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Radar reflectors


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No problem with positioning a radar reflector near a GPS receiver provided it is not so close to the GPS unit as to prevent it seeing large angles of sky. Don't place the radar reflector close to and horizontally in line with a radar scanner if you have one, it will great a shadow area for the radar and could cause problems with the radar receiver. Above the radar scanner is ok or failing that a few feet away horizontally.

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or failing that a few feet away horizontally.

I hope you are joking?

 

As you highlight you are going to create a huge blind spot doing this.

 

Whilst you may not be able to avoid a support post a few feet away I wouldn't want a reflector anywhere on the same horizontal plane (or working plane) as the radome.

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or failing that a few feet away horizontally.

I hope you are joking?

 

As you highlight you are going to create a huge blind spot doing this.

 

Whilst you may not be able to avoid a support post a few feet away I wouldn't want a reflector anywhere on the same horizontal plane (or working plane) as the radome.

Unfortunately not joking. It is "highly desirable" to keep a radar reflector completely out of the transmitting aerial near field but with the constraints of a small boat this is not always practicable. IF the scanner and reflector cannot be positioned vertically with respect to each other then the maximum practicable horizontal separation is the next best option, a couple of feet up or down isn't going to make much difference in this case. The further apart the less the shadow and the lower the amount of transmitted power squirted straight back into the receiver (if the reflector has significant nulls one of the nulls could be aligned with the scanner for a bit of benefit).

 

For peace of mind the reflector should be permanently mounted, not deployed just when conditions seem a bit iffy, but I for one don't fancy the mechanics of mounting a 5Kg reflector at the top of a long pole ohmy.gif and having to lower it every time I want to go under Poole Bridge sad.gif

 

My temporary solution since fitting the radar is a lightweight reflector on a removable pole within the scanner swept area - I'll practice what I preach when better reflector options come on the market biggrin.gif

 

Most raggies use a very substantial metal pole (aka the mast) to mount their scanners on and consequently suffer large angles of radar shadow and reflected energy from it. Their radar reflectors are usually mounted further up the mast above the scanner or swinging in the rigging. I don't think my suggestion will be any worse than this arrangement.

Edited by AHoy
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putting aside the practical differences in use between yachts and small powered fishing craft your own practical solution 'in play' seems much more sensible.

 

as a small powered craft I am always active/defensive when running under radar and passive when at anchor. In fact I am toying with a circular black radar reflector to double as an anchor ball for mounting on said post etc

 

I too had to make the decison about mounting my radar in an optimum for usage or with regard to Poole Bridge - I am no longer able to run under the bridge except at low water.........

 

 

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I read some where that cd dics are as good as any of the radar reflectors

 

will try it one day when the fishings slow that will be the next time ime out.

 

does a radar give off any signal to others?

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I read some where that cd dics are as good as any of the radar reflectors

 

will try it one day when the fishings slow that will be the next time ime out.

 

does a radar give off any signal to others?

not really as they are small and extremely omnidirectional. you could make a mini radar refector out of them I suppose.

 

radar doesn't show on radar - racon's do and you can also get a device that will read radar signatures and give you rough distance and direction. some blue water crusing yachts like these as they don't draw much current and when they chirp into life (audio) they announce the presence of another boat (if it's transmitting with radar of course!)

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  • 4 months later...

So does anybody have a recommendation for a decent radar reflector for my Warrior? Until last week I had a Plastimo tube-type mounted on the gantry opposite my VHF aerial. That was neat and cheap, but ultimately nasty as the plastic tube fell in bits and disappeared while towing the boat home.

 

I'm loathe to replace it with the same again - not because that would probably fall to pieces too, but mainly because I read the test report done by QinetiQ as part of the Ouzo investigation. That report said the Plastimo tube was so poor at angles of even 1 degree as to be almost useless. And they tested the 4" tube- I had the narrower 2", which would be even worse.

 

Suggestions please...

 

Duncan

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I'm still taking stick from having the most expensive passive radar reflector in Cobbs Quay. dry.gif

 

As I keep telling people the Cyclops 3 is the only Passive one that meets the current performance requirements as stipulated by the international marine organisation. cool.gif

 

And if I have the return echo of an aircraft carrier all the better!!! biggrin.gif

 

My recommendation would be one of the Cylops range see link

 

http://www.northseanavigatorinc.com/cyclops%20models.htm

 

obtainable through the manufacturer as per link

http://www.cyclopstech.co.uk/index.html

 

It works on both old X band and S band Radar frequencies

 

If they're good enough for Sunseeker their good enough for me laugh.gif

 

Peteg

 

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The recommendations within the Ouzo report still hold good.

 

I agree that the Plastimo tubes give next to no echo, and the bar has been raised regarding what is acceptable. At the moment, "radar reflectors" are being sold that do not meet the required standard, thereby adding to confusion.

 

Personally, all I can advise is get the best you can afford, and make sure it's correctly mounted in poor visibibility - if not permanently.

 

Having had a number of close encounters of the large fast shipping kind both inshore and offshore in moderate and poor visibility, I'm glad my radar echo is good - and has been checked!

 

Mike

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Plastimo no longer make the plastic tube reflectors you'll be pleased to know. I recently bought a traditional diamond-shaped reflector as I need one for Guernsey commercial regs, it's currently sat in the cabin awaiting mounting - I just have to work out how to fix it above my radar which is sat on top of the arch.

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Paul,

I havent gone mad with the mounting height see pics.

I am aware that there is some shadowing due to the mast forward however hopefully I will be looking where I 'm going as well hence minimising risk.

 

The main reflection lobes are to the side rather than for/aft (although even these still meet spec)

 

The beauty of this device is that it also takes a Nav light fitting bolted to the top such that the cable can runs straight through the body of the unit and out of the bottom.

 

For those of you with Radar arches it makes it easy to mount both cyclops and nav light as one peice.

 

Hope This helps

 

By the way I have no affiliation with the company its just that I spent a lot of time trying to find a unit that would comply with current specs.

 

The spec will be changing soon and becoming even more challenging to match.

Cyclops themself are developing a brand new design but are awaiting material prices to drop before committing to market so don't hold your breath

 

Pete

post-6-1220389610jpg

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