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#1
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Jim Thompson wrote:
I bought radar before this past season for the first time. Real "eye opener". Found it very useful, even in clear weather -- we only get fog 4 day/month in the Northumbeland Strait. If I was venturing out on a longer range trip I would not be without GPS, sounder and radar. We have a radar set on the tugboat. A bit old, and doubtfully installed by DPO, but it seemed capable of working. The return was very garbled and unclear, it would not even pick up large buildings on shore from more than 1/2 mile away. I was convinced that we should buy a new one, but going through the tuning & timing procedure in the owners manual (at least the DPO saved them) improved the return picture a LOT. Over the past year I've tweaked the thing a little here and there, as time & opportunity came along, and after some coaching by a retired Navy OS Master Chief, we get a great return picture out to about 16 miles. It will pick up a floating soda can in calm water, show rain squals, outline marshy shore, etc etc. Our radar has proven to be a really good tool for use in marginal visibility and for tracking ship traffic. When we first bought the boat I was not convinced of it's usefulness, especially not that particular set. But now it works great. BTW thanks Jeff for your comments about magnetron life. Fresh Breezes- Doug King |
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#2
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On Tue, 25 Nov 2003 09:50:07 -0500, DSK wrote:
Our radar has proven to be a really good tool for use in marginal visibility and for tracking ship traffic. When we first bought the boat I was not convinced of it's usefulness, especially not that particular set. But now it works great. One last thing I forgot to mention: Here on Lake Ontario many summer storms appear as "pop-up" cumulonimbus thunderheads, with 50-60 knot line squalls that can lay you flat if you have, as most do most of the time, a full hoist... There's only 20-30 miles to the west end of the lake here (Toronto) and squalls that develop at that end (south to west, usually) can get here in minutes. A properly tuned radar will show squall lines quite sharply. If its blasting at you at 48 knots and you catch it on radar aft at 12 NM, you can shorten sail in a timely fashion and ride out an otherwise very unpleasant, possibly expensive and potentially dangerous 15 minute surfing session. And of course, if you can see rain bands, you can sail between them, if the wind and waves allow. R. |
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#3
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On Tue, 25 Nov 2003 09:50:07 -0500, DSK wrote:
Our radar has proven to be a really good tool for use in marginal visibility and for tracking ship traffic. When we first bought the boat I was not convinced of it's usefulness, especially not that particular set. But now it works great. One last thing I forgot to mention: Here on Lake Ontario many summer storms appear as "pop-up" cumulonimbus thunderheads, with 50-60 knot line squalls that can lay you flat if you have, as most do most of the time, a full hoist... There's only 20-30 miles to the west end of the lake here (Toronto) and squalls that develop at that end (south to west, usually) can get here in minutes. A properly tuned radar will show squall lines quite sharply. If its blasting at you at 48 knots and you catch it on radar aft at 12 NM, you can shorten sail in a timely fashion and ride out an otherwise very unpleasant, possibly expensive and potentially dangerous 15 minute surfing session. And of course, if you can see rain bands, you can sail between them, if the wind and waves allow. R. |
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#4
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Jim Thompson wrote:
I bought radar before this past season for the first time. Real "eye opener". Found it very useful, even in clear weather -- we only get fog 4 day/month in the Northumbeland Strait. If I was venturing out on a longer range trip I would not be without GPS, sounder and radar. We have a radar set on the tugboat. A bit old, and doubtfully installed by DPO, but it seemed capable of working. The return was very garbled and unclear, it would not even pick up large buildings on shore from more than 1/2 mile away. I was convinced that we should buy a new one, but going through the tuning & timing procedure in the owners manual (at least the DPO saved them) improved the return picture a LOT. Over the past year I've tweaked the thing a little here and there, as time & opportunity came along, and after some coaching by a retired Navy OS Master Chief, we get a great return picture out to about 16 miles. It will pick up a floating soda can in calm water, show rain squals, outline marshy shore, etc etc. Our radar has proven to be a really good tool for use in marginal visibility and for tracking ship traffic. When we first bought the boat I was not convinced of it's usefulness, especially not that particular set. But now it works great. BTW thanks Jeff for your comments about magnetron life. Fresh Breezes- Doug King |
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#5
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I bought radar before this past season for the first time. Real "eye
opener". Found it very useful, even in clear weather -- we only get fog 4 day/month in the Northumbeland Strait. If I was venturing out on a longer range trip I would not be without GPS, sounder and radar. Jim http://jimthompson.net/boating/ECharting/JRC1500.htm On Sun, 23 Nov 2003 09:07:50 -0800, "Lloyd Sumpter" wrote: Hi, Thinking of getting radar for Far Cove, mainly for this planned trip to WCVI, which has lots of fog. Now, I've survived 20+ years of sailing Georgia Strait, etc. without radar. If it's really foggy, I just stay put. If I venture out, I use several nav aids including GPS to determine my position, blow my horn and listen. I'm thinking that, even WITH radar, I wouldn't venture out in unfamiliar waters in dense fog. And if I was out and the fog rolled in on me, I would think that GPS, sounder and a good chart would be better to find that anchorage than radar, assuming I could see at least 100 ft or so. Comments? |
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#6
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On Sun, 23 Nov 2003 09:07:50 -0800, "Lloyd Sumpter"
wrote: Hi, Thinking of getting radar for Far Cove, mainly for this planned trip to WCVI, which has lots of fog. Now, I've survived 20+ years of sailing Georgia Strait, etc. without radar. If it's really foggy, I just stay put. If I venture out, I use several nav aids including GPS to determine my position, blow my horn and listen. I'm thinking that, even WITH radar, I wouldn't venture out in unfamiliar waters in dense fog. And if I was out and the fog rolled in on me, I would think that GPS, sounder and a good chart would be better to find that anchorage than radar, assuming I could see at least 100 ft or so. Under ideal conditions, you are correct. The benefit of radar, however, is that you can see what you can't hear, i.e. other shipping that has no intention of letting a little fog screw with the schedule... Also, to a lesser extent, you become visible to other shipping in a way that a horn can't: precisely. Finally, you can use a radar to get bearings on shore objects at night if the GPS conks out and it's too cloudy to use celestial...which I notice you didn't mention...G I would say radar, sensibly used, complements but doesn't replace paper, GPS, depth sounders, horns and good old seamanship. While it is possible to get swamped with "too much information", particularly if it doesn't agree, too little information is often what proves fatal to the boat. Comments? Also, if I mount the radome on a post at the stern like most seem to, doesn't the mast and sail interfere with it looking forward? Yes, but barely, or at least not as much as you'd think. You can offset the radome on a pole and gimbal off a stern quarter if you wish, and then the "blind spot" would be 10 deg. port or starboard looking forward. I agree, a gimbal mount at the cross-trees is probably ideal, however, but it's easier to get at stuff on a pole. Probably the nicest option is an arch with the radar offset and a way to lash the boom, hang bimini canvas, affix a GPS, VHF, etc., and yet keep all within easy reach. R. Lloyd Sumpter "Far Cove" Catalina 36 |
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#7
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wrote in message
... ... Also, to a lesser extent, you become visible to other shipping in a way that a horn can't: precisely. This is a point I've wondered about: it seems that vessels with active radar appear on my radar with a large arc centered on the vessel's blip. I've assumed this is an interaction between their radar and mine. Does this also mean that my radar also enhances my picture on their screen? -jeff |
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#8
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On Tue, 25 Nov 2003 21:42:50 -0500, "Jeff Morris"
wrote: wrote in message .. . ... Also, to a lesser extent, you become visible to other shipping in a way that a horn can't: precisely. This is a point I've wondered about: it seems that vessels with active radar appear on my radar with a large arc centered on the vessel's blip. I've assumed this is an interaction between their radar and mine. Does this also mean that my radar also enhances my picture on their screen? -jeff Don't count on it. The arc that you see from the other guys radar is from interference from his transmitter. Your radar is picking up your transmitters echo and his transmitter directly. His pulses are not synchronized with yours so you see the trail of pulses from his transmitter while your transmitter is between pulses. It will give neither of you any indication of where the other is. This only happens if the two transmitters are very close to the same frequency. Even though the two radar's may be exactly the same type of radar, they may or may not be close enough to the same frequency. The magnetrons are all tuned slightly different and drift somewhat. On most radar's there is also an interference filter on the receivers that eliminate or reduce that type of interference. Then too the other ship may be using a radar in a completely different band. No interference to either of you. Regards Gary |
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#9
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Jeff Morris wrote: wrote in message ... ... Also, to a lesser extent, you become visible to other shipping in a way that a horn can't: precisely. This is a point I've wondered about: it seems that vessels with active radar appear on my radar with a large arc centered on the vessel's blip. I've assumed this is an interaction between their radar and mine. Does this also mean that my radar also enhances my picture on their screen? -jeff This may also be due to having the gain/intensity, turned up too high for the given range scale you are using. It can sometimes be countered with the anti clutter controls, alone. |
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#10
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"otnmbrd" wrote in message news:_I4xb.15704
This is a point I've wondered about: it seems that vessels with active radar appear on my radar with a large arc centered on the vessel's blip. I've assumed this is an interaction between their radar and mine. Does this also mean that my radar also enhances my picture on their screen? This may also be due to having the gain/intensity, turned up too high for the given range scale you are using. It can sometimes be countered with the anti clutter controls, alone. Who said I wanted to get rid of it? Its kind of nice have a special identifier for some vessels. How can I enhance it? |
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