Recommendations for Cheap, Older, Basic Radar ?

[Stillraining]

Originally Posted by Hampus

You should excpect no shortcomings from your JRC. There is no reason for saying it's bad. JRC are huge in marine electronics, although 90% of their market is in Asia. Until 1996 Raytheon and JRC were one. If you open a Raytheon manufactured pre 1996 all you see are "JRC"-stanps. Are all Raytheon crap? A lot of other brands use JRC components like magnetrons and micro frontends. I've spent the past 9 years in the marine electronic business, two of those years working for a JRC dealer. I've installed and/or serviced I think most of the big names like JRC, Raytheon, Raymarine, Atlas, Terma, Furuno etc. and none is better than the other. They all have their pros and cons and they're all inovative in their own areas, but saying that JRC makes bad equipment really is unfounded. They might be a bit sluggish when it comes to installation and user friendlieness and they have no clue what the word "design" means, but if you just keep the water out of the equipment, same as the rest, it will keep going and going and do you good for many years.

/Hampus

Thanks Mate...

[Nauticatarcher]

From personal use on a variety of vessels using a range of brands I found the smallest JRC Radar to have the worst target discrimination, maybe it was a bad installation?

[RBEmerson]

How big is "small"? Again, [antenna] size does matter in resolving targets (e.g., separating a tug from a towed barge, a buoy from a boat nearby).

[Hampus]

Originally Posted by Nauticatarcher

From personal use on a variety of vessels using a range of brands I found the smallest JRC Radar to have the worst target discrimination, maybe it was a bad installation?

No, the installation wouldn't have anything to do with it. As previously stated; antenna sizer is what matters when it comes to target resolution, and the JRC-1000 is as small as they come. It is and will always be worse at target discrimination than the bigger models, but IMO it's not worse nor better than the other brands in the same size.

I don't know what has happened to the prices, but when they first appeared on the market, the JRC-1000 and JRC-1500 got their names from their prices, $1000 and $1500. They are both great value for money.

/Hampus

[imagine2frolic]

The rules say one should use every means available to you to navigate. As they see it. If you have radar you should be using it. I use to wonder why I would see large boats on a perfectly clear day with the radar sweeping. Now I know, because they were professional skippers, and just following the rules.

[JRC Support]

Unless you are installing a solid state radar (of which you now have a few choices) you will always be faced with the shortcomings of a tube magnetron. JRC makes a 30Kw S band radar that would cut through any fog you could throw at it, but unfortunately, it would sink your sailboat from sheer weight.

The R100 and 1500 series radars were 1kW and 1.5kW respectively. As such, they don’t puke out a lot of power. However, mag output power is not the only thing to consider when talking about short range performance. Tuning, the quality of the front end and cable length as associated to timing are all factors.

Here are some tech notes for these radar units that you guys might find handy:

Common Problems of Radar 1000/1500/1000MkII/1500MkII


Poor sensitivity – can only see targets out to a maximum of ¾ or 1.5 miles range
Most units have no problem from the factory, however some require adjustment as described in the initial settings page of the owners manual. In particular the Tuning Preset and STC Preset will greatly affect target presentation. The tuning preset is a coarse tune and will cause the auto tune function to work intermittently or not at all if misadjusted. The STC Preset can cause close in targets to disappear if misadjusted.

Picture cut in half with bottom of screen showing on the top half of the screen. – Internal CPU glitch
usually caused by power line sag or spike (possibly by engine starting). This requires a reset. First try a soft reset (hold in EBL/VRM button while turning on the radar). If this doesn’t work, try a master reset (hold in Offset and Dim/Cont buttons while turning on radar). This will reset everything and all the Initial Menu settings will need to be redone. Resets return the start up screen hour meter back to 0H (0000 hours)

Foggy screen – Serial numbers less than LT25031 require anti-fogging gasket to be installed.
A few radar displays have developed condensation on the inside of the plastic window under certain temperature/humidity conditions, which combined with the air space inside allows it to act as a small cloud
chamber. CRT's are vacuum filled and so never have this problem. When a radar display is sent to JRC America for condensation a gasket is placed around the LCD (only needed on early models), the inside of the plastic window is coated with anti-fog wax and a desiccant pack is attached to the inside of the case.
If you ever need to renew the anti-fog coating just remove the 4 case corner screws, carefully separate the halves and lay it out on a clean surface. The front half has six screws which holds down a metal shield.
Remove the screws, lift off the metal shield and also lift the LCD assembly up and out of the way. Coat the inside of the window with anti-fog wax and buff with a clean cloth until clear. There are several brands available and as far as I know any of them will work well. However, make sure you use a wax rather than a liquid as the wax will last longer. When we coat units, we are presently using a product from the following company: http://www.glassafe.com/catcrap.html.

Display Inoperative #1 – If the radar in-line fuse is blown, check the reverse protection diode first and
replace it with the original type or equivalent.
If TR11 (2SJ312) has been hot enough to melt it’s solder connections, try resoldering first and if that doesn’t correct the problem; replace it. This failure is normally caused by excessive ripple on the vessels DC mains.

Display Inoperative #2– If the display will not power up (must be attached to antenna or simulator) and there is no evidence of overheated parts on circuit board CMC-970, check zener diode CD-22 on the same board. CD-22 is a 1 watt, surface mount, 11V zener diode type U1ZB11 (JRC p/n 5TXAD00925). This diode
has been known to fail, especially on older units, when experiencing power surges on the 12VDC mains
from engine starts etc. Because the power supply input circuit of the radar is “on-line” whenever 12VDC
is applied, it is recommended that the radar as well as other electronics equipment have a “cut-out switch”
or breaker to remove 12 volts when starting engines.
BZ or BRG ERROR – If either of these two error codes appear, check the antenna cable and it’s connections very carefully, especially the jack in the rear of the display, and splices, if any. The most common cause of this failure is over tightening of the antenna cable plug at the back of the display. The pins of the rear 10 pin jack are soldered through to the main processor pcb (CMC-970). If this connector (J1) has broken pins from over tightening or applying excessive torque to remove the cable plug it will have to be replaced. The jack is a JAE type SRCN2A16-10P-TH-N (JRC p/n 5JCAC00728). 1

No Targets – If receiver noise is normal but no targets appear or a barely visible ring is present in the center
of the screen, check to see if the magnetron filament leads are broken. Also, remove the two screws that hold
the magnetron to the waveguide assembly and inspect the ceramic RF port for cracks. If cracked, replace the
magnetron. If the wires have broken, replace them, leaving a shrink loop. Broken filament leads are seen most
often on high speed vessels that have excessive vibration at the antenna location. Both broken leads and
cracked magnetron RF ports may also be the result of mechanical shock.

By the way, all of these radars are still fully supported by JRC with parts and service.

[offgrid64]

it's nice that you jrc people share your radar's marketing history and success, and does lend credibility that the jrc is a solid unit. However I have the mk1500 and it has serious screen fogging problems. When I called jrc they told me to use catkrap on the inside which I did, however has not solved the problem. There should have been a recall on these! Having a brand new radar that doesn't work all the time, where I sail in the ocean off northern california, is just like DRIVING A CAR WHO'S BRAKES WORK SOMETIMES BUT SOMETIMES NOT!! Jrc management taking this problem casually could very possibly lead to someone being run down by a tanker. I don't want to hear any excuses or questions fishing for a way to evade responsibility; I have never gotten it wet. This piece of equipment is what saves human life in the fog and dark and having it be brand new and suddenly become un-useable in the open ocean should NEVER be tolerated. They also should not be advising owners to just take it apart ,do it yourself, removing circuit boards to get to the inside of the lcd screen. They should be apologizing, ups'ing a prepaid shipping box to customers to be able to send it in for quick repair or replacement.

[teejayevans]

I notice there is no handheld radar units (used to just identify if a target is there, its position and maybe velocity). No installation, lower power, and for occasional use could be quite handy). With a built-in GPS receiver, it could display targets by their GPS coordinates, maybe give you a warning beep if target is on a collision course.
Because its handheld its power output would only need to be enough to cover a 10 mile range.
Tom

[svHyLyte]

Originally Posted by Aquah0lic

While motoring my new boat down the Chesapeake bay last week, I ran through about 30 miles of fog that was thick enough to chew. Visability got as low as 100-200 ft and little fishing boats were popping out of the fog so close that emergency course changes barely saved me. During those 5 hours I decided a radar was a safety item.

It will likely only be used in times like those or rare night navigation. I'm looking for something small and cheap with minimal range(5-8 miles maybe) but decent sensitivity. Can anyone recommend a model or have such a model laying around from a refit for sale?

Have a look at the following post. You might find the radar of interest. http://www.cruisersforum.com/forums/...how-69383.html

[capecuddy]

Look for a new leftover BR24 broadband radar somewhere. The new 3G model is only 1200 or so, you might find a leftover BR24 for 1000 or less.

It's a different radar....it is designed to keep you from hitting stuff and stuff from hitting you. Ships at 16 nm aren't likely to hit you. Ships at 1000 feet are. As a radar engineer, I am often surprised at how folks get hung up on performance specs that don't address their needs.

The broadband radars are short range, high range resolution (1 meter), low-power, continuous wave radars that can see targets 30 feet off your gunwales. They see effectively out to 6 to 8 miles depending on your use and needs. They are as safe as a cell phone RF hazard wise. They turn on instantly since they are solid state transmitters.

Check them out with an open mind. I got one this year and it has saved my bacon on several occasions already.

[LadyMJ]

An open array antenna has the best discrimination(target separation) but it's often difficult to find a practical place to mount one. They (open array) has a narrower focal point, allowing finer separation. Proper display alignment is very important in allowing you to see the separation between two closely located targets. Read your manual, keep your screen intensity cranked down, then raise your target level, until you see the "sparkle" from your target returns. With practice (during clear weather on marker buoys) you'll benefit from "good radar returns" in the fog!