"Larry" wrote in message
...
"Pascal" wrote in news:1172160465.780416.309310
@q2g2000cwa.googlegroups.com:

I know that there
are many models of gps/ploters that are AIS enabled,

That all sounds good until you look at what comes out of the AIS at
38,800 baud RS-232 level data....then look at the GPS/Plotters plodding
along on RS-422 (NMEA-0183 isn't RS-232C compatible) at 4800 baud.....

Wrong baud rate, wrong voltage levels, INCOMPATIBLE AS USUAL....

"AIS Enabled" just means they'll read an AIS statement IF IT COMES IN AT
NMEA'S slow baud rate with the rest of the NMEA data. You can't just
plug them in, of course.

On Lionheart, our current configuration is an SR-161 receiver feeding a
Radio Shack RS-232C serial to USB interface cable ($10) plugged into a
USB port on the Dell Latitude notebook running the accompanying virtual
serial port software so The Cap'n nav software can find the 38,800 baud
data stream on what it thinks is a serial port. NMEA system data comes
in on another virtual serial port from my wireless router on the NMEA
system.

The Cap'n regurgitates the AIS data statements at 4800 baud to the NMEA
system so it will show up on any instruments capable of reading it.
SOME, not all, models of Raymarine and Garmin are capable of reading it
from the NMEA stream IF you upgrade their firmware or buy something new.
Currently, seeing the ships on the computer display chart is fine...(c;

I want to add another Webfoot RS-232C to Ethernet adapter to our Wireless
system. When I get that installed, I'm going to feed it the AIS data
from the SR-161 receiver. Being on a separate hard-wired Ethernet
address on our LAN, I'll be able to connect to its LAN IP address with
the second virtual serial port driver that comes with the Webfoot and can
eliminate the current Radio Shack hard-wired USB connection AIS is
attached to......making both NMEA at 4800 baud and AIS at 38,800 baud
available to The Cap'n WIRELESSLY so it will run anywhere on the
boat...or even at the yacht club bar if we dock the boat at the club...
(c;


NMEA out/in 1 4800 baud--Webfoot 1--Netgear wireless router port 1|
|
AIS SR-161-38.6Kbaud-----Webfoot 2--Netgear wireless router port 2|
|
RF-wifi radio link--------------|

RF-Wifi radio in laptop-|-Virtual serial COM2--The Cap'n NMEA in
|
|-Virtual serial COM3--The Cap'n AIS in



Larry
--
http://www.youtube.com/watch?v=fEJmc...elated&search=

I'm surprised the Cap'n can pass through (relay) AIS NMEA sentences, but
who is going to read them at 4800baud? All equiment that accept AIS do this
at 38400.
Also, if there is dense AIS traffic, you would soon run into bandwidth
problems running at 4800, the very reason why AIS uses 38400.
plano

"Bjarke M. Christensen" bjarkeNG@grevestrand_punktum_danmark wrote in
message ...
Does it make sense ??

It's hard enough already to read the disply on portable units. Adding AIS
data on top will just make it totally unreadable. You might be able to
read
at home, in good light and with you glasses on, but in the boat, dark,
raining and in a "windy and critical" situation, you wouldn't be able to
see
anything ....

Bjarke



Totally agreed, but what is "portable"? I don't think that there should be
any "portable" electronics on a boat. In heavy weather they become missiles
or are lost overboard. I cringe when I hear people talk about laptops that
can be used "anywhere" on the boat. They should be bolted to the chart
table, and by bolted I don't mean kept in place by a piece of shockcord.
plano







"Pascal" wrote in message
ups.com...
Anybody knows one? I am using a non portable solution: SR161 + Laptop
+ GpsMap 276C. I would like to have a gps/plotter portable (or
handheld), WeatherProof and useable in the cockpit. I have asked
Garmin to give the AIS receiver supprt on the GpsMap 276C but after
waiting 2 years I have quit.

Thanks

Pascal

Yes I have a 5 inch display as well and it is almost workable with AIS.
However have in mind that portable are typical below 2-3 inch display and a
2,5 inch display is only 1/4th of a 5 inch.....

I got an eTrex with map support. It's worthless .... Screen is far to small
for anything. Portable gps's should telle you yor position and cource to
next wpt.

Bjarke


"Pascal" wrote in message
oups.com...

Well Bjarke,

I have seen the AIS data on a Garmin GpsMap 3205 and I reputed the 5"
size very good. Course that the display of targets on a RayMarine C80
I had seen too, is better. All wil depend on the zoom level you set
the unit, and I think that in regions with no very heavy traffic like
here, if it will show about 10 targets at the 5 nm range, this will be
very visible.

Anyway, in a critical situation, I could reduce the chart detail on
the plotter (declutter) and the best thing will be to hear the alarm
and see the ship name, course, speed etc. I have used Ais in my
Notebook with SeaClear and ShipPlotter and it is fine, the problem is
the size of the laptop, the current drain, the mess of cables etc. And
what I want is to have all this information at the helm, not below at
the nav table.

Regards

Pascal


On 22 fev, 16:47, "Bjarke M. Christensen"
bjarkeNG@grevestrand_punktum_danmark wrote:
Does it make sense ??

It's hard enough already to read the disply on portable units. Adding AIS
data on top will just make it totally unreadable. You might be able to
read
at home, in good light and with you glasses on, but in the boat, dark,
raining and in a "windy and critical" situation, you wouldn't be able to
see
anything ....

Bjarke

On 22 fev, 20:08, "Bjarke M. Christensen"
bjarkeNG@grevestrand_punktum_danmark wrote:
Yes I have a 5 inch display as well and it is almost workable with AIS.
However have in mind that portable are typical below 2-3 inch display and a
2,5 inch display is only 1/4th of a 5 inch.....


I agree that eTrex with map is useless. By portable I am not talking
for anything smaller than a 276C screen (3.8 "), but preferable,
something like 5-7 " (Origami/UMPC like, why not?).

I do not understand why the resistance to something portable in the
boat. I know that there is more than 2 AIS solutions based on Pocket
PC (PPC) and I found it very very good, and the only restriction
being the lack of weatherproofing in any PPC.

And as I told before, I do not think that a map is necessary for use
with AIS, a radar like diagram or even the classical street like
diagram would be very useful.

"plano" wrote in
:

I'm surprised the Cap'n can pass through (relay) AIS NMEA sentences,
but who is going to read them at 4800baud? All equiment that accept
AIS do this at 38400.
Also, if there is dense AIS traffic, you would soon run into bandwidth
problems running at 4800, the very reason why AIS uses 38400.
plano




Listen to your VHF radio tuned to the two AIS channels. The traffic is
bursts of data with LOTS of dead time. At some point, you're right, it
could become saturated. But 4800 baud would handle the data I've heard
coming over the two channels very easily in busy Charleston harbor.

Larry
--
http://www.youtube.com/watch?v=fEJmc...elated&search=

ppc solutions are for home experiments. My Compaq Ipaq lasted for 2 month in
the boat. Then it was dead. And I wasn't (very) sorry. It was to difficult
to read in dayligt due to the glossy screen...

Bjarke




"Pascal" wrote in message
oups.com...
On 22 fev, 20:08, "Bjarke M. Christensen"
bjarkeNG@grevestrand_punktum_danmark wrote:
Yes I have a 5 inch display as well and it is almost workable with AIS.
However have in mind that portable are typical below 2-3 inch display and
a
2,5 inch display is only 1/4th of a 5 inch.....


I agree that eTrex with map is useless. By portable I am not talking
for anything smaller than a 276C screen (3.8 "), but preferable,
something like 5-7 " (Origami/UMPC like, why not?).

I do not understand why the resistance to something portable in the
boat. I know that there is more than 2 AIS solutions based on Pocket
PC (PPC) and I found it very very good, and the only restriction
being the lack of weatherproofing in any PPC.

And as I told before, I do not think that a map is necessary for use
with AIS, a radar like diagram or even the classical street like
diagram would be very useful.

If averaged over 10 minutes or so, maybe 4800 would offer enough bandwidth
in certain locations, but you just cannot risk that say 20 (long) AIS
sentences are received more or less simultaneously. There is no way 4800
baud (1/8th!! of 38400) will handle that. Any idea how much traffic one
can expect say in the English Channel? It's the worst case scenario that
counts, not the average in Charleston harbor.
plano

"Larry" wrote in message
...
"plano" wrote in
:

I'm surprised the Cap'n can pass through (relay) AIS NMEA sentences,
but who is going to read them at 4800baud? All equiment that accept
AIS do this at 38400.
Also, if there is dense AIS traffic, you would soon run into bandwidth
problems running at 4800, the very reason why AIS uses 38400.
plano




Listen to your VHF radio tuned to the two AIS channels. The traffic is
bursts of data with LOTS of dead time. At some point, you're right, it
could become saturated. But 4800 baud would handle the data I've heard
coming over the two channels very easily in busy Charleston harbor.

Larry
--
http://www.youtube.com/watch?v=fEJmc...elated&search=

"Pascal" wrote in message
ups.com...
Ok, but as I have said, I want a "Portable" unit.. I know that there
are many models of gps/ploters that are AIS enabled, like those more
recent units from Garmin, Navman, Raymarine, etc but none of them are
"portable" (that is, battery operated and easily removable to be used
in another boat and at home).

What about running an AIS application on a Windows Mobile PDA, inside a
waterproof box, using Bluetooth to receive data from an AIS receiver?

Meindert

"Larry" wrote in message
...
"Pascal" wrote in news:1172160465.780416.309310
@q2g2000cwa.googlegroups.com:

I know that there
are many models of gps/ploters that are AIS enabled,

That all sounds good until you look at what comes out of the AIS at
38,800 baud RS-232 level data....then look at the GPS/Plotters plodding
along on RS-422 (NMEA-0183 isn't RS-232C compatible) at 4800 baud.....

You need to get your facts straight! A Raymarine C/E series chartplotter
runs at 38400 baud when in AIS mode. Most likely others do that too....

Oh and besides that, there is also something called NMEA0183-HS which IS
38400 at RS422.

Meindert

What about running an AIS application on a Windows Mobile PDA, inside a
waterproof box, using Bluetooth to receive data from an AIS receiver?

Meindert

I have seen the site of AIS2Ozi software that runs under Ozi/CE in a
PPC using a BT adapter, seems very good. By the way, I have put this
questions here as a provocation to the builders, so that someone
develop the portable AIS that I dream and I would buy it ready to
use, at a low price, some time in future ... I would like something
the size and format of a Origami/UMPC, a TFT screen of 5-7" with touch
screen support, weather proof to be used in the cockpit, and at a cost
of a GpsMap 276C, that is, less than 1K, and it will not need to run
under Windows/Tablet/XP....

Regards

Pascal