Radar Reflectors

[thataway]

You want a radar reflector to be as high as you can get it on the cabin top--ie just below the radar, or on the arch. On our sailboats I have put the radar reflectors on the mast--at least 40 feet above the water.

There are various studies which come out showing that XXX radar reflector is "best". The small round reflectors have received good reviews--but in the long run, the Davis cheap folding reflector does consistantly well. That is what we carry.

I ran the radar during part of the delta cruise--and all of the C Dories showed up well on our radar, even without reflectors.

[hardee]

A week ago or so, Paul and Verla on the JC Lately and the SleepyC crew were out doing a bit of "radar exercise". With both running radar, at about a mile away, and facing or leaving (directly in line there was a definite scan return that increased slightly when a 90 degree turn was made by the reflecting vessel. We were able to track each other with no problem, but when he got closer (1/4 to half mile from the bank on the far side) he would kind of disappear into that bank. We also noticed that up close 50 - 100 feet the return image would disappear also. That may have been my lack of experience in fine tuning the receiver.

We also tried a 14 x 20 inch cookie sheet, held up flat side toward the scanning boat, with occasionally a slight increase in the return size. Probably due to the inexactness of actually holding it perfectly flat to the scanner-receiver of the observing vessel.

Something I found when rereading this thread, and had missed when thinking about this before. Ours, like most C-Dorys, has a stainless steel sink inside with some reflective surfaces there. Not high off the water, but as the closing distance decreases, that height becomes effectively less necessary for another boat to see it. There are also metal pans and a BBQ on board. Much more metal than I carried on the sail boat.

Many happy returns,

Harvey
SleepyC

[matt_unique]

It is amazing how small a return a large boat will sometimes make. I prioritized a good radar reflector on all my boats. I have used the medium size trilens reflector with excellent results.

[colobear]

I fabricated a radar reflector for C-Cakes and mounted it on the port side of the tall radar arch between to two supports, (pictures on the last page of C-Cakes album). Roger on Dreamer says C-Cakes gives off a good strong blip so that is good. It is not officially approved by any government agency but it makes me feel better. I figure I get about 270 degrees of enhanced reflection. Total cost less than $10.

[hardee]

Wonder if anyone is using this radar reflector from West Marine? And what kind of return improvment it has provided.



WM Radar Reflector Tube M# 10730398 .

I would like to know how it compares with the Davis Echomaster, The 3 flats put together to make a circle, for less money, but it maybe more favorable, for mounting OR how it compares to the Tri-Lens reflectors like this:


for 3 to 4 times the money and more obnoxious to mount.

Harvey
SleepyC

[Mike...]

Harvey, I had a few recommendations to go with the Rozendal Tri-lens reflector (one of those recommendations came from Captain Matt).

As you said, they are obnoxious to mount. The only thing I could come up with was to get two of the small ones and mount them port and starboard, suspended from the underside of the arch. I had to find a solution that dealt with the symmetry issue. It's one of my many hang-ups. .

I haven't mounted them yet, so I can't tell you how well they work yet.
---
mike

[colobear]

When I was looking into putting a radar reflector on c-cakes I read all the reviews of different types I could find. The tri-lens was almost always rated most effective. The cylindrical one least effective..As I posted some time ago I fabricated one for C-Cakes and was pleased with it. A couple of weeks ago I discovered a problem with it. It was mounted on the side of the radar arch and when I pulled the boat to Seattle I just left it up there...mistake. It was not strong enough to withstand the 60MPH winds and one piece broke. So, now I have to spend another $2 for aluminum and make another one. I just accepted that I did not get 360 degree reflectivity by mounting it on one side. Something is better than nothing and I will definitely make another one.

[matt_unique]

I think I mentioned this in another thread but after 10 years use on two boats my Rozendal trilens began to leak rust.

I contacted the manufacturer to ask about whether I could fix it, what I should do, etc. They simply replaced it - brand new - I did not even pay for shipping. I did NOT expect that kind of customer service nor did I ask for it!!!! I would never use anything else between my field experience with the unit and that kind of service.

They lend themselves nicely to a flat mount on the C-Dory roof as you can see in my installations album.

[jlastofka]

I read a Practical Sailor test article a few years back, plus some other test reports that seemed from credible sources. The Tri-Lens was the best, by a good margin. The Davis sheet metal ball (three flat pieces) was pretty good. Every thing else seemed not worth the bother. Some of them really don't work at all.

I have one of the thin tubular Mobri types lying around and I've been meaning to tie it to one of our racing buoys (all plastic) at the yacht club and then motor around it with the C-Dory radar and see how it looks. It was rated poorly.

Also, someone earlier commented about not being able to see targets at very close range. When a radar transmits a pulse, I believe it turns off its receiver for a (very) short time so it doesn't get slammed by high power reflections from extremely close objects, like things on your boat or the one right next to you.

The Davis ball is sensitive to orientation. Having a couple of them, in different orientations would probably be a good idea. It would be neat to mount them inside plastic balls, or a simulated smoke stack for instance.

Plus, there are two radar bands. We use X band (better resolution but sensitive to rain) and the big boats use that near shore, too. Offshore they use S band, which is a different wavelength and these little reflectors are pretty much useless. That's the information I found. If it's out of date, I'd enjoy learning more.

-Jeff

[hardee]

I like the Tri-Lens for it's effectiveness, and maybe the medium one for it's increased image return. I am thinking of mounting it under the radar, and up close, behind (or in front -- but less likely there) the short post that is the current radar tower. Question, Will the effectiveness be decreased, by mounting it that close to that metal post? I am thinking that it would snuggle up close, with the two legs of the "Y" pointing forward at 45's and the other leg pointing straight aft. Any comments? Please.


Harvey
SleepyC

[hardee]

The other option that I thought of is to use two of the tubular ones, and mount them inside, at the aft wall, corners of the cabin. Using two, to increase the return image, since they are less effective than the tri-lens units. That would be less expensive, mounted inside, so less to worry about as to windage, and wear when the cover is on.

Harvey
SleepyC

[marco422]

[hardee]

Any one have any thoughts as to whether the WM tubular reflector can be used, or would be functional if it was laying down in a horizontal position?

Harvey
SleepyC

[Will-C]

Hi,
I bought the Davis Radar Reflector from Defender Marine along with with a U-bolt type mount that does not come with the stainless steel u-bolts. I just u-bolted to my roof rail. I guess it could be higher. Fiberglass does not provide much of a radar target. I hought it would be better to be safe than sorry. It's the high speed ferries that can ruin your day. If you look under photos, then, cruises and events, look for the the Maine Cruise 2010 picture #10 shows what I did right or wrong. Defenders web site http://www.defender.com/

D.D.

[Sea Wolf]