Radar micro waves

BarryH

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Just got the radar arch that was ordered before christmas, was promised delivery by the end of january. That aside, the pratt has made it 12 inches too short. Not a massive problem as it still has a headroom of 7ft 6. The thing that I'm not sure about is how dangerous is the signal from your average radar. Theres been a lot in the press latley about mobile phones and the danger of brain damage!!

I aint gonna pay the bloke if it is'nt any good to me. What sort of distance do you think it should be away/above peoples heads.
 

jfm

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There was a longish thread on this, a year ago, with lots of tekky info ("Do radars fry your brains")

Imho the output is tiny. Praps 30 watts, to which you are exposed for 5/360 of the time (assuming your head subtends an angle of 5 degrees at the radar emitter) which isn't much, though more than a mobile phone. However that's if your head is in line with it, actually the horizontal beam angle tends to be small too, so if your arch is 7'6" you may be below the beam.

Otherwise fit a post and lift it another foot. Or get a tin hat and wrap your gonads in tinfoil
 

coliholic

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< get a tin hat and wrap your gonads in tinfoil >

Now now John, don't give Pauline any more ideas or poor Mr B won't get any rest.
 

byron

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JFM's reply says it all and I endorse him. However if anything were to be affected it would be the eyes (Cateracts)

ô¿ô
 

ChrisP

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Standing in front of the radar is like standing in front of a microwave oven with the door open. Nobody can give you a sure answer as to how much harm it will do you but they all agree it won't do you any good.
Be on the safe side and follow the manufacturers installation instructions to the letter. Remember 7'6" sounds ok but what will it be when the boat trimms out under way. Advise caution especially where short people are involved.

Regards

ChrisP;-)
 

billskip

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Barry ive seen a lot of boats with radar mounted on the cabin roof..im not saying this is good ..but i do think its possible to buy a shield to fit under the dome..a tv company many years ago had a problem with eht tracking so they cut a hole in the bottom of the chassis..ok..then a customers dog was found dead under the set and we had to call all back and fit a shield...I think there is somthing in this "concern about rf" (and it will be like smoking and asbestos) and other things we are encouraged to do today..in a few years we will told how deadly it is..Imho

Bill
www.aegeansailing.co.uk

www.macsyachting.com
 

BarryD

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HLB - Are you sure the sore head is not from sobering up as Tut cannot keep you supplied with beer whilst on the run?

Barry D.

IMHO & FWIW, NWGOI.
 

KevB

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Rightly or wrongly many boats have their 'Radar Arches' very low. Take a Fairline Phantom or Sqaudron for instance, well below head height when your on the flybridge.
 
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The radar horizon is affected by the height of the radar scammer above the water, so the lower you have it the less you will be able to see with it. I'm not sure if an extra foot or so of height would make any difference but it might...
 

numenius

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What the manual says...

My Koden handbook says "high power microwaves harmful to your eyes. Never approach the antenna within 3 meters (sic)". - Presumably this means on the horizontal plane. There is a notable absence of any mention of height however.
Interestingly, output is only 2Kw and as said elsewhere on this post, your only getting it 5/360 of the time, but obviously its still considered dangerous ( look at the tiny mW output from mobile phones, and yet there is increasing concern about THEM - have you seen those RF brain penetration pictures taken whilst using a mobile? - almost reaches through to your far lughole! Scary stuff. Tim Bartlett's book Radar For Small Craft says that most radars are between 1.5 and 5Kw that the average (peak) output is around 3w.



http://members.lycos.co.uk/boaty1965/index.htm
 
G

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During may days in the RNR, going atop whilst the radar was on was considered a "radhaz." Normally with this type of radiation, the intensity is proportional to the inverse square of the distance between the source and the recipient. Doubling the distance quadruples the reduction. 30 W doesnt sound like a lot to me. All IMHO

Robbie W
 

jfm

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Re Misleading output figs

numeris the 2Kw or 1.5Kw type numbers are misleading. They are the peak output. The RMS output is tiny, a few watts only, I think I said praps 30W but it's probly less than that even.
 

BarryH

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so it seems that frying the eyeballs of the short people is not a good idea then. So its a case of get the scanner up the extra foot or so on a pole or send the thing back to the twat that made it and get another one. Why aint anything in life easy anymore!!
 

Medskipper

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Hi Barry

Yes Ive been told that its very bad for the eyes and in prolonged exposure to the rays will lead to blindness! So dont take any chances.

Having said that I dont have a radar screen on my flybridge, its below and when the weather is fine I am always controlling the boat from the bridge so my radar is never on anyway! When the weather is awful and I cant see much I need the radar, but Im not likely to be controlling from the bridge then anyway so even if my radar arch was low its never going to affect my eyes because its not on until I am controlling from below! I thought probably most peaple did that??

Barry
 

BarryH

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Ah but, I have'nt got a flybridge thats the prob. I think the answer is to send it back to the guy that fabricated it and get him to make it to the original dimensions I gave him.
 
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