How powerful is your radar ?

[heimdal]

I reckon this one could make toast.

http://www.newsinenglish.no/2012/10/16/us-admits-to-radiation-incident/

 

[LadyInBed]

The more powerful the more juce it sucks
I don't want to see more than six nm, occasionally take a squint at twelve

 

[Three kings]

4Kw HD Colour - squall spotter supreme

 

[single]

Remember that report is by the media so ignore most of it.

 

[BelleSerene]

No radar's going to see over the horizon (not the wavelength we all use for it, anyway) - so there's no point upping the power of your radar unless you're going to stick it even higher up a mast.

If you're worried about radiation from the radar, perhaps best to avoid mounting it on a strut off the pushpit. The radiation'll go straight into your head, and at point-blank range. As the pattern of radiation is a sideways cone, the further up you put it, the less radiation you get down in the cockpit. Locks create an exception - the radar waves bounce back off the lock walls - which is why there's usually a sign by a lock asking you to turn your radar off before entering.

 

[pvb]

If you're worried about radiation from the radar, perhaps best to avoid mounting it on a strut off the pushpit. The radiation'll go straight into your head, and at point-blank range.

That's a massive exaggeration. The radar beam typically is no more than 12 degrees above and below the horizontal. If the radar is mounted so that the boom isn't in the way of the beam, as it has to be, it's unlikely ever to cause health problems for the crew. Additionally, the power radiated by small leisure radars is minimal.

 

[Fourbees]

I haven't got a radar (didn't seem worth the expense) but for the next boat, when I do Biscay, an Atlantic circuit etc., I'll get one of the 'digital broad band' kind. It seems to me that they create less radiation, use a lot less power and give a clearer picture at short ranges. Combined with an active radar responder and AIS (which I've got even now) and I reckon I should be OK. Unless you know differently....

 

[emsworthy]

If you're worried about radiation from the radar, perhaps best to avoid mounting it on a strut off the pushpit. The radiation'll go straight into your head, and at point-blank range.

Snooks has his radar on a wobbly pole on the pushpit and he seems fine... doesn't he? No sign of a fried head at all.

 

[johnalison]

"Skin felt warm" and "complained of headaches". This seems rather a long way from being injured as was claimed.

For yachts the radar power probably has no significance. My current one is 4Kw on a stern pole but the previous 2Kw was more than adequate and was able to see ships at 15+ miles and pick up birds and unoccupied moorings at close range.

 

[Plomong]

That's a massive exaggeration. The radar beam typically is no more than 12 degrees above and below the horizontal. If the radar is mounted so that the boom isn't in the way of the beam, as it has to be, it's unlikely ever to cause health problems for the crew. Additionally, the power radiated by small leisure radars is minimal.

But for a powerful radar sidelobes could be significant, not in relative terms, but in absolute.

Plomong

 

[pvb]

But for a powerful radar sidelobes could be significant, not in relative terms, but in absolute.

Are you talking about leisure boat radars?

 

[Beadle]

I used to work with someone who had been a "sparks" on a cable ship.

The whole crew used to stand in front of the main radar before going ashore to do what sailors do after several weeks at sea. Claimed it prevented leaving any little gifts a few months later.

Don't know if it worked

 

[Relax]

A long time ago I worked for a bit at RAF Lossiemouth.

The air traffic control radar had an arm-thick 11kV cable going into it - where does it go?

Damn sure I never sttod near it when it was on.

 

[AntarcticPilot]

I once spent about a month at DYE3, an early warning radar station on the Greenalnd Ice Cap. The system was still in operation at that time, though civilian manned. The guys manning it were far more interested in watching bird migrations than the aircraft they were supposed to be monitoring!

It was strictly forbidden for people to be on the deck where the radar antennae were situated, as the radiation was reckoned to be at harmful levels.

I was operating an ice sounding radar, which used a VASTLY different operating frequency. We first of all found that the digital recording equipment wouldn't work anywhere near the station until we covered the mobile cabin containing it with aluminium foil. And despite the vast difference in frequencies, we found that the system still picked up a lot of interference from the radar. Fortunately, the nature of the interference was such that we could filter it out!

I don't know if it was the insulating value of the aluminium foil or the heating effect of the radar, but it got extremely hot in that cabin! And the outside temperatures were around -10 to -30 degrees C. Not the power of the equipment we were using; it was powered by two truck batteries that gave an operating life of perhaps 8 hours (we never ran out of battery power,so I don't know the exact figures). But the total consumption was a few hundred watts.

 

[Plomong]

Are you talking about leisure boat radars?

Obviously not,

but then the OP's reference was not a leisure radar, was it ?

 

[st599]

I haven't got a radar (didn't seem worth the expense) but for the next boat, when I do Biscay, an Atlantic circuit etc., I'll get one of the 'digital broad band' kind. It seems to me that they create less radiation, use a lot less power and give a clearer picture at short ranges. Combined with an active radar responder and AIS (which I've got even now) and I reckon I should be OK. Unless you know differently....

2kW at a small duty cycle versus 100% duty cycle at a small power.

I bet the power radiated isn't very different.

 

[pvb]

Obviously not,

but then the OP's reference was not a leisure radar, was it ?

I'm sorry, but I don't understand then why you replied to a post of mine which was obviously about small boat radar, as it was in response to BelleSerene's dire warnings about pushpit pole-mounted small boat radars.

 

[Conachair]

I haven't got a radar (didn't seem worth the expense) but for the next boat, when I do Biscay, an Atlantic circuit etc., I'll get one of the 'digital broad band' kind. It seems to me that they create less radiation, use a lot less power and give a clearer picture at short ranges. Combined with an active radar responder and AIS (which I've got even now) and I reckon I should be OK. Unless you know differently....

The fast start up time sounds major bonus as well, when you just want to have a quick peek at something.

 

[penfold]

"Skin felt warm" and "complained of headaches". This seems rather a long way from being injured as was claimed.

For yachts the radar power probably has no significance. My current one is 4Kw on a stern pole but the previous 2Kw was more than adequate and was able to see ships at 15+ miles and pick up birds and unoccupied moorings at close range.

There is rather a large gap between a 2kW leisure/commercial radar and a AEGIS radar system; the AN/SPY1 has a peak output of 6MW; it's more than capable of injuring at significant range and could easily kill.

 

[LadyInBed]

I'll get one of the 'digital broad band' kind.

According to this dated July 2009 “Broadband Radar” is Navico’s registered trade name for it’s Frequency Modulated Continuous-Wave X-Band Radar, sold under the Lowrance, Northstar and Simrad Yachting brands.

Accordingly the term "Broadband Radar" is technically meaningless, and your search should include the terms Frequency Modulated Continuous-Wave (FMCW).

technical review by Prof. Bill Mullarkey of dB Research
Note in 3.1.1 he says "Energy NOT Power
Please note that it is the energy that matters when considering target detection not the peak power."

(Searching for Frequency Modulated Continuous-Wave Radar brings up several useful links.)