seame - anyone have experience that it really works ?

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homa

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I plotted a yacht on radar yesterday up to 7.5 miles with their seame confirmed as working.
Sea surface was flat and I could still pick up other yachts without seame at a similar range.
I was surprised that it didn't show the yacht (with seame) as a stronger target compared to other similar sized yachts.
The experiment was very inconclusive as the sea conditions were so calm that anything was going to show up well on radar.

Anyone have experience good or bad ?

A seame was on my wish list for this winter - I'm not so sure now.
 
I have read some of the comments on seame but no-one appears to have actual experience of whether it actually works any better than a passive reflector.

I was surprised yesterday when the return from the boat with seame was no better than others without. But as I said it was perfect conditions and anything would show up. Just expected the seame to be a stronger target response than it actually was
 
We use it on the daughter RIB and it gives us a good strong echo back - much larger and easier to aquire than without it switched on, even when the RIB is travelling at speed and in 'cluttery' conditions.

W.
 
Yes, that's the issue.

As far as I can see, SeaMe is a transponder; it receives a radar pulse in the marine band and transmits back a pulse, much like the transponders fitted to buoys, LVs etc. As we all know, often we have to get very close to the buoy to start the transponder going but when it does the effect is incredible.

As you say, having bought one, how can you tell that it is responding adequately to incoming signals AND transmitting back an appropriate pulse that will paint on the other vessel's radar screen?
 
You may care to look at earlier entries on the Seame. I have had one for something like four years and I believe it to be a brilliant piece of kit that I would hate to be without, especially in areas which are busy with commercial traffic. From rough and ready tests soon after we fitted it we found that higher power radars as found on commercial vessels produced very clear returns. On several occasions we have forgotton to swich it on only to find ourselves being " ignored" by a commercial vessel. Switching it on has produced a rapid change of course by the other vessel so giving us our right of was as stand on vessel. In my view I would fit one before many other items of kit. The only downside is that it only works on one radr wavelength.
 
You saw the boat with the see-me so it did work. You cant really compare different boats - the radar image they reflect is far from being just that from the radar reflector - its all the metalwork on the boat, and the angle of big items to the radar beam will affect the result. Just like they do with the US stealth bomber. In fact this can be one reason why you dont see a boat with a radar reflector - the reflection from the engine cancelling out the reflection from the reflector. Sounds odd I know but it can happen.

The only way to see the effect of the transponder is to see what happens to the echo of that boat when you switch the transponder on and off.

Assuming the transponder is working then it has to improve the situation. A reflector can only send back what hits it. The transponder takes what hits it, amplifies it and then sends it back. So it has to be a good idea. How well the specific electronics work is a different issue.
 
The radars I am using are on a commercial vessel (one X band and one S band)
The radars are both 6 months old and were tuned in properly.
I was surprised by the average response yesterday. I had expected it to be better.
I will look out for another target when the sea is a little rougher. But it is hard to spot the seame aerial and there are not that many boats with them.
it just happened that I spotted this boat with one and I called him up and asked if it was switched on, we stayed in radio contact as I steamed away from him.

All I am saying is that I was disappointed and had expected a stronger target response.
 
I have seen enough yachts on a radar to know if it is a good or bad return.

I was disappointed that the return was no better than any other yacht in the vicinity.
 
There is an old RF aerial technician's bit of kit made from an LED and a Bic pen (Neons used to be used, and maybe are better). You put the LED or neon in the Bic and attach one leg to a wire that goes down to the end you hold in your hand, and connect the other wire to a bit of stiff tinned copper wire that protrudes upwards, like a radio aerial. Wave that around transmitting apparatus with mean power greater than a few watts and you usually see a glow. Cheap, cheerful, and reliable if it works with that class of kit.

Might be interesting to try it on ships' radars and the SeaMe. Doesn't cost 50p to make or nothing from the gash box. Anyone with a SeaMe like to try it out?
 
I believe the Seame works well having used one for a number of years and had a third party comment on its performance, but don’t take my word for it, read the QinetiQ report on the RYA website at www.rya.org.uk

When on the website under find select “Site Search” and then enter “QinetiQ”

Your should find “Report on the performance of Radar Reflectors ”

It makes very interesting reading especially the Conclusions on page 30 and the Recommendations on page 31.
 
The problem I have is once the ship knows I am there they can see me with or without the Seame on. It is all to do with the operator and the Radar settings. That is why I know ships radars CAN see yachts in bad conditions. Tested on the west coast of the US with a cruise ship.

The only way to really test it, is to ask ships at 5-10 miles away but that is hard. My best call was a ship at 10 miles that had me on the radar but not the other yachts.

The problem is most people think that you will suddenly become the size of a tanker on their screens. This is not true. You are still are a dot appropriate to your distance away and their beam widths. You do not get any wider, fatter or longer.

The aim is to be a more RELIABLE dot.

(Usual warning that X band is not used by the vast majority of the careless ship captains while in open Ocean)
 
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