Yup, a Bluetooth one at that! I still need to send it in for the AIS port
upgrade though. The MiniPlex has been really nice to have on board.

Same thing onboard of Motion².
I have setup a Raymarine E80 together with Raymarine S3G course
computer (build in rate gyro!) together with AIS (via Easyais receiver)
and all NMEA data of the Seatalk bus via a graphic ST60 display. All
NMEA data flows go via Multiplexer to Bluetooth (and laptop behind it)
as well as to the E80 (at baud rate 38k).
The baud rate is very important due to the amount of NMEA data of the
RateGyro, other NMEA and AIS (more the 200 hits in the Rotterdam area).
The normal 4k NMEA speed is simply to slow to transport all the data.
With the mulitplexer receiving multiple data streams (from S3g and
EasyAis and ST60) at 4k and sending it out at 38k to E80 (and
Bluetooth), it all works without any collisions or loss of data.

Dirk

"Paul" wrote in
:


"Jim" wrote in message
. ..
Paul wrote:
Has anyone seen a ship position as reported by AIS being off by over
one nautical mile?

snip
Any thoughts?

Thanks,
Paul

This is really off the wall but is there a possibility that the datum
being used was that far off? Isn't the LAT/LON calculated for the chart
datum?
Jim

I don't think so, since the chart datum isn't an issue unless the
positions are being shown on a chart (whereas my display is similar to a
radar screen). Even so, my boat's position relative to the ship's
position should be displayed correctly regardless of any datum
discrepancies. What I've got is a situation where a ship that is
physically to the north of me is transmitting a latitude that is to the
south of me.

I'm not completely ruling out cockpit error or bad code on my part, but
I can't find it and the raw data seems to exonerate me. If anyone wants
to help figure it out, here is the minimum NMEA data capture that shows
the situation. The first line is my position, and the second is the AIS
message from the ship:

$M2RMC,225040,A,4038.518,N,15149.375,W,5.6,072.5,0 40806,014.5,E,D*6
!AIVDM,1,1,,A,15@HsT001wE8wopG@0K5:3=N0@L6,0*6

The "$M2" has been substituted to indicate which multiplexer port the
data came from.
My position is 40.642433 deg (N), -151.820917 deg (W)
The reported ship position is 40.630167 deg (N), -151.822000 deg (W)
The range and bearing to the ship are 0.7NM, 183.8 deg true

Trust me, the ship was actually to the north. I have photos!

-Paul

I really don't know much about AIS data and how often ships report, but do
other reports from that ship show it moving in a reasonable manner?

-- Geoff

"Meindert Sprang" wrote in
:

Hey, that's a nice feature. Smells like a MiniPlex to me....

Meindert


SALESMAN! SALESMAN ALERT!!.....(c;

--
There's amazing intelligence in the Universe.
You can tell because none of them ever called Earth.

"Paul" wrote in
:

At the moment I am using a second bluetooth channel to connect
the AIS receiver to the PocketPC, but I hope that I with the upgrade I
can run everything through the MiniPlex.



Oh, oh....WARNING WARNING....HE'S BYPASSING NMEA ALTOGETHER!

Next thing you know he'll insist all instruments in the whole boat be
Bluetooth....negating needing multiplexers or even wires to make it all
talk to each other!

What a pleasure THAT will be to install! I'm all for it!

I can hear it in the Bluetooth headset telling the helmsman, "Come left to
course 085. May I energize the autopilot for you? Say 'yes' or 'no'."

"Radar, how far is that ship just off the port bow?"...."Eight point four
nautical miles. I'm tracking it for collision avoidance, sir. Please
slack the sheet on the Genoa. I'm detecting it stalling at this relative
wind setting, slowing us down."

No knobs at all at the helm. You just tell it what you want through your
Bluetooth headset.....(c;

--
"Thank you, HAL."..."You're quite welcome, Dave."
There's amazing intelligence in the Universe.
You can tell because none of them ever called Earth.

Well Larry,
I just put almost that on an owners new boat.
http://www.tacktick.com/
It's all BT and solarpowered (except the depth sounder needs a battery).
It doesn't quite have the functionality you looking for, but may with
the next firmware upgrade.
Matt Colie

Larry wrote:
"Paul" wrote in
:


At the moment I am using a second bluetooth channel to connect
the AIS receiver to the PocketPC, but I hope that I with the upgrade I
can run everything through the MiniPlex.




Oh, oh....WARNING WARNING....HE'S BYPASSING NMEA ALTOGETHER!

Next thing you know he'll insist all instruments in the whole boat be
Bluetooth....negating needing multiplexers or even wires to make it all
talk to each other!

What a pleasure THAT will be to install! I'm all for it!

I can hear it in the Bluetooth headset telling the helmsman, "Come left to
course 085. May I energize the autopilot for you? Say 'yes' or 'no'."

"Radar, how far is that ship just off the port bow?"...."Eight point four
nautical miles. I'm tracking it for collision avoidance, sir. Please
slack the sheet on the Genoa. I'm detecting it stalling at this relative
wind setting, slowing us down."

No knobs at all at the helm. You just tell it what you want through your
Bluetooth headset.....(c;

"Matt Colie" wrote in message
...
Well Larry,
I just put almost that on an owners new boat.
http://www.tacktick.com/
It's all BT and solarpowered (except the depth sounder needs a battery).

Not quite. They do not use BT, that would use too much energy. Tacktick
developed their own very low power radio and protocol for this. It's a shame
they still need a wire to your computer. We made a customized BT multiplexer
for them, but when the prototypes were ready, they bailed out....

Meindert

Matt Colie wrote in news:A8%Ig.1676$Wf3.379
@newsfe02.lga:

I just put almost that on an owners new boat.
http://www.tacktick.com/
It's all BT and solarpowered (except the depth sounder needs a
battery).
It doesn't quite have the functionality you looking for, but may with
the next firmware upgrade.
Matt Colie



Lionheart is wifi-powered, herself. The serial port on a Noland
multiplexer goes to a Webfoot serial-to-ethernet interface:
http://www.i****chdogs.com/DataSheets/WF111803.pdf
It's fully DHCP addressable and gets its IP from a Netgear wireless
router's Ethernet port. Up to 256 wifi devices can connect to it, like
The Cap'n running in the nav laptop through the "virtual serial port"
software that came with the Webfoot. This handles the problem of serial
interface only on The Cap'n's archaic interface. With the Wifi laptop,
you can get data off the boat even up in the parking lot of the marina,
half a mile away.

One day I happened to have the laptop in my haulings and stopped by the
marina office to discuss an electrical problem due to salt rot in the
pedestal box. "Which slip is your boat in?", they asked me. I couldn't
remember the number, so whipped out the laptop and brought it out of
hibernation as I knew the system on the boat was running when I left.
Booted the Cap'n and clicked FIND SHIP zoomed in tight and said, "Right
HERE on J-dock, as you can see by the live display from our network.", as
the marina people noticed the boat moving slightly on her GPS string and
the depth changing slightly because the tide happened to be ripping out.

I think we could sail it from the beach or dingy quite a ways away, sorta
"remote control". With this in mind, I WEP protected the router so some
smartassed competitor in a race couldn't take control...not good...(c;

With the wifi link, it all integrates quite nicely to the old NMEA
network, just like it were on a wired serial cable. It's totally
transparent to The Cap'n and the users, who do nothing but turn it on.
Great fun laying on a beanbag with the computer on your lap, beer in one
hand, clicking a new waypoint and calling back to the slaves in the
cockpit, "COMING ABOUT!" as the big wheel spins over by the B&G Pilot
tugging on her rudder post bellcrank.

Look on their faces when it worked the first time?......PRICELESS.

Larry
Third Mate - Bilge Pumps and Electronics

--
There's amazing intelligence in the Universe.
You can tell because none of them ever called Earth.

"Meindert Sprang" wrote in
:

Not quite. They do not use BT, that would use too much energy.
Tacktick developed their own very low power radio and protocol for
this. It's a shame they still need a wire to your computer. We made a
customized BT multiplexer for them, but when the prototypes were
ready, they bailed out....



What a waste when the wifi I installed works so good. It comes with the
virtual serial port for the old nav software to install into the laptop(s).
The Webfoot:
http://www.i****chdogs.com/DataSheets/WF111803.pdf
interfaces your serial port data to the wifi link, automatically, on
bootup. All you have to tell the virtual serial port is what IP the
Webfoot is using, which is always 192.168.0.2 on the Netgear wifi.

Shame they're still draggin' the wire around or some awful-priced custom
radio system. Wifi doesn't use any power and it all runs great off the 12V
battery system.

I'm afraid BT might not have the range through the fiberglass and coring
materials to get through the whole boat. Wifi easily does and is CHEAPER!

--
There's amazing intelligence in the Universe.
You can tell because none of them ever called Earth.

Larry wrote:
Matt Colie wrote in news:A8%Ig.1676$Wf3.379
@newsfe02.lga:


I just put almost that on an owners new boat.
http://www.tacktick.com/
It's all BT and solarpowered (except the depth sounder needs a

battery).

It doesn't quite have the functionality you looking for, but may with
the next firmware upgrade.
Matt Colie




Lionheart is wifi-powered, herself. The serial port on a Noland
multiplexer goes to a Webfoot serial-to-ethernet interface:
http://www.i****chdogs.com/DataSheets/WF111803.pdf
It's fully DHCP addressable and gets its IP from a Netgear wireless
router's Ethernet port. Up to 256 wifi devices can connect to it, like
The Cap'n running in the nav laptop through the "virtual serial port"
software that came with the Webfoot. This handles the problem of serial
interface only on The Cap'n's archaic interface. With the Wifi laptop,
you can get data off the boat even up in the parking lot of the marina,
half a mile away.

One day I happened to have the laptop in my haulings and stopped by the
marina office to discuss an electrical problem due to salt rot in the
pedestal box. "Which slip is your boat in?", they asked me. I couldn't
remember the number, so whipped out the laptop and brought it out of
hibernation as I knew the system on the boat was running when I left.
Booted the Cap'n and clicked FIND SHIP zoomed in tight and said, "Right
HERE on J-dock, as you can see by the live display from our network.", as
the marina people noticed the boat moving slightly on her GPS string and
the depth changing slightly because the tide happened to be ripping out.

I think we could sail it from the beach or dingy quite a ways away, sorta
"remote control". With this in mind, I WEP protected the router so some
smartassed competitor in a race couldn't take control...not good...(c;

With the wifi link, it all integrates quite nicely to the old NMEA
network, just like it were on a wired serial cable. It's totally
transparent to The Cap'n and the users, who do nothing but turn it on.
Great fun laying on a beanbag with the computer on your lap, beer in one
hand, clicking a new waypoint and calling back to the slaves in the
cockpit, "COMING ABOUT!" as the big wheel spins over by the B&G Pilot
tugging on her rudder post bellcrank.

Look on their faces when it worked the first time?......PRICELESS.

Larry
Third Mate - Bilge Pumps and Electronics


I think you may want to go a little farther than depending on WEP for
protecting your network... Netstumbler requires about 1 minute's worth
of traffic to break a WEP key.

bob

"Larry" wrote in message
...
Shame they're still draggin' the wire around or some awful-priced custom
radio system. Wifi doesn't use any power and it all runs great off the
12V
battery system.

To say that Wifi does not use any power is a bit steep. For instance, the
Wifo module I'm planning to use in my Wifi mux uses 450mA at 3.3V. Compare
that to a BT module consuming 20mA.
And the RF circuits in the Tacktick units are even more low power, being
solar powered and able to run some 50-60 hours without charge. Their power
budged is so low that they had massive problems when they developed the big
displays with an LCD area compared to the large B&G instruments. Go figu
not enough power to drive the LCD!

I'm afraid BT might not have the range through the fiberglass and coring
materials to get through the whole boat. Wifi easily does and is CHEAPER!

Dunno, the BT we use is a class 1, with a range up to 200 meters. If you
stick a class 1 BT dongle in your laptop too, you'll have about the same
range as Wifi but on a much lower power budget.

A nice detail: the well known sailor Pete Goss used Tacktick on his last
Round Britain race and hooked it up to our BT mux to get the data on hus
ruggedized tablet PC while sitting on the outriggers of his trimaran. Lucky
for us, Tacktick's sales manager told him to use our thingy :-)

Meindert