On 2006-05-16 11:36:48 +1000, "Pascal" said:

Returning to my old subject, this weekend my friend had made the
software update for his C80 wich now is AIS Ready and we two now have
our respective SR161 AIS receivers working and running with the several
PC software (SeaClear, ShipPlotter, OziExplorer and SOB).

The problem which arises now is related to the availability of only one
NMEA port on the Raymarine C80 chart-plotter. I have not seen it (the
physical installation) but appears that this port already have one
connection that I think, it is the VHF/DSC connection, which is NMEA
IN for VHF and NMEA Out for C80.

The questions a

1) Supposing that the connection from the Gyro (which comes with the AP
Smart Pilot S1G) is made by Seatalk and not on the NMEA port, the NMEA
Out of C80 should be 4800 bps (GPS Out to VHF In) or must be 9600? I
heard anywhere some time ago that DSC mandates 9600... It is true?

The gyro is a board level option on the S1. If it came from the factory
as an S1G there is no external gyro. If it was added later it could be
external or it could be a board level upgrade. You will need to eyeball
it to see if this is so.


2) Since the NMEA IN on the C80 (NMEA Out on the SR161) is 38400 bps,
this NMEA port on the C80 could work using NMEA IN at 38400 bps from
AIS and NMEA Out to VHF at 4800/9600 bps?

AFAIK the baud rade is for both in and out. The C and E series do not
support split baud rates. I may be mistaken on this but I doubt it.


3) The boat has an AP Smart Pilot S1G, which is connected by Sea Talk
with the plotter C80. I do not know if the AP Gyro is connected
directly to C80 by NMEA. I hope that this is not our case. But, if this
would be our situation, it would be possible to disconnect the NMEA
link, so that this NMEA port would be free to connect the AIS receiver?

The AP has NMEA in/out so the current NMEA out to position info to the
VHF radio could be shifted to the AP thus freeing up the C80 NMEA port.



4)In this hypothesis, the output of the AP/Gyro would be routed
automatically via S1G to the C80/Radar /Plotter by SeaTalk? Could be
that this link is already working, since the AP is actually linked to
C80 by Seatalk?

Yes.

--
Regards,
John D Proctor

John Proctor wrote:
On 2006-05-16 11:36:48 +1000, "Pascal" said:

4)In this hypothesis, the output of the AP/Gyro would be routed
automatically via S1G to the C80/Radar /Plotter by SeaTalk? Could be
that this link is already working, since the AP is actually linked to
C80 by Seatalk?

Yes.


With the caveat that radar overlay and MARPA will perform worse. The
reason that Raymarine installs have heading information sent both by
seatalk and NMEA to their chartplotter/radar combinations is that the
heading is only sent once per second on seatalk, whereas it is sent 10
times per second over the NMEA port. This means that the heading can be
synchronized during the radar scan.

Whether this is noticeable in practice depends on your boat (how quickly
it yaws), and expectation level.

--
Kees

Ok but am installing an AIS which could overlay the targets on the
radar screen and calculates the CPA/TCPA; this turns the standard Marpa
function of the RADAR almost superfluous?

Pascal wrote:
Ok but am installing an AIS which could overlay the targets on the
radar screen and calculates the CPA/TCPA; this turns the standard Marpa
function of the RADAR almost superfluous?


As long as the other ships have AIS, yes.

Take a look at a picture I took on-board last year.

http://tinyurl.com/hpozz (small)
http://tinyurl.com/ebmda (full size)

Look carefully at the left part, which is chart overlayed with radar,
MARPA and AIS enabled. You'll see that the gray tail behind AIS target
A70 is much more straight than the green tail behind the MARPA target MR8.

Btw, yes the ship represented by A70/MR8 did almost hit MR7. They hadn't
seen each other apparently (this was in THICK fog on the middle of the
North Sea). MR7 did a pretty wild maneuver at about 200 yards from MR8.
Unfortunately I didn't take a screendump of that! I later asked the
skipper of MR8 whether he'd seen or heard anything. He said he had not,
and that he maintained careful radar watch: he checked the screen every
10 minutes but didn't see anything...

--
Kees

This seems to be very very cool, but the link you showed here is for
members of the Club only, and I can not access the photos . Can you
send the images to me by e-mail?

Thanks

Pascal

Kees Verruijt wrote:

Take a look at a picture I took on-board last year.

http://tinyurl.com/hpozz (small)
http://tinyurl.com/ebmda (full size)

Look carefully at the left part, which is chart overlayed with radar,
MARPA and AIS enabled. You'll see that the gray tail behind AIS target
A70 is much more straight than the green tail behind the MARPA target MR8.

Kees,

I think we need a link directly to the images, I seem to be getting to
an opening page but don't know where to find the photo. You might be
able to see things we are not because of cookies stored on your machine.

On some web pages, especially those using frames, I find it is sort of
difficult, if not impossible, to send a link to one of images or frames.

Jack

--
Jack Erbes in Ellsworth, Maine, USA - jackerbes at adelphia dot net
(also receiving email at jacker at midmaine.com)

Jack Erbes wrote:
Kees Verruijt wrote:

Take a look at a picture I took on-board last year.

http://tinyurl.com/hpozz (small)
http://tinyurl.com/ebmda (full size)

Look carefully at the left part, which is chart overlayed with radar,
MARPA and AIS enabled. You'll see that the gray tail behind AIS target
A70 is much more straight than the green tail behind the MARPA target
MR8.

Kees,

I think we need a link directly to the images, I seem to be getting to
an opening page but don't know where to find the photo. You might be
able to see things we are not because of cookies stored on your machine.

On some web pages, especially those using frames, I find it is sort of
difficult, if not impossible, to send a link to one of images or frames.

Jack


Hi Jack, Pascal,

The site is running a content management system that sometimes thinks it
needs to send everyone back to the start page. Trying it again usually
fixes it. Sorry about this, but I haven't found a fix for this yet.

I just tried the deep-linked tinyurl, and it happened for me as well the
first time; trying it again did indeed fix it.

I'll try to fix this asap.

--
Kees

Kees Verruijt wrote:

snip
Hi Jack, Pascal,

The site is running a content management system that sometimes thinks it
needs to send everyone back to the start page. Trying it again usually
fixes it. Sorry about this, but I haven't found a fix for this yet.

I just tried the deep-linked tinyurl, and it happened for me as well the
first time; trying it again did indeed fix it.

I'll try to fix this asap.

That got it. My problem was that I was stumbling around trying to find
it, the 2nd or 3rd try on the same link brought it up.

Great info, I was curious to see how it looked and worked.

Thanks

Jack


--
Jack Erbes in Ellsworth, Maine, USA - jackerbes at adelphia dot net
(also receiving email at jacker at midmaine.com)

Hi Kees,

I had made a initial look in the site, it is fantastic, not only
because the AIS. I think that the picture you put there is gold. This
picture only, with your comments from this discussion, must convince
anyone to buy a AIS asap. I will take look in it more often.

Thank You very much

Best Regards

Pascal Goncalves
s/v Navstar
Salvador/BA-Brazil
S 13 00/W 038 27

Kees Verruijt wrote:
Pascal wrote:
Ok but am installing an AIS which could overlay the targets on the
radar screen and calculates the CPA/TCPA; this turns the standard Marpa
function of the RADAR almost superfluous?


As long as the other ships have AIS, yes.

Take a look at a picture I took on-board last year.

http://tinyurl.com/hpozz (small)
http://tinyurl.com/ebmda (full size)

It seems the CMS running the site doesn't like the tinyurls so here are
the full links:

http://www.scanner391.net/e107_plugi...album=35&pos=3

http://www.scanner391.net/e107_plugi...282&fullsize=1

Alternatively, go to http://www.scanner391.net then choose Gallery -
scroll down to Technical Details - AIS.


Look carefully at the left part, which is chart overlayed with radar,
MARPA and AIS enabled. You'll see that the gray tail behind AIS target
A70 is much more straight than the green tail behind the MARPA target MR8.

Btw, yes the ship represented by A70/MR8 did almost hit MR7. They hadn't
seen each other apparently (this was in THICK fog on the middle of the
North Sea). MR7 did a pretty wild maneuver at about 200 yards from MR8.
Unfortunately I didn't take a screendump of that! I later asked the
skipper of MR8 whether he'd seen or heard anything. He said he had not,
and that he maintained careful radar watch: he checked the screen every
10 minutes but didn't see anything...


--
Kees