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Scott Rosen
01-13-2004, 03:51 PM
Iím hoping to buy and install a radar unit this year. Iím looking at two LCD units for small sailboats: the Furuno 1712 and the Raymarine SL 72.

Iíd like to hear from anyone who has experience and opinions on the best radar unit for my use. Iím more concerned with quality and reliability than with bells and whistles. I wonít be needing a chart plotter or anything that fancy.

Also, does anyone know how the heeling and rolling of the boat will affect the radarís ability to light up targets?

Scott Rosen
01-13-2004, 03:51 PM
Iím hoping to buy and install a radar unit this year. Iím looking at two LCD units for small sailboats: the Furuno 1712 and the Raymarine SL 72.

Iíd like to hear from anyone who has experience and opinions on the best radar unit for my use. Iím more concerned with quality and reliability than with bells and whistles. I wonít be needing a chart plotter or anything that fancy.

Also, does anyone know how the heeling and rolling of the boat will affect the radarís ability to light up targets?

Scott Rosen
01-13-2004, 03:51 PM
Iím hoping to buy and install a radar unit this year. Iím looking at two LCD units for small sailboats: the Furuno 1712 and the Raymarine SL 72.

Iíd like to hear from anyone who has experience and opinions on the best radar unit for my use. Iím more concerned with quality and reliability than with bells and whistles. I wonít be needing a chart plotter or anything that fancy.

Also, does anyone know how the heeling and rolling of the boat will affect the radarís ability to light up targets?

Matt J.
01-13-2004, 04:33 PM
Scott,
I'm no expert, and in fact, I've thought of not re-installing the radar next year, as we seldom see fog, and likely wouldn't go out if we did.

Our is a Raymarine, and I think it's the 72. It's a small (maybe 6"?) LCD screen. I've used it for amusement a few times, and was impressed with what it'll see (boat wakes, very small boats, and it nails bouys like nobody's business).

Our delivery captain said it was the best LCD radar unit he's ever used, which means 10X more than my comments.

That's all I've got.

Wanna buy ours?

Matt J.
01-13-2004, 04:33 PM
Scott,
I'm no expert, and in fact, I've thought of not re-installing the radar next year, as we seldom see fog, and likely wouldn't go out if we did.

Our is a Raymarine, and I think it's the 72. It's a small (maybe 6"?) LCD screen. I've used it for amusement a few times, and was impressed with what it'll see (boat wakes, very small boats, and it nails bouys like nobody's business).

Our delivery captain said it was the best LCD radar unit he's ever used, which means 10X more than my comments.

That's all I've got.

Wanna buy ours?

Matt J.
01-13-2004, 04:33 PM
Scott,
I'm no expert, and in fact, I've thought of not re-installing the radar next year, as we seldom see fog, and likely wouldn't go out if we did.

Our is a Raymarine, and I think it's the 72. It's a small (maybe 6"?) LCD screen. I've used it for amusement a few times, and was impressed with what it'll see (boat wakes, very small boats, and it nails bouys like nobody's business).

Our delivery captain said it was the best LCD radar unit he's ever used, which means 10X more than my comments.

That's all I've got.

Wanna buy ours?

Scott Rosen
01-13-2004, 04:36 PM
Maybe. I'll email you. smile.gif

Scott Rosen
01-13-2004, 04:36 PM
Maybe. I'll email you. smile.gif

Art Read
01-13-2004, 04:36 PM
There ARE gimballed units available. Might be a harder installion. Got a split backstay by any chance? That said, the few, fixed units I've used haven't seemed to suffer too badly from heeling. At least for the limited purposes I wanted 'em on for... Simple navigation and big, CLOSE ship detection. :eek:

Art Read
01-13-2004, 04:36 PM
There ARE gimballed units available. Might be a harder installion. Got a split backstay by any chance? That said, the few, fixed units I've used haven't seemed to suffer too badly from heeling. At least for the limited purposes I wanted 'em on for... Simple navigation and big, CLOSE ship detection. :eek:

Scott Rosen
01-13-2004, 04:36 PM
Maybe. I'll email you. smile.gif

Art Read
01-13-2004, 04:36 PM
There ARE gimballed units available. Might be a harder installion. Got a split backstay by any chance? That said, the few, fixed units I've used haven't seemed to suffer too badly from heeling. At least for the limited purposes I wanted 'em on for... Simple navigation and big, CLOSE ship detection. :eek:

Gary E
01-13-2004, 05:16 PM
Heeling over will alter the display,
When do you get enuf wind while in a fog to care?

G

Gary E
01-13-2004, 05:16 PM
Heeling over will alter the display,
When do you get enuf wind while in a fog to care?

G

Gary E
01-13-2004, 05:16 PM
Heeling over will alter the display,
When do you get enuf wind while in a fog to care?

G

Ian McColgin
01-13-2004, 05:22 PM
The gimbaled units are lovely but very pricy. Have to be damped and all.

Don't you have a ketch? The mizzen right near the spreaders is traditional.

I made a wonderful radar attachment for a friend's sloop by taking a dinghey mast and cutting it to fit a neat molded epoxy and filler step - interesting slope - at the backstay chainplate. It fit over the back stay and I made a plug to keep it centered on the stay at the top. This way we got a good firm structure to hold the radar mount.

He had to leave the radar unconnected until the boat was tuned as the rig completely hid the back stay bottle.

Do you need the gimballed unit? Quite possibly not. If the fog is so thick that you really need the scope, you may well be motoring and standing upright.

If you use the radar under sail a lot - now possible with the lower power drain units of the last decade or so - the problem is with seeing things on either side. Not the range, just whether you see it at all. Small angles of heel don't make much difference as the beam has an angular spread anyway, which you can get from the specs. But you could get so far over that the beam on the weather side is more useful for tracking air craft and the beam to leeward is diving only a few fathoms from the boat. Even then, the radar will still find the forward and aft targets just fine.

It takes a while to learn how to read the radar. Headlands show up and the beach does not, making the image different from what you might expect from the chart.

If you get it, use it a lot on nice days when you can confirm visually and get used to how things look in the scope.

G'luck

Ian McColgin
01-13-2004, 05:22 PM
The gimbaled units are lovely but very pricy. Have to be damped and all.

Don't you have a ketch? The mizzen right near the spreaders is traditional.

I made a wonderful radar attachment for a friend's sloop by taking a dinghey mast and cutting it to fit a neat molded epoxy and filler step - interesting slope - at the backstay chainplate. It fit over the back stay and I made a plug to keep it centered on the stay at the top. This way we got a good firm structure to hold the radar mount.

He had to leave the radar unconnected until the boat was tuned as the rig completely hid the back stay bottle.

Do you need the gimballed unit? Quite possibly not. If the fog is so thick that you really need the scope, you may well be motoring and standing upright.

If you use the radar under sail a lot - now possible with the lower power drain units of the last decade or so - the problem is with seeing things on either side. Not the range, just whether you see it at all. Small angles of heel don't make much difference as the beam has an angular spread anyway, which you can get from the specs. But you could get so far over that the beam on the weather side is more useful for tracking air craft and the beam to leeward is diving only a few fathoms from the boat. Even then, the radar will still find the forward and aft targets just fine.

It takes a while to learn how to read the radar. Headlands show up and the beach does not, making the image different from what you might expect from the chart.

If you get it, use it a lot on nice days when you can confirm visually and get used to how things look in the scope.

G'luck

Ian McColgin
01-13-2004, 05:22 PM
The gimbaled units are lovely but very pricy. Have to be damped and all.

Don't you have a ketch? The mizzen right near the spreaders is traditional.

I made a wonderful radar attachment for a friend's sloop by taking a dinghey mast and cutting it to fit a neat molded epoxy and filler step - interesting slope - at the backstay chainplate. It fit over the back stay and I made a plug to keep it centered on the stay at the top. This way we got a good firm structure to hold the radar mount.

He had to leave the radar unconnected until the boat was tuned as the rig completely hid the back stay bottle.

Do you need the gimballed unit? Quite possibly not. If the fog is so thick that you really need the scope, you may well be motoring and standing upright.

If you use the radar under sail a lot - now possible with the lower power drain units of the last decade or so - the problem is with seeing things on either side. Not the range, just whether you see it at all. Small angles of heel don't make much difference as the beam has an angular spread anyway, which you can get from the specs. But you could get so far over that the beam on the weather side is more useful for tracking air craft and the beam to leeward is diving only a few fathoms from the boat. Even then, the radar will still find the forward and aft targets just fine.

It takes a while to learn how to read the radar. Headlands show up and the beach does not, making the image different from what you might expect from the chart.

If you get it, use it a lot on nice days when you can confirm visually and get used to how things look in the scope.

G'luck

Scott Rosen
01-13-2004, 05:28 PM
Thanks for the replies. I donít expect to use the radar under sail much. It would mostly be under power in low visibility conditions.

I donít know about you folks, but Iíve been in thick fog with wind and seas. Iím more concerned with rolling from seas than heeling.

I donít want to buy a gimbaled unit because they are very expensive. My boat is a sloop, and I plan to mount the radar on the mast. Iíd like to have it high enough so that in six to 10 foot swells, the radar unit will stay above the wave tops.

Scott Rosen
01-13-2004, 05:28 PM
Thanks for the replies. I donít expect to use the radar under sail much. It would mostly be under power in low visibility conditions.

I donít know about you folks, but Iíve been in thick fog with wind and seas. Iím more concerned with rolling from seas than heeling.

I donít want to buy a gimbaled unit because they are very expensive. My boat is a sloop, and I plan to mount the radar on the mast. Iíd like to have it high enough so that in six to 10 foot swells, the radar unit will stay above the wave tops.

Scott Rosen
01-13-2004, 05:28 PM
Thanks for the replies. I donít expect to use the radar under sail much. It would mostly be under power in low visibility conditions.

I donít know about you folks, but Iíve been in thick fog with wind and seas. Iím more concerned with rolling from seas than heeling.

I donít want to buy a gimbaled unit because they are very expensive. My boat is a sloop, and I plan to mount the radar on the mast. Iíd like to have it high enough so that in six to 10 foot swells, the radar unit will stay above the wave tops.

Gerald
01-13-2004, 05:51 PM
This is good stuff because I am also wanting to mount a unit on my yawl. My plan was to mount it high on the mizzen mast. Would there be a negative to having the main mast in front of the unit and don't the sails have an effect on the unit? We have little fog but I plan to use it at night and want a unit with an alarm that will wake me if I am closing on something or something is closing on me. It would also be important that it work while the boat is under sail and possibly heeling.
Gerald

Gerald
01-13-2004, 05:51 PM
This is good stuff because I am also wanting to mount a unit on my yawl. My plan was to mount it high on the mizzen mast. Would there be a negative to having the main mast in front of the unit and don't the sails have an effect on the unit? We have little fog but I plan to use it at night and want a unit with an alarm that will wake me if I am closing on something or something is closing on me. It would also be important that it work while the boat is under sail and possibly heeling.
Gerald

Gerald
01-13-2004, 05:51 PM
This is good stuff because I am also wanting to mount a unit on my yawl. My plan was to mount it high on the mizzen mast. Would there be a negative to having the main mast in front of the unit and don't the sails have an effect on the unit? We have little fog but I plan to use it at night and want a unit with an alarm that will wake me if I am closing on something or something is closing on me. It would also be important that it work while the boat is under sail and possibly heeling.
Gerald

Ian McColgin
01-13-2004, 06:48 PM
Sails have no effect and the mast is too close and too rounded to be much interferance - sometimes a feint line on the scope dead ahead.

Donn's point about don't go too high is well taken as near acuity is important. Much over 15' to 20' over the water is not so good in a wee boat.

In big seas there can be occasions when the waves cause clutter - scattered returns. The moments when you're right in the trough don't produce the same sort of clutter.

The rolling of the boat may produce sea clutter that you have to play the gain and such to sort out but it won't create utterly deceptive false targets. There are lots of impulses shot out every microsecond. The gimballed mounts I've seen are hydrolically damped. I don't know if they can keep up with rolling. They were designed for a more normal and constant heel. They were not designed and I've not seen any installed in motor boats, through they also can roll - in fact more badly than a sail boat.

Ian McColgin
01-13-2004, 06:48 PM
Sails have no effect and the mast is too close and too rounded to be much interferance - sometimes a feint line on the scope dead ahead.

Donn's point about don't go too high is well taken as near acuity is important. Much over 15' to 20' over the water is not so good in a wee boat.

In big seas there can be occasions when the waves cause clutter - scattered returns. The moments when you're right in the trough don't produce the same sort of clutter.

The rolling of the boat may produce sea clutter that you have to play the gain and such to sort out but it won't create utterly deceptive false targets. There are lots of impulses shot out every microsecond. The gimballed mounts I've seen are hydrolically damped. I don't know if they can keep up with rolling. They were designed for a more normal and constant heel. They were not designed and I've not seen any installed in motor boats, through they also can roll - in fact more badly than a sail boat.

Ian McColgin
01-13-2004, 06:48 PM
Sails have no effect and the mast is too close and too rounded to be much interferance - sometimes a feint line on the scope dead ahead.

Donn's point about don't go too high is well taken as near acuity is important. Much over 15' to 20' over the water is not so good in a wee boat.

In big seas there can be occasions when the waves cause clutter - scattered returns. The moments when you're right in the trough don't produce the same sort of clutter.

The rolling of the boat may produce sea clutter that you have to play the gain and such to sort out but it won't create utterly deceptive false targets. There are lots of impulses shot out every microsecond. The gimballed mounts I've seen are hydrolically damped. I don't know if they can keep up with rolling. They were designed for a more normal and constant heel. They were not designed and I've not seen any installed in motor boats, through they also can roll - in fact more badly than a sail boat.

mariner2k
01-13-2004, 08:36 PM
I have mine on a mizzen mast about 22' high. I think furuno suggested not over 24'. It works fine. As far as adding weight aloft...that won't matter unless your putting it on a sailing dinghy.
I hardly ever use mine but it sure is nice when you need it. Practice in the good weather.
mariner

mariner2k
01-13-2004, 08:36 PM
I have mine on a mizzen mast about 22' high. I think furuno suggested not over 24'. It works fine. As far as adding weight aloft...that won't matter unless your putting it on a sailing dinghy.
I hardly ever use mine but it sure is nice when you need it. Practice in the good weather.
mariner

mariner2k
01-13-2004, 08:36 PM
I have mine on a mizzen mast about 22' high. I think furuno suggested not over 24'. It works fine. As far as adding weight aloft...that won't matter unless your putting it on a sailing dinghy.
I hardly ever use mine but it sure is nice when you need it. Practice in the good weather.
mariner

PaulC
01-13-2004, 08:59 PM
Are there any concerns for mounting with regard to EMF on captain and crew? It would be a shame to nuke everyone on-board. Some powerboats seem to have them mounted about waist high. It always seems like that is just creating trouble.

PaulC
01-13-2004, 08:59 PM
Are there any concerns for mounting with regard to EMF on captain and crew? It would be a shame to nuke everyone on-board. Some powerboats seem to have them mounted about waist high. It always seems like that is just creating trouble.

PaulC
01-13-2004, 08:59 PM
Are there any concerns for mounting with regard to EMF on captain and crew? It would be a shame to nuke everyone on-board. Some powerboats seem to have them mounted about waist high. It always seems like that is just creating trouble.

JeffH
01-14-2004, 12:09 AM
Originally posted by PaulC:
[qb]Are there any concerns for mounting with regard to EMF on captain and crew? It would be a shame to nuke everyone on-board. Some powerboats seem to have them mounted about waist high. It always seems like that is just creating trouble.Just remember to wear your lead-lined Jokey's ;) In the old days of radar, the working principle was more in the line of brute force over finess. This did create wonderfully sharp and clear pictures, to my eye much better even than anything I've seen on the market now. However, they needed room-sized control units, often with thier own air conditioners, and you could toast marshmellows with the antenna. In these days of modern electronic wizardry, the units have become very, very sensitive and a lot can be done with a little (though with computerized filtering, even the best pictures are fuzzier than they were in the golden age). The latest yacht-sized radars require so little power they can be run on batteries for hours, something unthinkable not too long ago. It is still possible to get a radiation dose at levels above the recommended limits from a modern unit, but only if you are standing within three meters of the antenna, it's transmitting, pointed right at you and not rotating. With a rotating antenna, the exposure actually drops to a safe level, even within a couple feet. One meter away and half a meter below, and you have something only barely above the natural background noise. Basically, most units have a safety limit of 3 meters, since some actually do still transmit while in standby and not rotating. To be safe, say if you're at a pier and a lot of people are at antenna height (or if you're one of those types who must have one of those gowdaful speedboat things), just turn the thing off when it's not being used.

As a licensed, professional radar watcher who has spent many countless (tedious, hideous, horrible) hours staring at these things, I can say that even consistent 30 degree rolls don't noticeably affect radar performance, even at the normal 24 mile scale merchant ships use (of course, the scanners are a hundred feet up). Since the three mile scale is about the upper limit for seeing anything useful on the teeny little radar screens on a yacht, a little heel shouldn't be that much of a problem to justify shelling out the green for a gimbal.

To the original question: In the yacht-size radar department, I've only used a couple Furuno's, which I didn't like since I found them gimicky and non-intuitive. My advice: Simple is good.

Jeff

[ 01-14-2004, 12:13 AM: Message edited by: JeffH ]

JeffH
01-14-2004, 12:09 AM
Originally posted by PaulC:
[qb]Are there any concerns for mounting with regard to EMF on captain and crew? It would be a shame to nuke everyone on-board. Some powerboats seem to have them mounted about waist high. It always seems like that is just creating trouble.Just remember to wear your lead-lined Jokey's ;) In the old days of radar, the working principle was more in the line of brute force over finess. This did create wonderfully sharp and clear pictures, to my eye much better even than anything I've seen on the market now. However, they needed room-sized control units, often with thier own air conditioners, and you could toast marshmellows with the antenna. In these days of modern electronic wizardry, the units have become very, very sensitive and a lot can be done with a little (though with computerized filtering, even the best pictures are fuzzier than they were in the golden age). The latest yacht-sized radars require so little power they can be run on batteries for hours, something unthinkable not too long ago. It is still possible to get a radiation dose at levels above the recommended limits from a modern unit, but only if you are standing within three meters of the antenna, it's transmitting, pointed right at you and not rotating. With a rotating antenna, the exposure actually drops to a safe level, even within a couple feet. One meter away and half a meter below, and you have something only barely above the natural background noise. Basically, most units have a safety limit of 3 meters, since some actually do still transmit while in standby and not rotating. To be safe, say if you're at a pier and a lot of people are at antenna height (or if you're one of those types who must have one of those gowdaful speedboat things), just turn the thing off when it's not being used.

As a licensed, professional radar watcher who has spent many countless (tedious, hideous, horrible) hours staring at these things, I can say that even consistent 30 degree rolls don't noticeably affect radar performance, even at the normal 24 mile scale merchant ships use (of course, the scanners are a hundred feet up). Since the three mile scale is about the upper limit for seeing anything useful on the teeny little radar screens on a yacht, a little heel shouldn't be that much of a problem to justify shelling out the green for a gimbal.

To the original question: In the yacht-size radar department, I've only used a couple Furuno's, which I didn't like since I found them gimicky and non-intuitive. My advice: Simple is good.

Jeff

[ 01-14-2004, 12:13 AM: Message edited by: JeffH ]

JeffH
01-14-2004, 12:09 AM
Originally posted by PaulC:
[qb]Are there any concerns for mounting with regard to EMF on captain and crew? It would be a shame to nuke everyone on-board. Some powerboats seem to have them mounted about waist high. It always seems like that is just creating trouble.Just remember to wear your lead-lined Jokey's ;) In the old days of radar, the working principle was more in the line of brute force over finess. This did create wonderfully sharp and clear pictures, to my eye much better even than anything I've seen on the market now. However, they needed room-sized control units, often with thier own air conditioners, and you could toast marshmellows with the antenna. In these days of modern electronic wizardry, the units have become very, very sensitive and a lot can be done with a little (though with computerized filtering, even the best pictures are fuzzier than they were in the golden age). The latest yacht-sized radars require so little power they can be run on batteries for hours, something unthinkable not too long ago. It is still possible to get a radiation dose at levels above the recommended limits from a modern unit, but only if you are standing within three meters of the antenna, it's transmitting, pointed right at you and not rotating. With a rotating antenna, the exposure actually drops to a safe level, even within a couple feet. One meter away and half a meter below, and you have something only barely above the natural background noise. Basically, most units have a safety limit of 3 meters, since some actually do still transmit while in standby and not rotating. To be safe, say if you're at a pier and a lot of people are at antenna height (or if you're one of those types who must have one of those gowdaful speedboat things), just turn the thing off when it's not being used.

As a licensed, professional radar watcher who has spent many countless (tedious, hideous, horrible) hours staring at these things, I can say that even consistent 30 degree rolls don't noticeably affect radar performance, even at the normal 24 mile scale merchant ships use (of course, the scanners are a hundred feet up). Since the three mile scale is about the upper limit for seeing anything useful on the teeny little radar screens on a yacht, a little heel shouldn't be that much of a problem to justify shelling out the green for a gimbal.

To the original question: In the yacht-size radar department, I've only used a couple Furuno's, which I didn't like since I found them gimicky and non-intuitive. My advice: Simple is good.

Jeff

[ 01-14-2004, 12:13 AM: Message edited by: JeffH ]

Ian McColgin
01-14-2004, 08:26 AM
Though they claim it's safe, I've never really liked when you see the raydome right ahead and gonad level of the flybridge. But maybe someone is trying to improve the gene pool.

The beam is fairly flat and normally the dome is at least a little above head level. That's safe.

I have a buddy who was in the navy for his twenty. He claims that the old radars for targeting, where you could control the sweep and aim at something, were great fun. They'd practice igniting seagulls. If they were running past Revere late at night, they'd sweep the houses along the beach to see how many flourescent kitchen lights they could start up.

But it was an inefficient way to warm a cup of coffee.

Ian McColgin
01-14-2004, 08:26 AM
Though they claim it's safe, I've never really liked when you see the raydome right ahead and gonad level of the flybridge. But maybe someone is trying to improve the gene pool.

The beam is fairly flat and normally the dome is at least a little above head level. That's safe.

I have a buddy who was in the navy for his twenty. He claims that the old radars for targeting, where you could control the sweep and aim at something, were great fun. They'd practice igniting seagulls. If they were running past Revere late at night, they'd sweep the houses along the beach to see how many flourescent kitchen lights they could start up.

But it was an inefficient way to warm a cup of coffee.

Ian McColgin
01-14-2004, 08:26 AM
Though they claim it's safe, I've never really liked when you see the raydome right ahead and gonad level of the flybridge. But maybe someone is trying to improve the gene pool.

The beam is fairly flat and normally the dome is at least a little above head level. That's safe.

I have a buddy who was in the navy for his twenty. He claims that the old radars for targeting, where you could control the sweep and aim at something, were great fun. They'd practice igniting seagulls. If they were running past Revere late at night, they'd sweep the houses along the beach to see how many flourescent kitchen lights they could start up.

But it was an inefficient way to warm a cup of coffee.

Scott Rosen
01-15-2004, 03:13 PM
I spoke with Connecticut Marine Instruments about small radar units. They sell all of the brands and probably do more installations than anyone else around here. They said that the best small LCD unit is, by a long shot, the Raymarine SL-72. The guy I spoke with said that thatís the unit he would install on his boat.

Scott Rosen
01-15-2004, 03:13 PM
I spoke with Connecticut Marine Instruments about small radar units. They sell all of the brands and probably do more installations than anyone else around here. They said that the best small LCD unit is, by a long shot, the Raymarine SL-72. The guy I spoke with said that thatís the unit he would install on his boat.

Scott Rosen
01-15-2004, 03:13 PM
I spoke with Connecticut Marine Instruments about small radar units. They sell all of the brands and probably do more installations than anyone else around here. They said that the best small LCD unit is, by a long shot, the Raymarine SL-72. The guy I spoke with said that thatís the unit he would install on his boat.

Gerald
01-16-2004, 06:04 PM
The Raymarine SL 72 is the unit I would like to purchase. We have two things to watch out for that I am told such units will not pick up? We have fish net markers that are made from big chunks of Styrofoam, a 2 meter pole and a couple of one foot square black flags. The second are 20' wooden fishing boats that no point of the boat sticks more than a meter out of the water. Is it correct that an SL 72 would not pick up the markers or the boats?
Gerald

Gerald
01-16-2004, 06:04 PM
The Raymarine SL 72 is the unit I would like to purchase. We have two things to watch out for that I am told such units will not pick up? We have fish net markers that are made from big chunks of Styrofoam, a 2 meter pole and a couple of one foot square black flags. The second are 20' wooden fishing boats that no point of the boat sticks more than a meter out of the water. Is it correct that an SL 72 would not pick up the markers or the boats?
Gerald

Gerald
01-16-2004, 06:04 PM
The Raymarine SL 72 is the unit I would like to purchase. We have two things to watch out for that I am told such units will not pick up? We have fish net markers that are made from big chunks of Styrofoam, a 2 meter pole and a couple of one foot square black flags. The second are 20' wooden fishing boats that no point of the boat sticks more than a meter out of the water. Is it correct that an SL 72 would not pick up the markers or the boats?
Gerald

Dan McCosh
01-16-2004, 06:14 PM
Out of curiousity, why would the height affect the performance, related to heel angle? The angle would be same regardless of height. Do you mean the effect of rolling or pitching, where the arc would be longer?

Dan McCosh
01-16-2004, 06:14 PM
Out of curiousity, why would the height affect the performance, related to heel angle? The angle would be same regardless of height. Do you mean the effect of rolling or pitching, where the arc would be longer?

Dan McCosh
01-16-2004, 06:14 PM
Out of curiousity, why would the height affect the performance, related to heel angle? The angle would be same regardless of height. Do you mean the effect of rolling or pitching, where the arc would be longer?

JeffH
01-18-2004, 12:45 AM
Originally posted by Gerald:
The Raymarine SL 72 is the unit I would like to purchase. We have two things to watch out for that I am told such units will not pick up? We have fish net markers that are made from big chunks of Styrofoam, a 2 meter pole and a couple of one foot square black flags. The second are 20' wooden fishing boats that no point of the boat sticks more than a meter out of the water. Is it correct that an SL 72 would not pick up the markers or the boats?
GeraldCorrect. Not only will a SL 72 not pick them up, no radar will. Radar, of course, depends on a signal being reflected back to the antenna to detect an object. Round objects and those not made of metal are poor radar reflectors, and are thus virtually invisible, electronically speaking.

Jeff
(can't spell)

[ 01-18-2004, 12:47 AM: Message edited by: JeffH ]

JeffH
01-18-2004, 12:45 AM
Originally posted by Gerald:
The Raymarine SL 72 is the unit I would like to purchase. We have two things to watch out for that I am told such units will not pick up? We have fish net markers that are made from big chunks of Styrofoam, a 2 meter pole and a couple of one foot square black flags. The second are 20' wooden fishing boats that no point of the boat sticks more than a meter out of the water. Is it correct that an SL 72 would not pick up the markers or the boats?
GeraldCorrect. Not only will a SL 72 not pick them up, no radar will. Radar, of course, depends on a signal being reflected back to the antenna to detect an object. Round objects and those not made of metal are poor radar reflectors, and are thus virtually invisible, electronically speaking.

Jeff
(can't spell)

[ 01-18-2004, 12:47 AM: Message edited by: JeffH ]

JeffH
01-18-2004, 12:45 AM
Originally posted by Gerald:
The Raymarine SL 72 is the unit I would like to purchase. We have two things to watch out for that I am told such units will not pick up? We have fish net markers that are made from big chunks of Styrofoam, a 2 meter pole and a couple of one foot square black flags. The second are 20' wooden fishing boats that no point of the boat sticks more than a meter out of the water. Is it correct that an SL 72 would not pick up the markers or the boats?
GeraldCorrect. Not only will a SL 72 not pick them up, no radar will. Radar, of course, depends on a signal being reflected back to the antenna to detect an object. Round objects and those not made of metal are poor radar reflectors, and are thus virtually invisible, electronically speaking.

Jeff
(can't spell)

[ 01-18-2004, 12:47 AM: Message edited by: JeffH ]

Wilson Fitt
01-18-2004, 12:17 PM
I claim no expertise and very little experience with radar. What I do know is that they are definately not all seeing and experienced operators with good gear can miss some pretty important things.

A big Hinkley t-boned an even bigger Swan in the fog in the Bay of Fundy last summer, both with experienced crews and all the gear including radar on and in active use. A friend was aboard the Swan and swears that the Hinkley was invisible on the radar. He also swears that the back of the microwave bears the permanent imprint of a Hinkley bow roller.

Summer before last we were with a small fleet of boats in the Cabot Strait between Cape Breton and Newfoundland, participating in a race to St Pierre. The fleet was accompanied by HMCS Glace Bay, a Canadian Navy coastal defense vessel with, one would presume, the best of gear, well tuned and manned by competant operators. The fleet included a cross section of modern glass boats with aluminum spars, two steel boats (one a 65' schooner) and ourselves, a wooden boat with wooden spars. There were a variety of radar reflectors aloft, probably a good cross section of what's on the market.

The Glace Bay did a poll of all the boats and advised us that no-one were visible to them at more than 5 nm range. They knew we were there, the weather was fine and the seas moderate. So now think about a dirty night, big seas running, lots of rain clutter, and a container ship steaming down on you at 20 knots or more with the bridge watch more focussed on when his shift ends than the radar.

The point of all this is... I'm not sure what, except don't rely entirely on your radar to see what's coming or on the other guy's radar to see you coming. I've been out on those dirty nights trying to suppress my images of the container ship bearing down on us.

[ 01-18-2004, 02:33 PM: Message edited by: Wilson Fitt ]

Wilson Fitt
01-18-2004, 12:17 PM
I claim no expertise and very little experience with radar. What I do know is that they are definately not all seeing and experienced operators with good gear can miss some pretty important things.

A big Hinkley t-boned an even bigger Swan in the fog in the Bay of Fundy last summer, both with experienced crews and all the gear including radar on and in active use. A friend was aboard the Swan and swears that the Hinkley was invisible on the radar. He also swears that the back of the microwave bears the permanent imprint of a Hinkley bow roller.

Summer before last we were with a small fleet of boats in the Cabot Strait between Cape Breton and Newfoundland, participating in a race to St Pierre. The fleet was accompanied by HMCS Glace Bay, a Canadian Navy coastal defense vessel with, one would presume, the best of gear, well tuned and manned by competant operators. The fleet included a cross section of modern glass boats with aluminum spars, two steel boats (one a 65' schooner) and ourselves, a wooden boat with wooden spars. There were a variety of radar reflectors aloft, probably a good cross section of what's on the market.

The Glace Bay did a poll of all the boats and advised us that no-one were visible to them at more than 5 nm range. They knew we were there, the weather was fine and the seas moderate. So now think about a dirty night, big seas running, lots of rain clutter, and a container ship steaming down on you at 20 knots or more with the bridge watch more focussed on when his shift ends than the radar.

The point of all this is... I'm not sure what, except don't rely entirely on your radar to see what's coming or on the other guy's radar to see you coming. I've been out on those dirty nights trying to suppress my images of the container ship bearing down on us.

[ 01-18-2004, 02:33 PM: Message edited by: Wilson Fitt ]

Wilson Fitt
01-18-2004, 12:17 PM
I claim no expertise and very little experience with radar. What I do know is that they are definately not all seeing and experienced operators with good gear can miss some pretty important things.

A big Hinkley t-boned an even bigger Swan in the fog in the Bay of Fundy last summer, both with experienced crews and all the gear including radar on and in active use. A friend was aboard the Swan and swears that the Hinkley was invisible on the radar. He also swears that the back of the microwave bears the permanent imprint of a Hinkley bow roller.

Summer before last we were with a small fleet of boats in the Cabot Strait between Cape Breton and Newfoundland, participating in a race to St Pierre. The fleet was accompanied by HMCS Glace Bay, a Canadian Navy coastal defense vessel with, one would presume, the best of gear, well tuned and manned by competant operators. The fleet included a cross section of modern glass boats with aluminum spars, two steel boats (one a 65' schooner) and ourselves, a wooden boat with wooden spars. There were a variety of radar reflectors aloft, probably a good cross section of what's on the market.

The Glace Bay did a poll of all the boats and advised us that no-one were visible to them at more than 5 nm range. They knew we were there, the weather was fine and the seas moderate. So now think about a dirty night, big seas running, lots of rain clutter, and a container ship steaming down on you at 20 knots or more with the bridge watch more focussed on when his shift ends than the radar.

The point of all this is... I'm not sure what, except don't rely entirely on your radar to see what's coming or on the other guy's radar to see you coming. I've been out on those dirty nights trying to suppress my images of the container ship bearing down on us.

[ 01-18-2004, 02:33 PM: Message edited by: Wilson Fitt ]

Paul Scheuer
01-18-2004, 09:39 PM
don't rely entirely on your radar to see what's coming or on the other guy's radar to see you coming. Right on, Wilson. My USN radar days are from the 60's, but I don't think that the basics have changed that much. There were operators that did nothing but watch the screen, and tweak the machine. Once a suspect target was noticed, there was a lot of tracking and verifying. Sorting out any vessel in the sea return is a little like adjusting the radio for squelch. It's a lot to expect from a crew occupied with other things.

Paul Scheuer
01-18-2004, 09:39 PM
don't rely entirely on your radar to see what's coming or on the other guy's radar to see you coming. Right on, Wilson. My USN radar days are from the 60's, but I don't think that the basics have changed that much. There were operators that did nothing but watch the screen, and tweak the machine. Once a suspect target was noticed, there was a lot of tracking and verifying. Sorting out any vessel in the sea return is a little like adjusting the radio for squelch. It's a lot to expect from a crew occupied with other things.

Paul Scheuer
01-18-2004, 09:39 PM
don't rely entirely on your radar to see what's coming or on the other guy's radar to see you coming. Right on, Wilson. My USN radar days are from the 60's, but I don't think that the basics have changed that much. There were operators that did nothing but watch the screen, and tweak the machine. Once a suspect target was noticed, there was a lot of tracking and verifying. Sorting out any vessel in the sea return is a little like adjusting the radio for squelch. It's a lot to expect from a crew occupied with other things.

Bruce Hooke
01-19-2004, 10:30 AM
Originally posted by Wilson Fitt:
A big Hinkley t-boned an even bigger Swan in the fog in the Bay of Fundy last summer, both with experienced crews and all the gear including radar on and in active use. A friend was aboard the Swan and swears that the Hinkley was invisible on the radar. He also swears that the back of the microwave bears the permanent imprint of a Hinkley bow roller.One big question crosses my mind...was EITHER boat sounding the proper signal on their foghorn? I bet they weren't and I bet that if they had been one or the other would have heard and done something about it.

Bruce Hooke
01-19-2004, 10:30 AM
Originally posted by Wilson Fitt:
A big Hinkley t-boned an even bigger Swan in the fog in the Bay of Fundy last summer, both with experienced crews and all the gear including radar on and in active use. A friend was aboard the Swan and swears that the Hinkley was invisible on the radar. He also swears that the back of the microwave bears the permanent imprint of a Hinkley bow roller.One big question crosses my mind...was EITHER boat sounding the proper signal on their foghorn? I bet they weren't and I bet that if they had been one or the other would have heard and done something about it.

Bruce Hooke
01-19-2004, 10:30 AM
Originally posted by Wilson Fitt:
A big Hinkley t-boned an even bigger Swan in the fog in the Bay of Fundy last summer, both with experienced crews and all the gear including radar on and in active use. A friend was aboard the Swan and swears that the Hinkley was invisible on the radar. He also swears that the back of the microwave bears the permanent imprint of a Hinkley bow roller.One big question crosses my mind...was EITHER boat sounding the proper signal on their foghorn? I bet they weren't and I bet that if they had been one or the other would have heard and done something about it.

Gerald
01-19-2004, 10:44 AM
Thought it only fair to ask the manufacturer. The following is my question and their answer:

Customer (Gerald Niffenegger) 01/17/2004 08:19 AM
The fishermen along our coast use wooden boats in the 20' - 25' range. The highest point above water line would be around one meter. They also use a two meter pole attached to a large block of Styrofoam and a couple of one foot square black flags attached to the top of the pole as net markers. Will the radar unit pick up these boats and markers?
Gerald Niffenegger
Florianopolis, SC Brazil

Response (Raymarine On-Line Support) 01/19/2004 09:29 AM
We do have radars that will pick them up as targets. I would recommend the 4kw dome be used because it has better resolution than 2kw dome

Gerald
01-19-2004, 10:44 AM
Thought it only fair to ask the manufacturer. The following is my question and their answer:

Customer (Gerald Niffenegger) 01/17/2004 08:19 AM
The fishermen along our coast use wooden boats in the 20' - 25' range. The highest point above water line would be around one meter. They also use a two meter pole attached to a large block of Styrofoam and a couple of one foot square black flags attached to the top of the pole as net markers. Will the radar unit pick up these boats and markers?
Gerald Niffenegger
Florianopolis, SC Brazil

Response (Raymarine On-Line Support) 01/19/2004 09:29 AM
We do have radars that will pick them up as targets. I would recommend the 4kw dome be used because it has better resolution than 2kw dome

Gerald
01-19-2004, 10:44 AM
Thought it only fair to ask the manufacturer. The following is my question and their answer:

Customer (Gerald Niffenegger) 01/17/2004 08:19 AM
The fishermen along our coast use wooden boats in the 20' - 25' range. The highest point above water line would be around one meter. They also use a two meter pole attached to a large block of Styrofoam and a couple of one foot square black flags attached to the top of the pole as net markers. Will the radar unit pick up these boats and markers?
Gerald Niffenegger
Florianopolis, SC Brazil

Response (Raymarine On-Line Support) 01/19/2004 09:29 AM
We do have radars that will pick them up as targets. I would recommend the 4kw dome be used because it has better resolution than 2kw dome

TimScearce
01-22-2004, 02:05 PM
Hi All,

I have a Raymarine RL72 radar mounted on my mizzen mast. The radome was mounted by a shipwright in Port Townsend who felt that the 3X5 spruce mast would not support the standard Edson mount I purchased. He came up with the mount shown in the picture. Function won over aesthetics but it has held up nicely to 30kt willawas of Victoria Harbour so I guess I am happy.

The radome is about 12-14' off the water. I can pick out bouys and other small objects without a problem. I have had no problems with accuracy when the boat is over on her rail (where she likes to be).

I installed the 7" monitor under my dodger but found that with tiller steering I have a hard time seeing the screen clearly from anything but a straight on view. I found a color unit with chartplotter and moved the B/W unit inside the cabin. The color is much much easier to read. I also highly recommend the chartplotter/radar combo as you can overlay radar images on top of the chart images. I was able to navigate through the very narrow Swinnomish Channel through Padilla Bay in pitch black using this and am here to tell the tale. (Why I was doing such a dumb thing is another tale for another day).

http://www.fototime.com/CD17A22ED131186/standard.jpg

TimScearce
01-22-2004, 02:05 PM
Hi All,

I have a Raymarine RL72 radar mounted on my mizzen mast. The radome was mounted by a shipwright in Port Townsend who felt that the 3X5 spruce mast would not support the standard Edson mount I purchased. He came up with the mount shown in the picture. Function won over aesthetics but it has held up nicely to 30kt willawas of Victoria Harbour so I guess I am happy.

The radome is about 12-14' off the water. I can pick out bouys and other small objects without a problem. I have had no problems with accuracy when the boat is over on her rail (where she likes to be).

I installed the 7" monitor under my dodger but found that with tiller steering I have a hard time seeing the screen clearly from anything but a straight on view. I found a color unit with chartplotter and moved the B/W unit inside the cabin. The color is much much easier to read. I also highly recommend the chartplotter/radar combo as you can overlay radar images on top of the chart images. I was able to navigate through the very narrow Swinnomish Channel through Padilla Bay in pitch black using this and am here to tell the tale. (Why I was doing such a dumb thing is another tale for another day).

http://www.fototime.com/CD17A22ED131186/standard.jpg

TimScearce
01-22-2004, 02:05 PM
Hi All,

I have a Raymarine RL72 radar mounted on my mizzen mast. The radome was mounted by a shipwright in Port Townsend who felt that the 3X5 spruce mast would not support the standard Edson mount I purchased. He came up with the mount shown in the picture. Function won over aesthetics but it has held up nicely to 30kt willawas of Victoria Harbour so I guess I am happy.

The radome is about 12-14' off the water. I can pick out bouys and other small objects without a problem. I have had no problems with accuracy when the boat is over on her rail (where she likes to be).

I installed the 7" monitor under my dodger but found that with tiller steering I have a hard time seeing the screen clearly from anything but a straight on view. I found a color unit with chartplotter and moved the B/W unit inside the cabin. The color is much much easier to read. I also highly recommend the chartplotter/radar combo as you can overlay radar images on top of the chart images. I was able to navigate through the very narrow Swinnomish Channel through Padilla Bay in pitch black using this and am here to tell the tale. (Why I was doing such a dumb thing is another tale for another day).

http://www.fototime.com/CD17A22ED131186/standard.jpg

ErikH
01-25-2004, 10:45 PM
We owned a Furuno 1821.
You didn't say (maybe everyone just knows) what you'll be doing with it, and that makes quite a bi of difference in advice.
We used ours extensively for coastal and ocean sailing. We found it invaluable at night and in iffy weather conditions, as well as for things like sailing in January (there's nobody out there at night, and it is MUCH nicer to watch the radar and do a visual scan every 3-5 minutes than to stay on deck the whole time). We've entered harbors at night, left harbors in the morning, gone through Watch hill Passage in pea soup fog at night... it's a great thing, radar is.

I really can't overemphasize the importance of a good screen. If you plan to echo a lot of stuff to your radar (GPS, depth, etc etc) or if you want the ability to split screen, or to do all of that other quasi-computerized stuf that radars will do (much of which is incredibly handy once you get to know it well) you will find that screen size and resolution are pretty darn important. At the time we purchased ours, the Furuno had an extra inch of diagonal screen size, and four times the resolution, of the Raytheons. Which is why it cost more, of course. But the text, and everything else, was more readable (in our view), it worked like a dream, and we never regretted the purchase.
I had the radar inside at the nav table but could see it from the cockpit (that large clear screen again) so it was the best of both worlds.

We had ours mounted probably about 25' up. Every radar has a horizontal and vertical beam width; if you use the vertical width divided by two and calculate the angles (simple trig) you can find where a theoretical height will 'stop seeing' as you come closer to the boat.

For offshore use you don't want it too low (sea clutter is more of a problem, or waves getting in the way). We never had an issue with failing to see something; there's always a bit of radar scatter and if something important (a buoy, say) is a bit inside the circle they have good returns and you can see them anyway.

you REALLY don't want to get hit by it if you can avoid it; it damages the retina (or was it the cornea) and unless you're the type not to wear safety goggles when you grind steel, that's not a risk I'd advise. Again, the vertical beam width allows you to calculate that well.

Our boat was one of the rolliest ones in existence, i think. We did not have a gimballed mount and rarely had a problem. Look at it this way: if it's windy enough for you to be heeled over 30 degrees, it's wavy (or gusty) enough most of the time that you roll enough to scan the whole horizon anyway, with any of the radars you discussed.

I don't recognize the Furuno you mentioned but I think it might be the mini unit with a 6" screen which IMO is enough right away to discard it (just too darn small). the raytheon is in wide use and umimpeachable for the price. if you can afford the $$ (and the slightly increased display size) the nicer Furunos are well worth owning. the more you plan to use it, of course, the more you might spend. If you can afford an add-on, consider a fluxgate compass, which will allow north-up stabilized display. I always wished I had it.

ErikH
01-25-2004, 10:45 PM
We owned a Furuno 1821.
You didn't say (maybe everyone just knows) what you'll be doing with it, and that makes quite a bi of difference in advice.
We used ours extensively for coastal and ocean sailing. We found it invaluable at night and in iffy weather conditions, as well as for things like sailing in January (there's nobody out there at night, and it is MUCH nicer to watch the radar and do a visual scan every 3-5 minutes than to stay on deck the whole time). We've entered harbors at night, left harbors in the morning, gone through Watch hill Passage in pea soup fog at night... it's a great thing, radar is.

I really can't overemphasize the importance of a good screen. If you plan to echo a lot of stuff to your radar (GPS, depth, etc etc) or if you want the ability to split screen, or to do all of that other quasi-computerized stuf that radars will do (much of which is incredibly handy once you get to know it well) you will find that screen size and resolution are pretty darn important. At the time we purchased ours, the Furuno had an extra inch of diagonal screen size, and four times the resolution, of the Raytheons. Which is why it cost more, of course. But the text, and everything else, was more readable (in our view), it worked like a dream, and we never regretted the purchase.
I had the radar inside at the nav table but could see it from the cockpit (that large clear screen again) so it was the best of both worlds.

We had ours mounted probably about 25' up. Every radar has a horizontal and vertical beam width; if you use the vertical width divided by two and calculate the angles (simple trig) you can find where a theoretical height will 'stop seeing' as you come closer to the boat.

For offshore use you don't want it too low (sea clutter is more of a problem, or waves getting in the way). We never had an issue with failing to see something; there's always a bit of radar scatter and if something important (a buoy, say) is a bit inside the circle they have good returns and you can see them anyway.

you REALLY don't want to get hit by it if you can avoid it; it damages the retina (or was it the cornea) and unless you're the type not to wear safety goggles when you grind steel, that's not a risk I'd advise. Again, the vertical beam width allows you to calculate that well.

Our boat was one of the rolliest ones in existence, i think. We did not have a gimballed mount and rarely had a problem. Look at it this way: if it's windy enough for you to be heeled over 30 degrees, it's wavy (or gusty) enough most of the time that you roll enough to scan the whole horizon anyway, with any of the radars you discussed.

I don't recognize the Furuno you mentioned but I think it might be the mini unit with a 6" screen which IMO is enough right away to discard it (just too darn small). the raytheon is in wide use and umimpeachable for the price. if you can afford the $$ (and the slightly increased display size) the nicer Furunos are well worth owning. the more you plan to use it, of course, the more you might spend. If you can afford an add-on, consider a fluxgate compass, which will allow north-up stabilized display. I always wished I had it.

ErikH
01-25-2004, 10:45 PM
We owned a Furuno 1821.
You didn't say (maybe everyone just knows) what you'll be doing with it, and that makes quite a bi of difference in advice.
We used ours extensively for coastal and ocean sailing. We found it invaluable at night and in iffy weather conditions, as well as for things like sailing in January (there's nobody out there at night, and it is MUCH nicer to watch the radar and do a visual scan every 3-5 minutes than to stay on deck the whole time). We've entered harbors at night, left harbors in the morning, gone through Watch hill Passage in pea soup fog at night... it's a great thing, radar is.

I really can't overemphasize the importance of a good screen. If you plan to echo a lot of stuff to your radar (GPS, depth, etc etc) or if you want the ability to split screen, or to do all of that other quasi-computerized stuf that radars will do (much of which is incredibly handy once you get to know it well) you will find that screen size and resolution are pretty darn important. At the time we purchased ours, the Furuno had an extra inch of diagonal screen size, and four times the resolution, of the Raytheons. Which is why it cost more, of course. But the text, and everything else, was more readable (in our view), it worked like a dream, and we never regretted the purchase.
I had the radar inside at the nav table but could see it from the cockpit (that large clear screen again) so it was the best of both worlds.

We had ours mounted probably about 25' up. Every radar has a horizontal and vertical beam width; if you use the vertical width divided by two and calculate the angles (simple trig) you can find where a theoretical height will 'stop seeing' as you come closer to the boat.

For offshore use you don't want it too low (sea clutter is more of a problem, or waves getting in the way). We never had an issue with failing to see something; there's always a bit of radar scatter and if something important (a buoy, say) is a bit inside the circle they have good returns and you can see them anyway.

you REALLY don't want to get hit by it if you can avoid it; it damages the retina (or was it the cornea) and unless you're the type not to wear safety goggles when you grind steel, that's not a risk I'd advise. Again, the vertical beam width allows you to calculate that well.

Our boat was one of the rolliest ones in existence, i think. We did not have a gimballed mount and rarely had a problem. Look at it this way: if it's windy enough for you to be heeled over 30 degrees, it's wavy (or gusty) enough most of the time that you roll enough to scan the whole horizon anyway, with any of the radars you discussed.

I don't recognize the Furuno you mentioned but I think it might be the mini unit with a 6" screen which IMO is enough right away to discard it (just too darn small). the raytheon is in wide use and umimpeachable for the price. if you can afford the $$ (and the slightly increased display size) the nicer Furunos are well worth owning. the more you plan to use it, of course, the more you might spend. If you can afford an add-on, consider a fluxgate compass, which will allow north-up stabilized display. I always wished I had it.