Cruisers Forum
 


Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 24-09-2017, 09:25   #1
Registered User

Join Date: Aug 2016
Location: ABC's
Boat: Prout Snowgoose 35
Posts: 1,756
Simrad / B&G radar guard zone alerts

I've got a Simrad 3g (whatever that means) radar and NSS8 chrplotter.

When sailing at night I usually set guard zones to alert me of the presence of large ships and other things that popup on radar.

I've found that the I get an alert when something enters a particular guard zone. This is expected behaviour. I usually then check to see if the ship is a danger or not. Most of the time it isn't. However no sooner have I dismissed the alert and I get it again for same ship.

It's got to the point where I have to stand there constantly cancelling alerts for 10 minutes until the ship has passed my guard zone, or turn the zones off until the ship has gone.

Is that standard with radar systems? Or is mine just subpar.

The expected behaviour in my mind, is that the radar system should alert me. I see the alert and dismiss it, and now the radar should not alert me again for particular vessel/signature.
mikedefieslife is offline   Reply With Quote
Old 24-09-2017, 09:44   #2
Registered User

Join Date: Jun 2013
Location: canada
Posts: 4,634
Re: Simrad / B&G radar guard zone alerts

I have not used the alarm. But I would guess it should work as you say.

Do you have the ri10 radar box with a connected heading Input? That might help if you Don't.
smac999 is offline   Reply With Quote
Old 24-09-2017, 09:58   #3
Marine Service Provider

Join Date: Dec 2016
Location: Toronto On Canada
Boat: Bristol 45.5
Posts: 736
Re: Simrad / B&G radar guard zone alerts

I have the 4G radar, the G means generation.

My alarm zone does the same thing , I have yet to figure out how to have it not sound again for the same contact . Im not really sure you can , maybe if you give it an assigned name like on ASI , I will have to take a look at the manual to find out for sure . What I usually do is make the guard zone smaller and if that contact comes into that zone then I know it is getting closer .

Regards John.
Typhoon is offline   Reply With Quote
Old 24-09-2017, 10:18   #4
Registered User

Join Date: Aug 2016
Location: ABC's
Boat: Prout Snowgoose 35
Posts: 1,756
Re: Simrad / B&G radar guard zone alerts

The software seems very basic.

I don't have the heading sensor, so that might improve things a bit as you can then acquire targets. I thought it would be able to pick up the headings from my compass gyro that I use for autopilot, but it seems it must be connected directly to the radar break out box. That means investing in another compass/heading sensor unless the ri10 will pass on heading info over NMEA2000.

I understand that Simrad/Navico has problems with MARPA according to some threads, so I'm loathe to spend more money if it's not going to work.

The only way to get more advanced software is to change unit which also means changing MFD.

I imagine what is happening is that for vessels moving at angles, the signature is ever changing the software thinks it is a new target.

It's a pain on night crossing as I'm woken from my little cat naps, then have to stand there for 10 minutes or more dismissing alarms.
mikedefieslife is offline   Reply With Quote
Old 24-09-2017, 10:30   #5
Moderator Emeritus
 
a64pilot's Avatar

Cruisers Forum Supporter

Join Date: Oct 2013
Location: Jacksonville/ out cruising
Boat: Island Packet 38
Posts: 31,351
Simrad / B&G radar guard zone alerts

I don't use the guard zones much, my reason is false alarms, occasionally I believe sea state sets the thing off. Making the zone thin helps. Mine is a 4G, I had to have a heading sensor in order to make radar overlay and I believe the alarms work.
My Radar is on a pole, not the mast
a64pilot is offline   Reply With Quote
Old 24-09-2017, 10:46   #6
Registered User

Join Date: Aug 2016
Location: ABC's
Boat: Prout Snowgoose 35
Posts: 1,756
Re: Simrad / B&G radar guard zone alerts

I turned my gain down to low 30s that stopped false alarms. I also turned the target zone sensitivity down too. It still easily picks up containers and smaller motorboats. Oddly I've not come across any Yachts at night in the Med.

If I attach my heading sensor directly to the ri10 box. Can I still use it for the autopilot or will the radar not pass on that information?
mikedefieslife is offline   Reply With Quote
Old 24-09-2017, 23:59   #7
Registered User

Join Date: Jun 2013
Location: canada
Posts: 4,634
Re: Simrad / B&G radar guard zone alerts

If you have a pilot you already have a heading sensor. If it's nmea 2000 you need to add the ri10 box to the n2k backbone. You'll need a simnet to n2k adapter. Unless your pilot is also simnet.

If your pilot / heading is 183. Simrad makes a different ri box.


Quote:
Originally Posted by mikedefieslife View Post
The software seems very basic.

I don't have the heading sensor, so that might improve things a bit as you can then acquire targets. I thought it would be able to pick up the headings from my compass gyro that I use for autopilot, but it seems it must be connected directly to the radar break out box. That means investing in another compass/heading sensor unless the ri10 will pass on heading info over NMEA2000.

I understand that Simrad/Navico has problems with MARPA according to some threads, so I'm loathe to spend more money if it's not going to work.

The only way to get more advanced software is to change unit which also means changing MFD.

I imagine what is happening is that for vessels moving at angles, the signature is ever changing the software thinks it is a new target.

It's a pain on night crossing as I'm woken from my little cat naps, then have to stand there for 10 minutes or more dismissing alarms.
smac999 is offline   Reply With Quote
Old 25-09-2017, 19:13   #8
Registered User

Join Date: May 2017
Location: Australia
Boat: 130' Wooden sailing Ketch
Posts: 25
Images: 1
Re: Simrad / B&G radar guard zone alerts

Sounds normal to me. Radar cannot distinguish between an 'already alerted' target and a 'possible new target' especially when both are moving when it comes to entering guard zones. A disturbed catnap or a collision......??!
Julian Alcorso is offline   Reply With Quote
Old 25-09-2017, 21:44   #9
Registered User

Join Date: Jul 2005
Location: Bellingham
Boat: Outbound 44
Posts: 9,319
Re: Simrad / B&G radar guard zone alerts

Quote:
Originally Posted by Julian Alcorso View Post
Sounds normal to me. Radar cannot distinguish between an 'already alerted' target and a 'possible new target' especially when both are moving when it comes to entering guard zones. A disturbed catnap or a collision......??!
My Furuno does.
__________________
Paul
Paul L is offline   Reply With Quote
Old 26-09-2017, 00:23   #10
Registered User

Join Date: May 2017
Location: Australia
Boat: 130' Wooden sailing Ketch
Posts: 25
Images: 1
Re: Simrad / B&G radar guard zone alerts

Quote:
Originally Posted by Paul L View Post
My Furuno does.
What I was trying to say is that once a target has entered a guard zone it will continue to alert you. If another vessel enters the zone it will also alert you but the alert will still continue when one leaves the zone. At least that's how it works on my Simrad Halo.
Thus far I have not found a way to turn the alert off other than to re-set the size of the various guard zones. If I have a vessel inside my inner guard zone I want to be awake and alert so I never turn that one off!
Julian Alcorso is offline   Reply With Quote
Old 26-09-2017, 01:06   #11
Registered User

Join Date: Jul 2005
Location: Bellingham
Boat: Outbound 44
Posts: 9,319
Re: Simrad / B&G radar guard zone alerts

Quote:
Originally Posted by Julian Alcorso View Post
What I was trying to say is that once a target has entered a guard zone it will continue to alert you. If another vessel enters the zone it will also alert you but the alert will still continue when one leaves the zone. At least that's how it works on my Simrad Halo.
Thus far I have not found a way to turn the alert off other than to re-set the size of the various guard zones. If I have a vessel inside my inner guard zone I want to be awake and alert so I never turn that one off!
I understand what happens on your Simrad. I was just pointing out that my Furuno does not function that way. A target enters the guard zone and an alarm is started. The unit then starts to track the target via marpa. You hit Cancel to turn the audio alarm off. The unit continues to Target the target. When the target finally exits the guard zone another alarm is started.
__________________
Paul
Paul L is offline   Reply With Quote
Old 26-09-2017, 01:43   #12
Registered User

Join Date: May 2017
Location: Australia
Boat: 130' Wooden sailing Ketch
Posts: 25
Images: 1
Re: Simrad / B&G radar guard zone alerts

Quote:
Originally Posted by Paul L View Post
I understand what happens on your Simrad. I was just pointing out that my Furuno does not function that way. A target enters the guard zone and an alarm is started. The unit then starts to track the target via marpa. You hit Cancel to turn the audio alarm off. The unit continues to Target the target. When the target finally exits the guard zone another alarm is started.
Got it Thanks!
Julian Alcorso is offline   Reply With Quote
Old 26-09-2017, 03:43   #13
Moderator
 
Dockhead's Avatar

Cruisers Forum Supporter

Join Date: Mar 2009
Location: Denmark (Winter), Helsinki (Summer); Cruising the Baltic Sea this year!
Boat: Cutter-Rigged Moody 54
Posts: 33,750
Re: Simrad / B&G radar guard zone alerts

Quote:
Originally Posted by Paul L View Post
My Furuno does.
Not the Furunos I've used. All the recreational radars I've ever used, including Furunos, work the same way in this respect -- alarm when a target enters or leaves the guard zone (you can switch off the alarm for leaving if you want). Alarm will repeat as often as the target moves in or out. You will also get an alarm every time a sweep fails to turn up the same target and it reappears on another sweep.

Furunos do have ARPA which works differently from MARPA on other brands -- can automatically acquire ARPA targets and alarm for dangerous CPA/TCPA and lost target -- but the OP is not talking about this -- he's talking about the guard zones.


This whole thing can be a PITA, but here is how I deal with it, FWIW.

The alarms are intended to get you to look at the radar screen, when you are not otherwise staring at it all the time. This is a massive enhancement to watchkeeping -- even in the day time. The Simrad/B&G 4G radar is particularly good because it has very few false returns, so very few false alarms. This is the most useful feature of this radar in my opinion.

Once the alarm has gone off, get to the helm, shut off the alarm, and keep an eye on the screen. You don't need the alarms if you're watching the screen. Then turn them back on only when the coast is really clear.

I do the same thing with AIS alarms. I only turn them on when I'm well offshore and out of traffic areas. Their purpose is to tell me I need to get behind the helm or to the nav table and start watching carefully and analyzing the traffic. Once I'm doing that, I don't need the alarm any more. Targets fitting the "dangerous AIS target" criteria I set will be bolded on the screen, so the alarm is superfluous if I'm watching the screen carefully.
__________________
"You sea! I resign myself to you also . . . . I guess what you mean,
I behold from the beach your crooked inviting fingers,
I believe you refuse to go back without feeling of me;
We must have a turn together . . . . I undress . . . . hurry me out of sight of the land,
Cushion me soft . . . . rock me in billowy drowse,
Dash me with amorous wet . . . . I can repay you."
Walt Whitman
Dockhead is offline   Reply With Quote
Old 26-09-2017, 04:27   #14
Registered User
 
Sailmonkey's Avatar

Join Date: Sep 2009
Location: Houston
Boat: '76 Allied Seawind II, 32'
Posts: 9,626
Re: Simrad / B&G radar guard zone alerts

Quote:
Originally Posted by Dockhead View Post
Not the Furunos I've used. All the recreational radars I've ever used, including Furunos, work the same way in this respect -- alarm when a target enters or leaves the guard zone (you can switch off the alarm for leaving if you want). Alarm will repeat as often as the target moves in or out. You will also get an alarm every time a sweep fails to turn up the same target and it reappears on another sweep.

Furunos do have ARPA which works differently from MARPA on other brands -- can automatically acquire ARPA targets and alarm for dangerous CPA/TCPA and lost target -- but the OP is not talking about this -- he's talking about the guard zones.


This whole thing can be a PITA, but here is how I deal with it, FWIW.

The alarms are intended to get you to look at the radar screen, when you are not otherwise staring at it all the time. This is a massive enhancement to watchkeeping -- even in the day time. The Simrad/B&G 4G radar is particularly good because it has very few false returns, so very few false alarms. This is the most useful feature of this radar in my opinion.

Once the alarm has gone off, get to the helm, shut off the alarm, and keep an eye on the screen. You don't need the alarms if you're watching the screen. Then turn them back on only when the coast is really clear.

I do the same thing with AIS alarms. I only turn them on when I'm well offshore and out of traffic areas. Their purpose is to tell me I need to get behind the helm or to the nav table and start watching carefully and analyzing the traffic. Once I'm doing that, I don't need the alarm any more. Targets fitting the "dangerous AIS target" criteria I set will be bolded on the screen, so the alarm is superfluous if I'm watching the screen carefully.


+1

This is how ours works as well. The "targets" are just echo blobs that appear and disappear depending on how the sweep catches them.
Sailmonkey is offline   Reply With Quote
Old 26-09-2017, 19:57   #15
Registered User

Join Date: Jul 2005
Location: Bellingham
Boat: Outbound 44
Posts: 9,319
Re: Simrad / B&G radar guard zone alerts

Quote:
Originally Posted by Dockhead View Post
Not the Furunos I've used. All the recreational radars I've ever used, including Furunos, work the same way in this respect -- alarm when a target enters or leaves the guard zone (you can switch off the alarm for leaving if you want). Alarm will repeat as often as the target moves in or out. You will also get an alarm every time a sweep fails to turn up the same target and it reappears on another sweep.

Furunos do have ARPA which works differently from MARPA on other brands -- can automatically acquire ARPA targets and alarm for dangerous CPA/TCPA and lost target -- but the OP is not talking about this -- he's talking about the guard zones.


This whole thing can be a PITA, but here is how I deal with it, FWIW.

........
My Furuno Navnet3D works as I described it above. When a target enters the Guard Zone it is automatically tracked by ARPA. If it is missed on multiple sweeps the ARPA does not loose the target, so you do not get a new Alarm when it shows back up on a sweep. The ARPA tracking is set so only a target that shows up inside the Guard Zone(s) gets automatically tracked. Works very well.

If you have system that excessive alarms, then ultimately the alarms will end up disabled or ignored.
__________________
Paul
Paul L is offline   Reply With Quote
Reply

Tags
radar, simrad

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Watchdog_pi - AIS Guard Zone GUID PierreFDK OpenCPN 44 01-03-2017 10:29
Simrad NSS7 and Simrad 3G radar gunkylump Marine Electronics 6 26-04-2015 12:15
MA Seeks No-Discharge Zone for Cape & Islands Soundbounder General Sailing Forum 11 12-03-2012 18:00

Advertise Here


All times are GMT -7. The time now is 01:45.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.