Target track history and predition vectors?

[Anonymous]

Hi,

As part of my radar selection process, I have a few questions of NN3D and TZ radar.

1) On NN3D radar, I see a Track History feature that leaves a dot trail where an ARPA or AIS target has been. Is that trail showing true or relative motion? The Echo Trails, which are something different, can be selected to be true or relative, but it's not clear what the Track History is.

2) Also on NN3D, unless I've been dreaming it for the past few years, ARPA targets show a prediction vector showing course and speed of the target. Does that vector show relative or true motion? Looking back through the manual, I don't see any discussion at all about target vectors. I have believed that AIS vectors are true, so have assumed the ARPA vectors were too, but realize I don't really know.

3) The Track History feature appears to have been removed from the TZ radar products. Is that correct? I'm not finding it in the manual anywhere.

4) Does the TZ radar show AIS and ARPA target vectors, and assuming it does, are they true, relative, or selectable as either?

Thanks much, and happy new year!

 

[Johnny Electron]

ARPA and AIS tracks are based on past position (lat/lon) of the target. They are not the same as the selectable echo trails which are for a very limited time. The Predictor line (on both systems) will be selectable between relative and true, as long as you have HEADING data being supplied to the system. Heading is also required if you plan to see AIS on the radar screen or to conduct radar overlay. The TZT does offer track history. You have to turn it On or Off as you require. The NN3D is always tracking. You can hide it but not turn it off.

 

[Anonymous]

I've been reading through the TZTBB Operators manual and can't find where/how you

1) turn on/off the ARPA & AIS tracks and control how long they are

2) where/how you change the predictor vectors between true and relative.

Perhaps I have an old manual or maybe it's not in there? These features are critical to my buying decision, so I want to be certain about them.

Thanks

 

[Johnny Electron]

The NavNet 3D has AIS/ARPA target trails (Track History feature) but the TZT doesn't. Most people are concerned with their own vessel when it comes to tracks, and target tracking feature was dropped to save system overhead. Since the 2012 release of the TZtouch, I think you might be the first one to even notice that it doesn't keep history of other boats. As you already know, you can use echo trails on the radar to provide a bit of target history. The COG vector lines of AIS/ARPA targets are based only on time. The time setting is under MENU - SHIP and TRACK. The "Own ship" COG vector line is selectable between time or distance. The targets, and your COG vector lines length will change based on the settings. The TZtouch radar has three selectable settings under MENU - Radar.
Bearing Scale Mode (Relative, True)
EBL Reference (True, Relative)
Trail Mode (Relative, True)

 

[Anonymous]

OK, so that confirms that the TZ does not have relative motion vectors, just relative motion echo trails. I have to say I'm quite surprised. Relative motion vectors are the basis for all collision avoidance, and supported in all your stand alone radars, even the low end ones. But missing from TZ? I guess the TZ really is just a consumer-oriented device.