T&T: A Radar Question and ARPA

[John Ford]

I had ARPA on my Navnet2 and now have it on my Navnet 3d and I agree  
it's wonderful.  But I like the fact that AIS picks up on all kinds of  
other things like the other day I was coming into Naptown after a  
night cruise and it found this small dink that was coming across in  
front of me with no lights.  Or sometimes when I'm trying leave  
Naptown it will pick up all those sailboats doing various races and  
give me a nice ETA so I can modify my course.  But n the downside it  
does pick up birds and crab pots every once in a while as targets(I  
don't mind the crabpots so much) and quickly fill up the screen with  
targets.  So how much do I like ARPA(No "M" in front of it).  If given  
a choice I would never have a boat without it again.

AIS??  Same thing. By the way the way this time I upgrade to Class A  
AIS(from recieve only) and with the Navnet 3d it's amazing.  With a  
click I get a ton of information, and the plotter even shows you when  
the ships are turning, etc.  Very nice to know where the big boys  
are.  I can't wait till some of the smaller(Big boats) get it as  
well.   Examples?  I saw a tug that came down the chesapeake, a few of  
the party/tour boats in Annapolis don't have it, etc.  By the way for  
a nice mistake I saw a boat called Donna Marie who was transmitting a  
false beam width of 70m and a length of 30m if I remember correctly.   
I wonder when the CG or someone is going to start policing some of  
what people are transmitting.

John Ford
KK44 Feisty Lady
Annapolis, MD


On Aug 19, 2008, at 7:08 AM, Truelove39 at aol.com wrote:

> We have the 1942,
> which has ARPA and ARPA is wonderful. However, you will find, once  
> you have
> AIS, how long it takes from acquisition for ARPA to become really  
> accurate.  If
> you are watching both, trust the AIS!