JRC 1000 Radar Questions

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TheBoatman

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A friend of mine has a fishing boat with a JRC 1000 radar on and he asked me to set it up for him, despite my reading the manual several times over and doing what was asked I am still not getting a decent radar picture.

Has anyone any useful tips?

The problems I'm having is that shore lines are very broken and targets are not in the postion reletive to the ships heading.

Any help would be much appreciated.

Peter.


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Switch to heads up instead of North up, and get some training <g> Shore lines will always be broken, that's a given

<hr width=100% size=1>Me transmitte sursum, caledoni
 
Is there a connectr in the cable between scanner and display - sounds like the connection is not very good, and is allowing noise in.

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YM write up in 2002, gave poor display due to small scanner, short range and fuzzy coast.
May be radar not you.


Brian

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We fitted a small radar system this year and were initially dissappointed by the display. This was expectation rather than poor performance. In the Channel where there is less clutter, other vessels are easily identified and tracked. This level of performance, especially in fog, is after all why we bought just about the cheapest unit available. Don't expect to see crisp outlines that are sufficiently accurate to navigate by. To get that, you must spend loads.

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There are obviously limitations with inexpensive radars and small scanners but the prime thing IMO is that targets MUST appear on the right heading. Heading is normally adjustable, crudely by turning the scanner on it's mounts and fine tuned (on most models) by adjustment electronically in the display head, usually this adjustment is 'hidden' being intended for the dealer rather than the user but the handbook should say. If you cannot adjust it so that a known target seen visually on the nose is also on the nose on the radar, that set cannot be safely used for collision avoidance, Shorelines are not clear solid lines unless they are very good radar targets, like a solid harbour wall or vertical rock cliff. Usually what happens is that with a wide beamwidth from a small scanner the shore ends up merging into a solid blob when you are close and appears as isolataed blobs when far away. they NEVER look like the demo pics in the brochures, unless perhaps you have a really expensive set with a big scanner.

With apologies if this is teaching Granny to suck eggs.

<hr width=100% size=1><font size=1>Sermons from my pulpit are with tongue firmly in cheek and come with no warranty!</font size=1>
 
Have you performed the "Operating Initial Settings"?

For Target Bearing:-
Follow the instructions for "Relative Bearing Alignment" on page 17.
1. Identify a suitable target preferably between 0.5 and 1.0 NM.
2. Visually line the bow of the vessel up with the taget.
3. Pur the EBL marker on the target.
4. Press and hold the JOYSTICK for the initail setting menu.
5. Select BEARING by using the JOYSTICK, press the JOYSTICK for the bearing adjustment mode.
6. Put the EBL over the target. using the JOYSTICK
7. Move the EBL so that the target will be displayed on the SHM (Ships Heading Marker).
8. Press the JOYSTCK to end the bearing adjustment mode.

Then perform the "Display Timing (Zero NM Adjustment)", followed by "Tune Preset", "STC Preset", etc.

Hope this helps,



<hr width=100% size=1>Brian
http://homepage.ntlworld.com/brunyard
 
<targets are not in the position relative to the ships heading>
As Robin says, you have to twist the head, then do the electronic tweak. I found that the electronic tweak moved the image in steps, so to get it exact, I found it necessary to then readjust the head a smidgen.


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The jinglish instructions are pretty awful - if you know someone that can read german, the german ones explain the set up procedure better.

Is it connected to a GPS - if so the ships head is taken as COG and the bearings are measured as though relative to this.

If the targets are not where the radar says they are when you look out the window the radar needs realigning -if memory serves me correctly you point at target with bows, enter initial set up, move ebl over target (using jog dial) then press joy stick - move ebl to to Head up marker(using jog dial) and press joysick again and magically target moves itself onto ships head (or not....)

send me a PM if you want any further info



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Thanks everyone for the info and help.

I think I'm going to have to go back to the begining and try setting it up again because whilst I didn't explain it very well in my first post I do have "some targets" on screen but not all. Last Friday we fished out of Ramsgate but went down towards Dover this took us past Deal and all the relevant bouys in the Gull Ch. I could just make out the shore line but Deal pier wasn't shown neither were any of the bouys. A large ship sitting in Deal Roads showed as a small blip but not in relation to ships heading. We finally ended up a couple of miles from Dover and none of the cross ch ferries showed at all.

Will it be possible to make an initial set up inside Ramsgate harbour complete with all the clutter of harbour walls and boats or is it best to try setting the unit up outside of the harbour?

Peter.

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You can do an initial set up inside the harbour but that is all. The 'gain' control needs to be set so that the screen JUST speckles, in harbour however this gain setting will probably result in a mass of blobs merging together from too many close targets. Similarly with the 'tune' control, again best set outside the harbour to give the best pic of weak target - if the set has an autotune feature use it. Tuning will need readjustment as the set warms up too. Some sets have automatic controls for 'gain', 'seaclutter' and 'rain'. On our Raytheon the autogain sets it too high and this affects any 'trail' or target plot feature so I don't use it, but I do use the 'auto' settings for rain and seaclutter.

Did you try turning up the gain and adjusting the tuning when on your trip? Bouys are not necessarily good radar targets unless they have reflectors fitted, starboard buoys almost have a 'stealth' profile unless made of crossed plates like a motoring cone. A wooden pier should show if seen ahead, if seen from abeam it won't be clear as it is just a bump in the range in effect of the general shoreline. The size of a ship isn't relevant to it's size on the screen really, targets farther away show larger than the same size target closer to, that is a function of the beam width (I could show you with a diagram but it is difficult to describe!). The range at which you pick up ships, irrespective of their size in terms of length at least depends on the height of the scanner, the height of the target and the aspect of the target. radar sees vertical walls well and sloping ones less well (the return bounces up and away), so the side of a ship is a good target. Bows on the hull is a) smaller target and b) not vertical except say for the bridge so a poorer target. You should certainly expect to pick up big ships at 6mls and this is a good range to watch on initially, switching to closer ranges as needed. On a small radar, yachts with reflectors will show intermittently (very) at say 4mls and not continuously until say 2mls away, buoys will not show anywhere near as well as that.

The one thing you MUST get right is the bearing at which a target shows. You need to set it up roughly in harbour by moving the scanner on it's mount, then find a small clear taget somewhere dead ahead and adjust the fine tuning for heading on the set itself so that this target shows dead ahead on the screen as well. This setting is essential for collision avoidance, if this is wrong you cannot plot anything in terms of collision avoidance with any confidence at all and that is the prime reason for installing radar.

Good luck, best thing is to get out and play with it in GOOD visibilty so you can see visually what the screen shows.

<hr width=100% size=1><font size=1>Sermons from my pulpit are with tongue firmly in cheek and come with no warranty!</font size=1>
 
I messed around with teh settings on my 1500 (Mk1) for some time until I had the heading bang on - you have significant adjustmnet in setup so dont bother with moving the mount (unless someones mounted it a 90 degrees!). You have to follow the steps precisely however there are 2 distinct element to set up - the heading and the screen tuning. The former can be done over and over again until you are happy with it in action but the sceen needs to be done first otherwise you wont have anything to compare the heading with clearly. I would anchor half a mile off the breakwater for the initial setup which should be perfect for all the settings.
One final point I find that I have to adjust the gain if I reset the range to give me the clearest picture whilst leaving the autotune to do it's work. As I have said elsewhere having both these items on the one button menu isn't ideal!

<hr width=100% size=1>madesco madidum ..../forums/images/icons/smile.gif
 
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