Furuno 1623 Radar Says no Heading Pulse

[surfmachine]

Ahoy shipmates, Please help with advice about this message that comes up on my 3 year old Furuno radar, 1623. "no heading pulse". Sometimes "no bearing pulse".

At Penang at the moment and no Furuno agents here, closest is in Singapore!

Any suggestions as to the problem and remedy?

I have checked the signal cable and the connection to the display unit is ok!

Up the mast next, but what to look for?

I ran the self test diagnostics on the scanner and it returned a "NG", but I still get a sweep on the screen and a radar image at all ranges, but it is underlain by the no heading pulse and sometimes no bearing pulse massage, sometimes the message goes away for 20 seconds??

Cheers from Keith.

[svlamorocha]

I am not familiar with that specific model from Furuno but I have fixed other Furuno radar sets. I suggest you check if there is something wrong in a) the piece of equipment aka fluxgate that supplies heading data to the Furuno radar box, or in b) the (probably NMEA) cable between the fluxgate and the Furuno radar box. The fluxgate may or may not be Furuno brand; in fact it may be the same that feeds your autopilot.

Cheers

C

[surfmachine]

Thanks C, the radar is stand alone, no nmea, or interface. Will this error affect the performance of the radar unit, can I still use it?
Keith.

[svlamorocha]

Keith

The manual that I have have seen says that when "the message “NO HEADING PULSE” or “NO BEARING PULSE” appears " you should check that the antenna cable is firmly connected." I hope this helps. That said, this does not make sense to me because the radar display does not even need the antenna or antenna cable to display heading (which comes from a fluxgate if available) but nonsense arising from translation is not uncommon in Furuno manuals printed in English.

My question is: when you do SCANNER TEST following the manual, which answer (NG or OK) you get after each of "HEADING" "BEARING" and "ANTENNA STATUS"?

Cheers

C

[surfmachine]

Thanks C, when I do the antenna check there is only two responses, OK or NG, mine returns NG!

No mention of heading or bearing test?

Will the radar display still be usable without a heading status?

The signal cable is in tight and does not appear to be kinked or broken. Jigglig it has no effect. I am motoring the 65nmiles back to Langkawi now, after collecting my indonesian visa from their embassy, eta 0300 hrs at kuah harbour!

I will go up the mast tomorrow morning and check all connections, maybe take the lid off of the scanner and see what is going on?

Cheers from Keith

[svlamorocha]

I am afraid I can´t help becase the manual that I have does nt match what you report. . I only suggest you read the manual before you decide to open the lid. This antena emits serious radiation and I was advised not to open any radar antenna ever to avoid damaging the shielding..
C

[lateral]

Originally Posted by surfmachine

Thanks C, when I do the antenna check there is only two responses, OK or NG, mine returns NG!

No mention of heading or bearing test?

Will the radar display still be usable without a heading status?

The signal cable is in tight and does not appear to be kinked or broken. Jigglig it has no effect. I am motoring the 65nmiles back to Langkawi now, after collecting my indonesian visa from their embassy, eta 0300 hrs at kuah harbour!

I will go up the mast tomorrow morning and check all connections, maybe take the lid off of the scanner and see what is going on?

Cheers from Keith

I have an Furuno MFD RDP149, which is a plotter/sounder/radar so mine is a bit different
I can't quite figure what your problem is.
Are you getting targets on your screen?
Heading and bearing are two different variables. You don't have heading as you don't have NMEA data input from a flux gate; but when you move your cursor to a target the EBL line offset should give you a bearing (To target) of your vessels current heading (0 deg) to the target. This appears in bottom rh corner of screen. Try it when you have a target of known approx. distance.
The test readout I am not familiar with as diff. to mine. Aside, NG usually aint good!
I suggest clear the memory and restore factory defaults, reboot and set it up again.Can't hurt.
If you give me the exact list of test readouts following the manual I could call the service agent here and get their prognosis and report back.
The radar works fine without heading as this is only needed to overlay on a plotter.
Bearing is not relative to north just target to centerline of your boat so is not needed either. I suspect you have pushed some combination of buttons to get the "no bearing pulse" carry on, hence my suggestion to reset to defaults.
Roly
PS Its awhile since I used mine & I think you get a dash instead of NG if something like an FG is not connected so I can't understand why uou are getting "No heading pulse"?

[lateral]

The logic behind my thinking is that it is working but flashing these messages because it is looking for a compass heading from external source so it can give the bearing to target as a compass bearing. Nudging the wrong buttons can do ***** like this!

[Ziggy]

I think "heading pulse" and "bearing pulse" may refer to the electrical pulses that indicate the radar antenna orientation inside the radome. (the display needs to know the antenna angle to properly draw the radar return on the screen. I would check your display against known targets (like a buoy or another boat.) If they show up on the display in the right place, I think the radar may be useable with some caution. You should also contact Furuno Technical support (via their web site) for advice.

The heading pulse is generated when the antenna rotates by a small magnet located just under it. If you open up the radome you might be able to see if it came mechanically loose or something.

[lateral]

On a quick google of the fault , seems there are multiple reasons for this fault. (Who would have guessed!) Seems like service tech time.
One here:
http://www.thehulltruth.com/marine-e...ing-pluse.html

[Jim Cate]

Originally Posted by svlamorocha

I am afraid I can´t help becase the manual that I have does nt match what you report. . I only suggest you read the manual before you decide to open the lid. This antena emits serious radiation and I was advised not to open any radar antenna ever to avoid damaging the shielding..
C

Your advise was a bit offbase. For starters, one must remove the dome lid in order to attach the cable when installing. Further, there is no shielding to disturb in any radome that I've been involved with.

It is true that you should avoid exposing yourself to the radar beam when it is transmitting, especially your eyes, but with these low powered units a short exposure (if you make a mistake) is not terribly harmful.

Cheers,

Jim

[2una]

Get similar with a Simrad radar from time to time - master reset sorts it out.

[Ziggy]

Originally Posted by 2una

Get similar with a Simrad radar from time to time - master reset sorts it out.

+1... That's the first thing to try. Opening up the radome may be more difficult if it's mounted 20 feet up your mast.

[surfmachine]

Ahoy shipmates, thanks for your comments and advice , much appreciated!!
Have been in phone contact with furuno singapore and it is the reed switch activated by a magnet that sends the heading pulse every rotation, that orientates the display on the screen, which is jumping around 90 degrees or more every sweep!!
Went up and opened it up and checked the magnet and reed switch, all looked ok, now sailing to phuket via Koh Roc and Phi Phi Don, at Phuket will check the reed switch for operation with the multimeter as it passes the magnet, passively!!! Then replace the faulty units or the pcb if switch is ok!??

Steaming at 5 knots in the Kuah channel at present, crew is cooking up a storm of veges and tuna!! Will be a long night without radar, but have a track and made the passage 5 times before! Looking at 17 hrs to KJoh Roc for a night stop friday night then onto Phi Phi for some thai action!!!!

Keep ya posted!

Fair winds from Keith.

[surfmachine]

Hi Lateral, it has no gps connection and the tech told me that connecting it will not cure the problem, an internal fault and quite common I am told. Display is fine but jumps around and the coast rotates 90 degrees!
Keith.