lucky. There was conduit and with some silicone (which is magic for running cables) we got the power cable down no issue. We didn't run the data cable, and I don't think we would have got it down either.

 

Our Axiom Pro has been very stable with no reboots.

 

Used a scanstrut SC20 for mounting to the mast with radar guard. As suggested it is just above the spreaders.

 

Yet to have a good play - but here are a few pictures, which were with a bunch of other boats around on moorings.

 

 

ScreenShot002.png

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A bit more video of it here. Small target detection (like in moored boats) varies considerable between say 1nm range and 1/4nm range, so sometimes you may not be sure what your looking at until you get closer and dial down the range, but then again I am pretty new so stil learning.

 

 

A sort clip I made. The tracked target is a 20 foot yacht.

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Just adding to this thread. Are the extra $$ for a scanstrut gimballed mount really worth it? Just thinking about a Halo24 for Firefly. We've a reinforcement about 4m up the mast and a mousing line, but tossing up between a bespoke carbon mount (from mast manufacturer) and a scanstrut. I'd like not to drill additional holes in the mast. 

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The Halo 24 (or the 20+) are great radars - IMO the best out there. If you intend to use the radar while sailing, a gimballed mount certainly increases the usefulness of the guard zone area, so its not looking at the sky on one side and the sea on the other when heeled more than 15 deg!

The Velocity track on these radars is cool - targets moving toward you are displayed in a different color, so with a glance you can see the ones that may be a collision risk, and then track them with MARPA, to get similar info that an AIS gives you - without any gear required on the other boat! 

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Looking back I am still happy that we didn't go with gimbals. The Scan strut gimbal mount is very pricey, and I decided against it on both financial reasons and that its another moving part which could fail. Alll the flexing wouldn't do the cable much good either.

Looking back - the only thing I might do differently is mount the radar a little lower - as IT pointed out less movement probably helps with a better image. I might consider a pole on the transom, as we have ours near the first spreader we loose small close targets at slightly under 10m.

The beam is sufficiently wide (24 deg rings a bell) that even when heeling quite a bit it seems to work OK for other boats and buoys.

I don't use the doppler mode much, as the color pallette takes away more than gives back in terms of relative motion - but you can get relative velocity vectors which is another way to show the same thing. The Quantum doesn't do dual range - IT I'm sure will advise re HALO if it can.

Also check carefully about you particular brand of mast versus scanstrut hardware - we have a older kemp mast and found out that there was a special scanstrut part we had to use for our radar guard to fit the Selden/Kemp mast shape.

Hope this helps.

 

 

 

 

 

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Unless you can do a direct comparison, you don't get to see the difference.

I decided that the scanstrut was too expensive, so i made my own. Its not perfect though, a mk2 would be better! The current one used teflon bearings - changed 1x (so two bearings in 30 odd thousand miles, now needs another...

If you make one, be certain to get the angle right so there is no rotation in the horizontal axis with heel - it must be exactly right and parallel with the boats water plane for and aft, if you want to use accurate radar overlays. Mine is slightly out.

The issue with non gimbal ones is that you dont know what you cant see! If you have a gimbal one that can be locked level, then you can see the difference!

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Sounds like we agree on the price side of things!! There were the other reasons I went against gimballed. 

Is your mount dampened? How did you do it?

Do you normally alter your G/SC settings or find that auto does a good enough job?

 

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Not dampened, works on gravity only, with a bolt through the gimbal with nylock nut, teflon washers, nut tension sets resistance. I've never thought it needed better dampening. 

Auto settings are usually ok, but occasionally I change them when looking for something specific.

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3 hours ago, Island Time said:

Not dampened, works on gravity only, with a bolt through the gimbal with nylock nut, teflon washers, nut tension sets resistance. I've never thought it needed better dampening. 

Auto settings are usually ok, but occasionally I change them when looking for something specific.

Got some photos somewhere, Matt?

 

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