Radar technical bits

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Swanrad2

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Hi looking for some info:
1. Marine Radar emitters- can they be bought stand alone, what frequency do they operate on?
2. What is their physical dimensions withou all the motors and stuff that spin them around? (or is that just the detector)
3. Anyone know a supplier of the bits?

Thanks

Tony
 
Q1. I think that the size of the emitter depends on the size that you want, what range or power output are you after?

Q2, see above

Q3, Raymarine, Furuno, JVC etc etc
 
You're losing me a bit on what you're after here , the emitter is a magnetron that kicks out frequencies comparable to those of a microwave , they can't be sent down a cable as they are too high frequency so have to go down a tube that's designed to bounce the signal along it until it's released . If you give a bit more detail about what you're trying to do it would help
 
I guess there's a wish to make a handheld radar unit. A sort of electronic torch which you wave around and anything at which it's pointing appears on a dinky screen. Jus' like that.

Fries gulls, people'e eyeballs as well.
 
Very much an open question, without more detail, particularly regarding what you want to do with it. Visions of cooking the neighbours by means of a magnetron and a dish antenna come to mind!

If you want to generate RF at X band ie around 10GHz, perhaps to measure velocity by doppler shift, or maybe make a beacon, there are low power Gunn diode modules available for a few pounds - or you can buy the diode and build your own. Would this meet your application?
 
Yes, I am trying to think of a way to press a button and issue a radar pulse that would be picked up by other ship's radars for a small dinghy. Just a DIY bodge up, but keep me busy through the winter.

Sorry I was vague, but it's difficult to ask the right questions when you have not got the faintest idea what you are doing!
]
 
Interesting, at least add a distance finding readout, distance from rocks etc.

Ah, but then you would need to add a receiver, costs, ok, I shall be quiet.
 
If I understand what you are hoping to do correctly, then I am afraid that the ship's radar won't respond in the way that you are hoping.

If you managed to emit on exactly the right frequency as the ship's radar, and point it in the direction at the right time, then the ship's radar would (at most) see something as inteference. Most ship's radars have software that only displays a target when its had a return a few times from a particular point. The algorithms are complex and are designed to clean up the picture.

There are devices around that receive the radar pulse, amplify it and send it back. These work very well, although the design is complicated by the variety and wide rang of frequencies that ships Radars use.
 
What you are really after is a thing called a transponder. These take the incoming radar signal from the other vessel, put a code on it and retransmit it back in such a way that it appears brightly on their screen. Such things can be made without any sort or power supply which would be handy in a dinghy but DIY design at these frequencies is a bit specialised - but it is do-able if you have the knowledge.

I don't think that is would be legal to make (or more accurately, use) such a device in the UK unless it is legally made and licenced, so any assistance you might get from websites will be limited. You can buy these things but they are expensive and the cost is out of proportion to your application.

I guess you are looking for a project rather than have a need for this device anyway but just to put your mind at rest, you shouldn't normally have a need for a device to alert 'ships' to your presence in a dinghy - it would normally be smaller vessels such as yachts and fishing vessels.
 
It's possible that you're thinking of the 'ping' feature that can be used on sonar , this doesn't work on radar because it's filterred and put through so many processes that a ping wouldn't show up at all
 
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