Nice little radar for NEAR objects, where it counts. Mount it LOW down, not way up high trying to see targets 16 miles away. If it's 12' off the deck, it'll show you that bouy in the fog nearly right up until you run over it! Way up high, it'll overshoot the bouy at the worst time....when you're close!
If you go to http://www.jrcamerica.com, and look for "light marine/Radar, you will find the Radar 1000 Mk II listed, and the manual is available there for download. Don't know if that will be the exact manual for your unit, but it may be close enough - otherwise you could email them for information.
Larry, That is an astute observation. In fact, in the Netherlands, a regulation was recently passed that all the commercial shipping must have radars that work between 0 and 100 meters by the end of '06. This will be a big problem because most of the existing commercial radars and their mounting will not see close targets. However, the vertical fan of most antennas is 30 degrees, so mounting isn't the biggest problem. The biggest issue is pulse width and electronics speed. At 6.36usec per radar mile, the pulse width must be less than 1usec and the receiver must be on within nano seconds after the pulse transmission in order to sense a close target. Steve
"Larry W4CSC" <noone@home.com> wrote in message news:Xns9626CF909B12Fw4csc@63.223.7.253...> "david" <lynez@optusnet.com.au> wrote in> news:42474ce5$0$5599$afc38c87@news.optusnet.com.au:>
Can anyone help I bought the radar second hand and I don't know how to>> use it>> has anyone got a manual in pdf format please>> David in perth>>
Nice little radar for NEAR objects, where it counts. Mount it LOW down,> not way up high trying to see targets 16 miles away. If it's 12' off the> deck, it'll show you that bouy in the fog nearly right up until you run> over it! Way up high, it'll overshoot the bouy at the worst time....when> you're close!>
"Steve Lusardi" <stevenospam@lusardi.de> wrote in news:d28f3e$q24$04$1@news.t-online.com:
At 6.36usec per radar mile, the pulse width must be less > than 1usec and the receiver must be on within nano seconds after the> pulse transmission in order to sense a close target.> Steve>
The little 2KW Raymarine can see the docks three slips away from about 22' up Lionheart's mizzen. It draws so little DC power its pulse width has to be very narrow, indeed. I know of someone else who regrets putting the radar atop the mast at 55' on a sloop because the bouys disappear about a football field length away from the boat with the same radar.
This observation of the Raymarine 2KW is taken when the radar is new, not after the internal condensation problems of Raymarine radomes has eaten away the potmetal chassis, rendering it useless. I just put the third radome up the mizzen.
By the way, for the Raymarine 2KW owners, the new radome has these little plastic feet to hold the radome up off the mounting by about 1/2 inch. The mounting bolts go through a hole in these feet. Looks like a patch for the problem of stainless steel bolts and pot metal holes they screw into making another galvanic battery to eat the chassis off from the bottom.
On Mon, 28 Mar 2005 05:12:28 -0500, Larry W4CSC <noone@home.com> wrote:
This observation of the Raymarine 2KW is taken when the radar is new, not >after the internal condensation problems of Raymarine radomes has eaten >away the potmetal chassis, rendering it useless. I just put the third >radome up the mizzen.
I know you don't like this particular pot metal assembly, but why are you on your third rather than switch to another brand?
On Sun, 27 Mar 2005 20:21:30 -0500, Larry W4CSC <noone@home.com> wrote:
Nice little radar for NEAR objects, where it counts. Mount it LOW down, >not way up high trying to see targets 16 miles away. If it's 12' off the >deck, it'll show you that bouy in the fog nearly right up until you run >over it! Way up high, it'll overshoot the bouy at the worst time....when >you're close!>
I have a JRC 1000. I use it the most for anchiring. It shows the other boats in the anchorage down to less then 1/16 of a mile. You can make sure there is a couple of hundred feet all around very easily.
On Mon, 28 Mar 2005 05:12:28 -0500, Larry W4CSC <noone@home.com> wrote:
By the way, for the Raymarine 2KW owners, the new radome has these little >plastic feet to hold the radome up off the mounting by about 1/2 inch. The >mounting bolts go through a hole in these feet. Looks like a patch for the >problem of stainless steel bolts and pot metal holes they screw into making >another galvanic battery to eat the chassis off from the bottom.
Larry, Do you think threaded nylon stand-offs with 1/4-20 nylon bolts solve the problem? Norm B
engsol <engsolnorm@peak.org> wrote in news:5d6h419m7hsr679jo99jqpfb9bap9574uk@4ax.com:
Larry,> Do you think threaded nylon stand-offs with 1/4-20 nylon bolts > solve the problem?> Norm B>
Not at all. The condensation problems stem from the dome being open to the air and exposed to the sun in a high humidity environment. It works the same as a nearly-empty gas tank sucking in cold, wet night air when the sun sets to condense inside all night and run down the walls, then blow air out the little rubber tit at the bottom of the radome when the sun comes up, boiling off what water it can in the heat of the day to create its own rainstorm inside the OPEN pot metal chassis to eat away at the electronics until the sun sets, again, to repeat the process.
The problem is not the bottom mounting, the problem is the "gas tank effect" creating saturated hot air inside the dome because it's cheap to make an unsealed dome that doesn't have to withstand a few pounds of pressure......
Some of the older Raymarine radars used the same internals as JRC, but I have not seen a cross reference for model numbers, just parts. Raymarine does have several of their older manuals available for download from their web site, so if there is an equivalent, and you can find out what it is, you might find some help there.
"david" <lynez@optusnet.com.au> wrote in message news:42474ce5$0$5599$afc38c87@news.optusnet.com.au...> Can anyone help I bought the radar second hand and I don't know how to use> it> has anyone got a manual in pdf format please> David in perth>
Thankyou all for your help and advice a kind reader has sent me the manual and I will mount it low as suggested. it was good to see no negative comments about the JRC1000. David
"david" <lynez@optusnet.com.au> wrote in message news:4249b472$0$7840$afc38c87@news.optusnet.com.au...> Thankyou all for your help and advice a kind reader has sent me the manual> and I will mount it low as suggested.> it was good to see no negative comments about the JRC1000.> David> Several people have complained about the noise that the smaller JRC, Furuno, etc., radars make when mounted directly on top of a thin fiberglass or metal cabin roof. The roof/overhead tends to act as a acoustic diaphragm, making the cabin noisy from drive motor/gear operation. The quick fix in most cases is a very small amount of grease on the motor gear/ring gear teeth. Some motors are shock mounted in rubber grommets, and permit loosening the mounting bolt and tiny adjustment of the motor position can be done, changing the depth of the gear teeth mesh, until a quiet point is found. Possibly remounting the scanner dome on rubber or plastic washers would reduce the noise also. Raymarine tends to use belt drive, so drive noise is usually not a problem. 73 Doug K7ABX
