# Best AIS receiver for the buck



## prroots (Nov 13, 2010)

I'm about to outfit a 34 foot sailboat for offshore cruising. It would seem that being able to receive AIS data would be a nice safety feature. The receiver should probably have dual receivers and have the ability to share the VHF antenna with the VHF radio antenna. Also, it should offer NMEA 0183 output as a minimum and perhaps NMEA 2000. Any suggestions on AIS receivers that offer these capability for a reasonable price. I intend to display the output on my laptop. 
Pete


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## sailingdog (Mar 19, 2006)

Why not get a Standard Horizon GX2100 VHF, which has an integrated AIS receiver in a fairly nice DSC VHF unit, with a small display for AIS data.


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## eherlihy (Jan 2, 2007)

sailingdog said:


> Why not get a Standard Horizon GX2100 VHF, which has an integrated AIS receiver in a fairly nice DSC VHF unit, with a small display for AIS data.


If a receiver only is what you want, then the Standard Horizon GX2100 will fit the bill...

However I would suggest that as long as you are going to all the trouble of installing and the expense, you may as well install an AIS Transceiver. A Transceiver will allow other vessels to see you, as well as you seeing them.

Garmin has a nice unit, IIRC ~$600


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## Maine Sail (Jan 6, 2003)

Best receiver value is the Standard Horizon GX2100-AIS. Sends data to any GPS plotter as well..

Red ship is AIS from GX2100-AIS...


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## prroots (Nov 13, 2010)

sailingdog said:


> Why not get a Standard Horizon GX2100 VHF, which has an integrated AIS receiver in a fairly nice DSC VHF unit, with a small display for AIS data.


Thanks. I think that may be the way to go. I'm planning to purchase the Garmin gpsmap 441s. It appears that the gx2100 has 3 NMEA ports with 1 hi speed for ais output, 1 low speed input for gps, and 1 low speed output for dsc. The 441s has a Tx port 1 out, Rx port 1 in, Tx port 2 out, and Rx port 2 in. Any idea how you'd connect things so that both the gx2100 and laptop received gps data from 441s and both 441s and laptop received ais data from gx2100? Can the NMEA 0183 gps output of 441s be paralleled and sent to both gx2100 and laptop and likewise can the ais output of gx2100 be paralleled and sent to both 441s and laptop?

Edit: I do have a USB hockey puck gps which could easily provide gps input to laptop. That still leaves the question on paralleling the ais signal. For some reason, I'd like to share the gps signal from 441s (if possible) and save the hockey puck as a backup.


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## MJBrown (Apr 1, 2009)

Check out the ICOM MXA-5000 receiver. Picks up both A and B signals, uses the exisiting VHF antenna and is easy to connect. Picked one up last year (2009) after the Annapolis Show for $415 from Defender. Works well with my E120.


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## RhodesSwiftsure (Aug 5, 2007)

*Second Vote for MXA-5000*

I've found the MXA-5000 to be very good unit. One really nice and often overlooked feature is that if you wire a GPS _into_ it as well, then it will repeat GPS and AIS nmea data out on a separate PC serial line. I have this wired to a bluetooth serial dongle, and so any laptop onboard can pick up the bluetooth serial connection and see realtime position and AIS data. Very handy (now if only Apple would put a non-crippled bluetooth stack on the iPhone and iPad).


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## jrd22 (Nov 14, 2000)

Does the GX2100 just use the existing VHF antenna cable? If so it seems like a no brainer and it says that my RAM mike will connect to it too.


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## night0wl (Mar 20, 2006)

There are reasons to want receive only...privacy for one! Have you seen those websites that plot ais tracks online? They have prior 30 days of data *OR MORE*!!!! I for one do not want my ais breadcrumbs to be available for all to see. 

For receive only, I agree with the standard horizon matrix. But for me, this meant not only a new VHF, but also now a new ram mic and cabling...it became a $1000 project. Too much.

So I'm investigating the newest ACR dual channel nauticast from on sale for sub-$200 at defender. Getting a dedicated whip VHF antennae and mounting it to the bimini. Redundancy of antennas is a good thing anyway, and can't beat the price.


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## Maine Sail (Jan 6, 2003)

jrd22 said:


> Does the GX2100 just use the existing VHF antenna cable? If so it seems like a no brainer and it says that my RAM mike will connect to it too.


Yes all you need to do is connect the NEMA, power, VHF antenna and the RAM if you have one..


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## prroots (Nov 13, 2010)

Thanks for all the feedback; food for thought. Can anyone help me with my questions on post #5 or refer me to a NMEA wiring tutorial? My basic question is are NMEA ports strictly point-to-point or is there a way to parallel an output port to more than one external NMEA device? I hope I don't have to buy a multiplexer? Thanks
Pete


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## prroots (Nov 13, 2010)

MJBrown said:


> Check out the ICOM MXA-5000 receiver. Picks up both A and B signals, uses the exisiting VHF antenna and is easy to connect. Picked one up last year (2009) after the Annapolis Show for $415 from Defender. Works well with my E120.


Thanks. Checked the specs; it's a nice unit and it outputs to both a gps/chartplotter and PC. Problem is that it actually costs more than the gx2100 and does less plus I'm purchasing a boat with a very old VHF radio so it may make sense to update it and keep the old one as a backup. Of course, I still haven't figured out how to interconnect the gpsmap 441s, gx2100, and my laptop so guess that's still an outstanding issue.


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## prroots (Nov 13, 2010)

jrd22 said:


> Does the GX2100 just use the existing VHF antenna cable? If so it seems like a no brainer and it says that my RAM mike will connect to it too.


Yes, no need to purchase and install a separate VHF antenna.


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## prroots (Nov 13, 2010)

night0wl said:


> So I'm investigating the newest ACR dual channel nauticast from on sale for sub-$200 at defender. Getting a dedicated whip VHF antennae and mounting it to the bimini. Redundancy of antennas is a good thing anyway, and can't beat the price.


Thanks. That's another option. I do wish it had a VHF antenna splitter built-in so one could share the masthead VHF antenna. The NMEA mux feature is kind of interesting too. Not sure why the gx2100 ended up being a $1000 project. I've seen it for $308, but don't know how much the RAM mics are.
Pete


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## Pau Hana Daz (Oct 28, 2007)

prroots said:


> I've seen it for $308, but don't know how much the RAM mics are.


RAM3 mics are $89.99 at Defender


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## prroots (Nov 13, 2010)

Looks like I found my own answer to post #5. Perhaps it will be of interest to others. Here is the quote:


> NMEA0183 works by having one unit as a talker, and up to three other units as listeners.


This is from this handy reference: NMEA0183 Interfacing - How To Guide - The Hull Truth

It now seems that the gps output from the gpsmap 441s can be paralleled to both the gx2100 and laptop. Also the ais output of gx2100 can be paralleled to both the 441s and laptop. Of course, the laptop would then require a RS232-to-USB converter for each input. Have I understood this correctly? I'm definitely going to bookmark that site for future reference.
Pete


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## eherlihy (Jan 2, 2007)

ActiSense has a GREAT tutorial on NEMA 0183 here; http://www.actisense.com/Downloads/TechTalk/NMEA%200183/The%20NMEA%200183%20Information%20Sheet.pdf


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## CapnBilll (Sep 9, 2006)

I bought the Standard Horizon recently. It was the best purches I've made. It wasn't hard to integrate to chartplotter/GPS. The stock mike has several built in functions.


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## sailingdog (Mar 19, 2006)

prroots said:


> Thanks for all the feedback; food for thought. Can anyone help me with my questions on post #5 or refer me to a NMEA wiring tutorial? My basic question is are NMEA ports strictly point-to-point or is there a way to parallel an output port to more than one external NMEA device? I hope I don't have to buy a multiplexer? Thanks
> Pete


NMEA 0183 is a basically a serial signal and the specification allows for FOUR LISTENER devices for a given SPEAKER DEVICE. That means the AIS NMEA 0183 OUTPUT (SPEAKER) can be connected to your laptop (via an RS-232 port or RS-232-USB adapter), the CHARTPLOTTER and two other devices.


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## night0wl (Mar 20, 2006)

prroots said:


> Not sure why the gx2100 ended up being a $1000 project. I've seen it for $308, but don't know how much the RAM mics are.
> Pete


Reason it became so expensive for me is that on my plotter, I've run out of NMEA ports. The ACR Nauticast has a built in multiplexor, which will relieve me of my port shortage.

MY costs for Matrix were as follows

Radio - $350
RAM Mic - $100
Extension cable - $40 (my helm is too far from nav station)
NMEA Multiplexor $200
Screw hole cable ties - $20
Misc. stainless screws/hardware- $40
Taxes, shippping - $50
Lunch, beer, and dinner for the person helping me out - $100


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## billyruffn (Sep 21, 2004)

night0wl said:


> There are reasons to want receive only...privacy for one! Have you seen those websites that plot ais tracks online? They have prior 30 days of data *OR MORE*!!!! I for one do not want my ais breadcrumbs to be available for all to see.


With a name like NightOwl and concern about who's seeing where he's going, one's gotta wonder if there's not a babe in West Palm that gets a visit now and then from a sailorman who's told his wife he's "Going sailing for the weekend with the guys". 

(Sorry, Owl, couldn't resist!  )


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## arisatx (Sep 2, 2004)

Pete:
Try to get one that is V1.09 or above of the software. When you turn it on, it will display. Prior versions had issues showing Class A targets on some interconnected plotters. I've found after sales support to be very good - I sent mine to the factory, they flashed it to the most recent version for no cost - but you'd save some trouble / time if you got the most recent version from the get-go.


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## prroots (Nov 13, 2010)

eherlihy said:


> ActiSense has a GREAT tutorial on NEMA 0183 here; http://www.actisense.com/Downloads/TechTalk/NMEA%200183/The%20NMEA%200183%20Information%20Sheet.pdf


Thanks. That looks like an excellent reference.
Pete


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## prroots (Nov 13, 2010)

arisatx said:


> Pete:
> Try to get one that is V1.09 or above of the software. When you turn it on, it will display. Prior versions had issues showing Class A targets on some interconnected plotters. I've found after sales support to be very good - I sent mine to the factory, they flashed it to the most recent version for no cost - but you'd save some trouble / time if you got the most recent version from the get-go.


Thanks. Certainly don't want to send a new unit back to factory. When did you purchase yours?
Pete


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## prroots (Nov 13, 2010)

sailingdog said:


> That means the AIS NMEA 0183 OUTPUT (SPEAKER) can be connected to your laptop (via an RS-232 port or RS-232-USB adapter), the CHARTPLOTTER and two other devices.


Thanks. Yes, it appears I can connect the gps output of 441s to both gx2100 and laptop and also connect the ais output of gx2100 to both 441s and laptop. That should provide me redundant ais targets on gx2100, 441s, and laptop. I will also purchase an in-hull transducer for depth on 441s. I would like to share depth info with laptop, but don't know how to do that. Also, can anyone recommend an inexpensive, but reliable RS232-to-USB converter with driver for Windows7? Thanks again
Pete


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## sailingdog (Mar 19, 2006)

prroots said:


> Thanks. Yes, it appears I can connect the gps output of 441s to both gx2100 and laptop and also connect the ais output of gx2100 to both 441s and laptop. That should provide me redundant ais targets on gx2100, 441s, and laptop. I will also purchase an in-hull transducer for depth on 441s. I would like to share depth info with laptop, but don't know how to do that. Also, can anyone recommend an inexpensive, but reliable RS232-to-USB converter with driver for Windows7? Thanks again
> Pete


You will need TWO USB-to-SERIAL converters for the laptop, since the GPS and the AIS will have to be on separate serial ports.


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## prroots (Nov 13, 2010)

sailingdog said:


> You will need TWO USB-to-SERIAL converters for the laptop, since the GPS and the AIS will have to be on separate serial ports.


Yes, that's true.

Can anyone recommend a particular one that includes drivers for Windows 7? I've used them in years past, but many of them didn't update their drivers to work with Windows 7.
Pete


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## arisatx (Sep 2, 2004)

prroots said:


> Thanks. Certainly don't want to send a new unit back to factory. When did you purchase yours?
> Pete


I think Jul 2010. We sent it back in Aug 2010 - quick turnaround.


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## Waltthesalt (Sep 22, 2009)

Consider a transciever. That will have a lot better liklihood that ships will know you're there than your radar blip.


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## zibadun (Mar 19, 2010)

prroots said:


> Thanks for all the feedback; food for thought. Can anyone help me with my questions on post #5 or refer me to a NMEA wiring tutorial? My basic question is are NMEA ports strictly point-to-point or is there a way to parallel an output port to more than one external NMEA device? I hope I don't have to buy a multiplexer? Thanks
> Pete


Pete. 
SH has wiring instructions for Garmin 441.

As far as I know there is no easy way to "split" GX2100 data stream and redirect it to two devices.
(edit: actually I'm wrong. As sailingdog mentioned multiple listeners is possible)

If you already have DSC then you may be better off with a dedicated ais nmea 2000 radio with a splitter, otherwise this radio seems to be a really good deal. My boat has 441s too and I will be adding gx2100. With this setup I will be crossing shipping channels just for the fun of it


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## prroots (Nov 13, 2010)

zibadun said:


> Pete.
> SH has wiring instructions for Garmin 441.


Thanks, I've studied them. They're a bit confusing since it shows that the 441s has both a gps data output and DSC input on port 1. This suggests that input and output can be used for two different signals on the same port. I wondered that if this is true, why can't the AIS signal received on the input of port 2, be re-transmitted on the output of port 2? Or better yet, send out the depth signal since the 441s is also a depth sounder. Apparently this is not possible according to SH.



zibadun said:


> If you already have DSC then you may be better off with a dedicated ais nmea 2000 radio with a splitter


Did you mean to say receiver, not radio here? Why do you say this; is it to take advantage of the NMEA 2000 capability of the 441s? Can you elaborate?



zibadun said:


> My boat has 441s too and I will be adding gx2100. With this setup I will be crossing shipping channels just for the fun of it


I'd look forward to hearing of your progress. Will you also be using a laptop? Do you have the depth transponder? I wish it was possible to output this signal on a NMEA port so the laptop could share it, but apparently there are no more ports available? Thanks again.
Pete


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## prroots (Nov 13, 2010)

arisatx said:


> I think Jul 2010. We sent it back in Aug 2010 - quick turnaround.


Thanks. Hopefully, the ones on the shelves now have been updated, but I'll be sure to check.
Pete


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## rikhall (Feb 7, 2008)

The title of the thread is "Best AIS receiver for the buck". We have, and really like the Smart-Radio-SR161 for $189.00

Smart Radio SR161 AIS Receiver

Rik


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## zibadun (Mar 19, 2010)

prroots said:


> Thanks, I've studied them. They're a bit confusing since it shows that the 441s has both a gps data output and DSC input on port 1. This suggests that input and output can be used for two different signals on the same port. I wondered that if this is true, why can't the AIS signal received on the input of port 2, be re-transmitted on the output of port 2? Or better yet, send out the depth signal since the 441s is also a depth sounder. Apparently this is not possible according to SH.
> 
> Did you mean to say receiver, not radio here? Why do you say this; is it to take advantage of the NMEA 2000 capability of the 441s? Can you elaborate?
> 
> ...


Well I'm confused now  I try to follow the KISS method, which means connect per SH wiring diagram, set and forget. . Tapping into the stream with a computer is an interesting experiment but seems like a lot of trouble. Several serial-USB converters that I've dealt with were very buggy. A lot of them do not have the correct RS-232 voltages and the drivers can crash and/or hang. Something you may not want to deal with while at sea.

I thought you may want a NMEA 2000 AIS receiver or transceiver (are they all "radios"?) if you already have an n2k DSC system that you like.

I have an old depth sounder so I haven't tried to connect a transducer to 441s yet.

I'll buy and set up my gx2100 closer to spring time and will let you know if I run into anything.

Interesting about firmware levels on these, although hard to check when ordering online.


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## prroots (Nov 13, 2010)

rikhall said:


> The title of the thread is "Best AIS receiver for the buck". We have, and really like the Smart-Radio-SR161 for $189.00
> 
> Smart Radio SR161 AIS Receiver
> 
> Rik


Thanks. Looks interesting, but as mentioned, I am looking for an AIS receiver that is:


> NMEA compatible
> Dual channel and
> Includes VHF Splitter


I wish to share the AIS signal between my laptop and gpsmap 441s chart plotter which will require the NMEA compatibility and I'd prefer not to add the complexity and cost of a splitter.
Pete
Pete


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## prroots (Nov 13, 2010)

zibadun said:


> Well I'm confused now  I try to follow the KISS method, which means connect per SH wiring diagram, set and forget. . Tapping into the stream with a computer is an interesting experiment but seems like a lot of trouble. Several serial-USB converters that I've dealt with were very buggy. A lot of them do not have the correct RS-232 voltages and the drivers can crash and/or hang. Something you may not want to deal with while at sea.
> 
> I thought you may want a NMEA 2000 AIS receiver or transceiver (are they all "radios"?) if you already have an n2k DSC system that you like.
> 
> ...


Thanks for the feedback. Actually as mentioned in my original post, the laptop will be my primary device for navigation, not the 441s. The primary purpose of 441s is to provide gps data to the laptop (and gx2100). Since the 441s also has a screen, I might as well use it as a backup chart plotter. As far as RS232-to-USB converters are concerned one does need to be careful to purchase from a reliable, proven source. There are a lot of cheap ones out there that are more trouble than they're worth. Many of them are not certified to work with Vista much less Windows 7. I'm pretty much starting from scratch as far as electronics go. The gx2100 looks like an excellent and cost effective solution. The only negative that I've discovered so far, is that it doesn't support NMEA 2000 and I haven't figured out yet whether that is important. I need to address that issue since I plan to start piecemeal, but hopefully not work myself into a corner when adding additional electronics. As far as tapping into the NMEA signal for laptop is concerned, that is, I've learned, a standard capability of NMEA 0183 and shouldn't introduce a problem as long as I do the wiring in a professional way. I wonder if there's something out there comparable to the gx2100 that offers both NMEA 0183 and 2000? Can anyone explain why I should make NMEA 2000 a requirement in view of the fact that I plan to upgrade electronics in the future. I do want to avoid VHF splitters and multiplexers due to cost and complexity. For example, I may need to add wind or speed sensors in the future. At the moment, I see no reason why NMEA 0183 won't serve my needs.
Pete


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## night0wl (Mar 20, 2006)

rikhall said:


> The title of the thread is "Best AIS receiver for the buck". We have, and really like the Smart-Radio-SR161 for $189.00
> 
> Smart Radio SR161 AIS Receiver
> 
> Rik


Its only a single channel receiver. Why not pay $10 more for the ACR nauticast and get a dual channel receiver with a NMEA MUX built in?


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## prroots (Nov 13, 2010)

I've been communicating with Garmin tech support via email about the 441s so that I can interface the laptop and gx2100 to it in the most effective way. It's like pulling teeth getting them to read my questions and not provide a pat answer to another, perhaps more commonly asked, question! Anyway, here is what I've learned:
1. The wiring diagram from Standard Horizon showing the wiring between gx2100 and 400 series gps (referenced above) is correct
2. The 441s can output both gps and depth data simultaneously on port 1 which can then be distributed in parallel to both gx2100 and laptop
3. The 441s can also receive DSC data from gx2100 on port 1.
4. I can receive hi-speed NMEA AIS data from gx2100 on port 2. According to SH the AIS data can be distributed in parallel to 441s and laptop. 
4. The transmit side of port 2 can't be used for anything (eg, re-transmitting AIS data).

It appears that I can do everything I was hoping to. I still have three outstanding issues that perhaps others can help with:
1. What, if any, reasons are there that would compel me to use NMEA 2000 instead of NMEA 0183? Since I am just starting out, now is the best time to address this issue.
2. What is a recommended USB-to-RS232 converter that includes Windows 7 drivers?
3. What is a good DC-to-DC converter to run laptop off house bank. I know from experience that the switching frequency of most converters interfere with SSB's. Years ago I found a semi-custom one that was specially developed by a ham to minimize this possibility. I have long since lost the info.
Pete


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## sailingdog (Mar 19, 2006)

prroots said:


> I've been communicating with Garmin tech support via email about the 441s so that I can interface the laptop and gx2100 to it in the most effective way. It's like pulling teeth getting them to read my questions and not provide a pat answer to another, perhaps more commonly asked, question! Anyway, here is what I've learned:
> 1. The wiring diagram from Standard Horizon showing the wiring between gx2100 and 400 series gps (referenced above) is correct
> 2. The 441s can output both gps and depth data simultaneously on port 1 which can then be distributed in parallel to both gx2100 and laptop
> 3. The 441s can also receive DSC data from gx2100 on port 1.
> ...


Nothing compels you to use N2K instead of N0183. If you don't have any gear other than the 441 that uses N2K, don't bother. 


> 2. What is a recommended USB-to-RS232 converter that includes Windows 7 drivers?


Most of the Windows Certified ones will work. There are alot that are not certified.  Go with a good name brand, like Keyspan, or IOGear as examples.


> 3. What is a good DC-to-DC converter to run laptop off house bank. I know from experience that the switching frequency of most converters interfere with SSB's. Years ago I found a semi-custom one that was specially developed by a ham to minimize this possibility. I have long since lost the info.
> Pete


You might try using one of the "auto" adapter power supplies, which are designed to allow you to run a laptop off of the 12 VDC power supply in a car. It will have the same voltage range as the house power on a boat for the most part, both being lead-acid 12 VDC systems. iGo, Kensington, etc., all make them and will cover a wide range of brands.


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## prroots (Nov 13, 2010)

sailingdog said:


> You might try using one of the "auto" adapter power supplies, which are designed to allow you to run a laptop off of the 12 VDC power supply in a car. It will have the same voltage range as the house power on a boat for the most part, both being lead-acid 12 VDC systems. iGo, Kensington, etc., all make them and will cover a wide range of brands.


Thanks for the feedback. The problem with virtually all DC-to-DC converters is that they are switching power supplies with a frequency that interferes with the very sensitive front-end of SSB's. Actually, I think hams are probably the best source of information in this area. I'll see if I can find find a good ham forum. Thanks again.
Pete


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## arisatx (Sep 2, 2004)

Pete:

SH has announced a new VHF AIS model, their Matrix 2150

Panbo: The Marine Electronics Weblog: Standard Horizon 2011, new everything!


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## prroots (Nov 13, 2010)

arisatx said:


> Pete:
> 
> SH has announced a new VHF AIS model, their Matrix 2150
> 
> Panbo: The Marine Electronics Weblog: Standard Horizon 2011, new everything!


Thanks! Can anyone summarize what noteworthy features the 2150 includes not provided by the 2100?
Pete


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## zibadun (Mar 19, 2010)

prroots said:


> Thanks! Can anyone summarize what noteworthy features the 2150 includes not provided by the 2100?
> Pete


from what i read the main update is to the NMEA setup so all communication with the chart plotter can happen over just one port. Also 2150 allows selecting True or Magnetic bearing display and may be has a couple of other minor updates.

There is no NMEA 2000 but looks like that is not a big deal. I'd rather have old nmea at a reasonable price than outrageously expensive n2k unit (like garmin 300 VHF AIS which costs at least twice as much)


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## prroots (Nov 13, 2010)

zibadun said:


> from what i read the main update is to the NMEA setup so all communication with the chart plotter can happen over just one port.


I've read what I could find on the gx2150 and still don't understand the significance of the NMEA upgrade. As far as I knew the gx2100 could be interfaced with the Garmin 441s without problems with both gps location and DSC on a single NMEA port. The AIS data from gx2100 to 441s requires a second port, but that seems to remain the same. Does anyone understand exactly how the NMEA has been improved with an example of what benefit it offers? Thanks
Pete


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## arisatx (Sep 2, 2004)

prroots said:


> I've read what I could find on the gx2150 and still don't understand the significance of the NMEA upgrade. As far as I knew the gx2100 could be interfaced with the Garmin 441s without problems with both gps location and DSC on a single NMEA port. The AIS data from gx2100 to 441s requires a second port, but that seems to remain the same. Does anyone understand exactly how the NMEA has been improved with an example of what benefit it offers? Thanks
> Pete


Pete:

Tim Flanagan over at Navagear shares some info here


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## prroots (Nov 13, 2010)

This article attempts to explain the NMEA upgrade a bit better than the reference above:
New Standard Horizon GX2150 VHF/AIS/loudhailer: A winner, for sure

This seems to be the most enlightening part of the above article:


> All the NMEA data between the Matrix unit and whatever chartplotter you might own is aggregated into a single high-speed port.


As I understand it, both the gx2100 and gx2150 have 3 types of NMEA data: gps input, DSC output, and AIS output. Apparently the two outputs can now be combined together by selecting the same Baud rate for each. This was not possible before since DSC out ran at 4800 Baud and AIS at 38400 Baud. Can anyone agree or disagree with this interpretation? Of course, the chartplotter must be capable of interpreting both DSC and AIS on the single NMEA port if my assumptions are true. My guess is that this is a firmware upgrade which did not require a change to hardware. If true, I wonder if it's possible to upgrade existing gx2100's? Looks like I have more questions than answers!
Pete


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## prroots (Nov 13, 2010)

arisatx said:


> Pete:
> 
> Tim Flanagan over at Navagear shares some info here


Looks like we were posting at exactly the same time! That's the same reference I cited above. Thanks
Pete


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## zibadun (Mar 19, 2010)

prroots said:


> As I understand it, both the gx2100 and gx2150 have 3 types of NMEA data: gps input, DSC output, and AIS output. Apparently the two outputs can now be combined together by selecting the same Baud rate for each. This was not possible before since DSC out ran at 4800 Baud and AIS at 38400 Baud. Can anyone agree or disagree with this interpretation? Of course, the chartplotter must be capable of interpreting both DSC and AIS on the single NMEA port if my assumptions are true. My guess is that this is a firmware upgrade which did not require a change to hardware. If true, I wonder if it's possible to upgrade existing gx2100's? Looks like I have more questions than answers!
> Pete


this is my understanding as well - it has a high speed bidirectional COM port which receives gps position and transmits aggregated ais/dsc info.


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## prroots (Nov 13, 2010)

zibadun said:


> this is my understanding as well - it has a high speed bidirectional COM port which receives gps position and transmits aggregated ais/dsc info.


Thanks. The upgrade does not affect me since I had planned to go with the Garmin 441s which has two NMEA ports. Guess it would be a welcome addition to those with older one port chart plotters. I wonder if those older chart plotters can pull both DSC and AIS data off the single port?
Pete


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## TakeFive (Oct 22, 2009)

prroots said:


> Thanks. The upgrade does not affect me since I had planned to go with the Garmin 441s which has two NMEA ports. Guess it would be a welcome addition to those with older one port chart plotters. I wonder if those older chart plotters can pull both DSC and AIS data off the single port?
> Pete


One other case would be people who have a separate depth sounder that they want to feed into the plotter by NMEA. Now you have three inputs (depth, DSC, and AIS) with two available inputs (like with the Garmin 640 that I am considering), so two of them need to be combined.

If the GX2150 multiplexes the two (and I'm not 100% sure it really does due to some of the weasel words in the descriptions), it could make things a lot easier and may avoid the need to buy a multiplexer.


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## TakeFive (Oct 22, 2009)

Some of the questions raised here about the new GX2150 can be answered by looking at the owner's manual. While that would seem obvious, the manual is not easy to find right now. As of this date, there is no mention of the GX2150 on SH's website (despite the fact that they've apparently announced it in press releases), and therefore no link to the new instruction manual - until now.

I did some searching around and experimented with manually editing the URLs of their existing owner's manuals, and sure enough I stumbled across the owner's manual for the new GX2150!

So just click the link if you want advance info on how to configure the DSC to multiplex with AIS at 38,400 baud (page 83) or set true/magnetic COG (page 21), and any of the other new features of this radio.


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## zibadun (Mar 19, 2010)

wow can't hide much from you Doc!  that's great and i hope their webmaster does not get a slap on the hand for making it accessible.

I emailed SH and inquired about availability of 2150 and did not yet get a response. It would be a shame if this model is not shipping by Spring


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## ctj1950 (Oct 17, 2010)

I ordered one from West Marine last week. They said it would be in the first week of February.


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## TakeFive (Oct 22, 2009)

zibadun said:


> ...I emailed SH and inquired about availability of 2150 and did not yet get a response. It would be a shame if this model is not shipping by Spring


Please let us know when you get an answer. I was thinking about calling today to ask the same thing.

When I ordered mine the guy said its official ship date was around Feb. 1, but that the black ones were rumored to be arriving sooner than that (and the white ones later). However, I've never bought from this guy and can't vouch for his reliability.

Since I'm building a homemade nav system around this radio, I'll be toast if it's not in by spring. I'm trying to test all the other components out as they arrive, but several things cannot be tested until I have the radio in place.


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## TakeFive (Oct 22, 2009)

Standard Horizon is now shipping the updated GX2150 VHF/AIS receiver. I received mine yesterday, and the SH website now shows the 2150 in place of the 2100:

Standard Horizon GX2150


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## eherlihy (Jan 2, 2007)

prroots said:


> Thanks! Can anyone summarize what noteworthy features the 2150 includes not provided by the 2100?
> Pete


In a nutshell; this is a HUGE improvement.

I was not a fan of the 2100. Issues for me were AIS receive only, the tiny display, and limited NEMA capability.










The 2100 could only display AIS info on its tiny monochrome display. It could also only accept the slower (4800 baud) NEMA 0183 protocol. Most fixed mount VHF installations are in the saloon at the nav station. Most people sail their boats from the helm. Thus, the display was virtually useless.

The 2150 enables the high speed (38400 baud) NEMA 0183, *AND *it can *SEND *AIS data to your chartplotter. Most chartplotters are installed so as to be visible from the helm. If your chartplotter support AIS, your display will show little arrows representing the ships around you.

While this isn't an AIS Transceiver, it is a *big improvement*!


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## zibadun (Mar 19, 2010)

eherlihy said:


> ... If your chartplotter support AIS, your display will show little arrows representing the ships around you.
> 
> While this isn't an AIS Transceiver, it is a *big improvement*!


No big deal - ships don't always receive Class B transmissions anyway (see Jessica Watson's collision report)

Mine is on the UPS truck. I won't have any more excuses for being ran over by a tanker


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## TakeFive (Oct 22, 2009)

eherlihy said:


> ...The 2100 could only display AIS info on its tiny monochrome display...The 2150 enables the high speed (38400 baud) NEMA 0183, *AND *it can *SEND *AIS data to your chartplotter. Most chartplotters are installed so as to be visible from the helm. If your chartplotter support AIS, your display will show little arrows representing the ships around you...


You're dissing the GX2100 a little more than it deserves. The 2100 does send AIS to a chartplotter at 38400 baud. Its shortcoming is that it insists on receiving GPS sentences at 4800 baud, which makes it incompatible with some older plotters that only provide one port (thus the NMEA in and out must be at the same baud rate). The 2150 can be configured to receive GPS sentences at 38400, so you only need one port on your chartplotter.

In fact, the PC-based Nav system that I am setting up to display AIS data would have worked perfectly fine with the GX2100. However, I'm glad I have the single-port capability in case I add more instrumentation (such as electronic wind gauge) in the future.

Other details comparing the 2150 to the 2100 can be obtained in this PDF file from SH which summarizes all the changes:

http://standardhorizon.com/download... 02.14.11.pdf&FileContentType=application/pdf


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## jackdale (Dec 1, 2008)

As an aside; if you are in cell phone range there is an app for that.

Ais Ship apps - Android

I have loaded up Marine Traffic, but not put it to a test on the water.

The browser versions are even better. Live Ships Map - AIS - Vessel Traffic and Positions

Disclaimer - no financial interest.


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## zibadun (Mar 19, 2010)

jackdale said:


> As an aside; if you are in cell phone range there is an app for that.
> 
> Ais Ship apps - Android
> 
> ...


They are cool sites but I believe they depend on volunteers to provide AIS feeds from local areas. I'd be hesitant to use for navigation .

I've read somewhere about a company with a network of satellites that sniff AIS frequencies on the entire globe and sell access to that huge stream of data. Hopefully not to Somalian pirates


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## TakeFive (Oct 22, 2009)

zibadun said:


> They are cool sites but I believe they depend on volunteers to provide AIS feeds from local areas. I'd be hesitant to use for navigation .


I agree strongly with this.

If you go through the "About" pages of the MarineTraffic.com site, you will see that it does rely on a global network of volunteers for its tracking data. Before ordering the GX2150 I briefly considered using this site instead. I monitored the site daily for awhile (you can bring up icons to show the monitoring stations on the map) and discovered that the monitoring station in my area is down more often than it is up, and as a result there are frequent "blackout" periods when Philly-area commercial traffic disappears. This is absolutely unacceptable for navigational purposes. The best way to get data that you can truly rely on is to install your own AIS receiver or transceiver.


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## Maine Sail (Jan 6, 2003)

eherlihy said:


> The 2150 enables the high speed (38400 baud) NEMA 0183, *AND *it can *SEND *AIS data to your chartplotter. Most chartplotters are installed so as to be visible from the helm. If your chartplotter support AIS, your display will show little arrows representing the ships around you.
> 
> While this isn't an AIS Transceiver, it is a *big improvement*!


I really see little improvement here?

Oh and the 2100 can send AIS data to a plotter just fine mine is at the nav station and the plotter at the helm.

That AIS target is from my Matrix 2100


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## eherlihy (Jan 2, 2007)

First hand experience trumps reading and interpretation every time. MS I defer to you.

That said, my initial impression of this unit was reaffirmed when I read in the document that RythmDoctor points to


> a. GX2100 is able to receive and display GPS data from the chart plotter
> b. GX2100 is able to show AIS targets on the AIS display
> c. Chart Plotter is not able to display AIS targets


I see now that the note is referring to the fact that the GX2100 has a fixed rate (ie Non set-able) COM port. And, that this will limit the use to either receive GPS data (as in the above quote) or display AIS Targets with certain chartplotters (like my Garmin GPSmap 478).

I am _still _waiting for a manufacturer to release an AIS transceiver in a similar package.


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## eherlihy (Jan 2, 2007)

Also - for those of you that _*don't *_want a transceiver, there is an interesting article (?) in the February 2011 Practical-Sailor; Big Brother on the Water, by Ralph Naranjo, that supports your position.


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## TakeFive (Oct 22, 2009)

eherlihy said:


> ...my initial impression of this unit was reaffirmed when I read in the document that RythmDoctor points to
> 
> 
> > a. GX2100 is able to receive and display GPS data from the chart plotter
> ...


I think it is more beneficial to quote the entire context:



> The GX2100 example below shows the connection problem when connected to a plotter with one comport
> Example 1
> a. GX2100 is able to receive and display GPS data from the chart plotter
> b. GX2100 is able to show AIS targets on the AIS display
> ...


From the above, it is obvious that this limitation applies only for those with older plotter that have only one COM port. In that case you need to make a choice, and one of those choices will prevent you from seeing AIS targets on the chart plotter. But the other choice allows you to see the AIS targets on your chart plotter, albeit with some compromises.

For those who have the GX2100 and a one-port chart plotter, you can get the best of both choices by purchasing an inexpensive puck-type GPS (can be found for a little as $30) to feed the GPS coordinates to the GX2100 at 4800 baud. Then you will have:

a. GX2100 is able to receive and display GPS data from the GPS puck
b. GX2100 is able to show AIS targets on the AIS display
c. Chart Plotter is able to display AIS targets

If you already have a GX2100, this is a lot cheaper option than throwing out your radio and buying a 2150. Even though I have a GX2150, I opted to buy an external puck anyway because I wanted a redundant GPS instead of feeding GPS coordinates to the radio from my handheld GPS. I felt it would be more reliable, and very important since GPS coordinates are needed for the DSC/distress button features to work. The external GPS puck is why my configuration would have worked perfectly fine with a GX2100.


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## eherlihy (Jan 2, 2007)

I tried to explain my way around this, but I guess that I should have just posted the image...

Here is Standard Horizon's illustration comparing the NEMA 0183 connection ability between the 2100 and the 2150:









Note that the baud rates for GPS IN and DSC OUT are fixed at 4800, and the AIS OUT is fixed at 38400 on the the GX2100. These baud rates are selectable between 4800, and 38400 on the GX2150.


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## TakeFive (Oct 22, 2009)

Once again, context is important. The graphic you showed applies only to chart plotters with only one COM port. You did not include the line of text explaining that above the graphic. If your chart plotter has two ports, you can make all the needed connections without making a choice between the two.

You might want to re-paste the graphic with the line of text above it.


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## zibadun (Mar 19, 2010)

Installed GX2150 today and connected to the 441s chartplotter. It's very easy - just two wires for the nmea in/out ("common" is the ship's ground) and set both sides to 38k. Works like a charm.


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## prroots (Nov 13, 2010)

zibadun said:


> Installed GX2150 today and connected to the 441s chartplotter. It's very easy - just two wires for the nmea in/out ("common" is the ship's ground) and set both sides to 38k. Works like a charm.


I hope to do the same within the next week or two. Was it a total of 3 wires including ground (ie, NMEA in, NMEA out, and ground)? Have you had a chance to display AIS targets on the 441s? Do you wish the screen of 441s was larger or is it adequate? Do you have plans to use a laptop to plot the same AIS targets as well? My plan is to use the laptop in parallel with 441s.
Pete


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## zibadun (Mar 19, 2010)

prroots said:


> I hope to do the same within the next week or two. Was it a total of 3 wires including ground (ie, NMEA in, NMEA out, and ground)? Have you had a chance to display AIS targets on the 441s? Do you wish the screen of 441s was larger or is it adequate? Do you have plans to use a laptop to plot the same AIS targets as well? My plan is to use the laptop in parallel with 441s.
> Pete


I wish 441s screen was bigger and touch capable.  garmin may have an answer to that (the 720) at $1500. It is not on my list at this point

I used just one twisted pair for nmea in/out (blue and gray wires). On my boat, the gps and the radio share the same ground plane so a separate nmea-common wire isn't really needed. If you think you will have problems with interference or your cable is very long you could use two pairs for this connection (nmea-in+ground and nmea-out+ground) - it would provide better shielding.

note that the brown wire from the radio has a duplicate AIS out stream at 38k. Per manual this can be connected to a pc or to a second chartplotter.


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## prroots (Nov 13, 2010)

zibadun said:


> I wish 441s screen was bigger and touch capable.  garmin may have an answer to that (the 720) at $1500. It is not on my list at this point
> 
> I used just one twisted pair for nmea in/out (blue and gray wires). On my boat, the gps and the radio share the same ground plane so a separate nmea-common wire isn't really needed. If you think you will have problems with interference or your cable is very long you could use two pairs for this connection (nmea-in+ground and nmea-out+ground) - it would provide better shielding.
> 
> note that the brown wire from the radio has a duplicate AIS out stream at 38k. Per manual this can be connected to a pc or to a second chartplotter.


Thanks. I just ordered the gx2150 last night with flush mount kit and RAM mic and will probably order the 441s within the next day or two. I plan to purchase the 441s with its flush mount kit and g2 map for SE Caribbean. Maybe later I'll add the depth transducer for redundancy.
Pete


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## zibadun (Mar 19, 2010)

The RAM mic looks cool. That made me thinking, I can't contact any of the AIS ships easily without leaving the cockpit which is the last thing I want to do when the collision alarm sounds. Scratching my head...


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## prroots (Nov 13, 2010)

zibadun said:


> I used just one twisted pair for nmea in/out (blue and gray wires). On my boat, the gps and the radio share the same ground plane so a separate nmea-common wire isn't really needed. If you think you will have problems with interference or your cable is very long you could use two pairs for this connection (nmea-in+ground and nmea-out+ground) - it would provide better shielding.
> 
> note that the brown wire from the radio has a duplicate AIS out stream at 38k. Per manual this can be connected to a pc or to a second chartplotter.


I purchased my 441s yesterday and will receive my gx2150 via UPS today. I've been studying the manuals of both units. As you know, the gx2150 manual describes two interfacing options depending on whether chartplotter has one or two NMEA ports. You chose the option for one port even though the 441s has two. This seems best since it leaves the brown wire (AIS output) of gx2150 free to connect to my laptop via a USB/serial adapter. I'm wondering why one would ever want to use the two NMEA port option even when interfacing to a chartplotter with 2 ports? The only reason I can see is if chartplotter were restricted to 4800 Baud on the NMEA port communicating gps and dsc info.
Pete


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## TakeFive (Oct 22, 2009)

prroots said:


> I purchased my 441s yesterday and will receive my gx2150 via UPS today. I've been studying the manuals of both units. As you know, the gx2150 manual describes two interfacing options depending on whether chartplotter has one or two NMEA ports. You chose the option for one port even though the 441s has two. This seems best since it leaves the brown wire (AIS output) of gx2150 free to connect to my laptop via a USB/serial adapter. I'm wondering why one would ever want to use the two NMEA port option even when interfacing to a chartplotter with 2 ports? The only reason I can see is if chartplotter were restricted to 4800 Baud on the NMEA port communicating gps and dsc info.
> Pete


Remember that each NMEA port allows only one talker, but up to 3 listeners. So you may not even need the brown wire for your laptop. Just split your gray wire and send it to both chartplotter and laptop. If your laptop software is somehow confused by mulitplexing the AIS with DSC sentences together, then you should use the brown wire because it will send AIS only without the DSC.

There are many reasons why SH kept the 4800 baud 2-port mode. The most common one that I can think of is where one device (like a GPS) talks to the radio and another listener. If that other listener only accepts 4800 baud NMEA, then the radio would also have to be configured to listen at 4800 baud. There are other situations where 2-port mode could eliminate the need for multiplexers or baud converters.


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## prroots (Nov 13, 2010)

Our new-to-us 2001 Beneteau 411 came with Raymarine instruments including a ST60 Multi unit. It has unused NMEA input and output ports. If I connect the output of 441s to it, I wonder if it will report route info such as distance to waypoint, XTE, etc? I do know that the Raymarine chartplotter that we're replacing provided this info via SeaTalk to the Multi whenever a route was active.

Edit: tried connecting output of 441s (port 2/NMEA 4800) to NMEA input of Raymarine Multi unit. It works great! Initially, I had tried connecting 441s port 1, but it's configured as high speed (38400) and apparently Multi can't handle it.
Pete


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## prroots (Nov 13, 2010)

As mentioned above, I'm able to provide gps data to my Raymarine SeaTalk network over port 1 at 4800 Baud. However, for some reason the 441s isn't reading anything back from the Raymarine SeaTalk network such as water temp, rudder position, depth, etc. Any ideas what could be wrong?
Pete


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## zibadun (Mar 19, 2010)

I don't recall 441s supporting the SeaTalk protocol. do you need something like E85001 converter?


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## prroots (Nov 13, 2010)

zibadun said:


> I don't recall 441s supporting the SeaTalk protocol. do you need something like E85001 converter?


As mentioned, the ST60 Multi unit offers a NMEA 0183 input and output port (separate from SeaTalk). We've already got the NMEA input port working since the unit displays navigation information sent from the 441s. That proves we're using the correct NMEA profile and speed, etc.
Pete


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## prroots (Nov 13, 2010)

Can anyone mention make and model of USB to serial converters that they are using with Windows 7? Thanks
Pete


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## obarut (Oct 23, 2008)

prroots said:


> Can anyone mention make and model of USB to serial converters that they are using with Windows 7? Thanks
> Pete


I bought from Welcome to Milltech Marine - your AIS experts a "Sabrent USB 2.0 to (9-pin) Serial DB9 RS-232 Adapter, 6-ft. Adapter Cable, Includes Drivers for Windows 7, Vista, XP and MAC OS " for my SR161 AIS receiver.


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## prroots (Nov 13, 2010)

obarut said:


> I bought from Welcome to Milltech Marine - your AIS experts a "Sabrent USB 2.0 to (9-pin) Serial DB9 RS-232 Adapter, 6-ft. Adapter Cable, Includes Drivers for Windows 7, Vista, XP and MAC OS " for my SR161 AIS receiver.


Thanks. How has it performed? Any dropouts? It looks like it's this:


> Sabrent USB to Serial Adapter - FTDI Edition Item Id: SBT-USC6K-FTDI


Is that the one? The price is right.
Pete


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## obarut (Oct 23, 2008)

prroots said:


> Thanks. How has it performed? Any dropouts? It looks like it's this: Is that the one? The price is right.
> Pete


Yes the item is it. The price is the same. Unfortunately I haven't test the USB connection yet. But the AIS is working good with my GARMIN 3005C chartplotter.


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## zibadun (Mar 19, 2010)

obarut said:


> I bought from Welcome to Milltech Marine - your AIS experts a "Sabrent USB 2.0 to (9-pin) Serial DB9 RS-232 Adapter, 6-ft. Adapter Cable, Includes Drivers for Windows 7, Vista, XP and MAC OS " for my SR161 AIS receiver.


The ones with FTDI chip is the way to go because Win7 has good drivers. Different kinds usually end up crashing. FTDI are also on ebay for about $5 incl. shipping


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## prroots (Nov 13, 2010)

obarut said:


> Yes the item is it. The price is the same. Unfortunately I haven't test the USB connection yet. But the AIS is working good with my GARMIN 3005C chartplotter.


Thanks


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## r.furborough (May 28, 2006)

*AIS Receivers*



rikhall said:


> The title of the thread is "Best AIS receiver for the buck". We have, and really like the Smart-Radio-SR161 for $189.00
> 
> Smart Radio SR161 AIS Receiver
> 
> Rik


I agree this is a great price for an AIS receiver, unfortunately it can only interface to a computer not a chart plotter. For integration with a boats chart plotter the Si-Tex Marine Electronics AIS Black Box at a list price of$289.00 is a good buy, it will probably be cheaper through the usual channels.


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## obarut (Oct 23, 2008)

r.furborough said:


> I agree this is a great price for an AIS receiver, unfortunately it can only interface to a computer not a chart plotter. For integration with a boats chart plotter the Si-Tex Marine Electronics AIS Black Box at $289.00 is a good buy.


I doubt that it is true. Because I bought SR-161 and connected it to GARMIN 3005C chartplotter. It works very well. Here is the proof:


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## TakeFive (Oct 22, 2009)

The issue here is whether NMEA 0183 transmissions need to strictly adhere to RS422 protocols or you can get away with RS232. RS422 has dedicated (+) and (-) wires for each port, resulting in much lower electrical noise when using twisted pair wiring over long runs. RS232 uses a common ground, so you only need one (+) wire for each port. Apparently many Garmin devices have common ground, so they don't strictly adhere to the RS422 requirement anyway.

Click here for a good explanation of all of this.

From the web description, it looks like the SR161 uses a common ground for the GPS input and AIS output, which is the reason they caution about its use with some chartplotters. If your chartplotter has only one ground wire (or multiple ground wires that have continuity with each other when tested with an ohmmeter), it's not RS422 anyway, and the SR161 should work. If your chartplotter has (+) and (-) wires for each port, you may do best with a true RS422 device, although you could try it and see (at your own risk - I explicitly disavow any liability for damage to your equipment). Apparently some people get by with common ground connections on the RS422 devices, though Smart Radio does not want to guarantee it (neither do I).

FYI, the popular GX2100/2150 VHF/AIS receivers use a single common ground (thus RS232 protocol), so they are subject to the same issues as the SR161, but Standard Horizon does not seem to provide any dire warnings about compatibility with RS422 chartplotters.

A separate concern that I would have with the SR161 is that it is only single channel, so it has to scan to pick up Class A and Class B transmissions. As AIS Class B transmissions become more numerous among pleasure vessels, the need to scan two different channels may lead to missed transmissions. The GX2100/2150 has a dual-channel AIS receiver, so it should be more reliable in high traffic areas.

The GX2100/2150 also eliminates the need for a second antenna, or for a splitter on a single antenna.



r.furborough said:


> I agree this is a great price for an AIS receiver, unfortunately it can only interface to a computer not a chart plotter. For integration with a boats chart plotter the Si-Tex Marine Electronics AIS Black Box at a list price of$289.00 is a good buy, it will probably be cheaper through the usual channels.


Since the Si-Tex uses a RS232 DB9 connector for input and output, it would have the same communications limitations as the SR161 and the GX2150. I see no benefit to its higher price, unless it is true dual channel instead of scanning (which the online specs do not show).


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## prroots (Nov 13, 2010)

zibadun said:


> The ones with FTDI chip is the way to go because Win7 has good drivers. Different kinds usually end up crashing. FTDI are also on ebay for about $5 incl. shipping


Thanks. Before I saw this, I bought two USB/serial adapters from West Marine made by Garmin. My rationale is that they were compatible with Garmin products and hopefully Windows 7. So far they seem OK, but they tend to interfere with the mouse (both touchpad and USB mouse). The drivers seem to be by MCT. The CD that came with it has drivers for 98, 2000, and XP; nothing newer. Windows 7 did install the drivers automatically so guess this is not too important. Any ideas how good or bad these adapters are? I can always return them if necessary.

Edit: how do I locate one on eBay for that price that uses the FTDI chip? If I search on FTDI the prices start at around $16 including shipping.
Pete


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## r.furborough (May 28, 2006)

*Best AIS Receiver for the Buck*



RhythmDoctor said:


> Since the Si-Tex uses a RS232 DB9 connector for input and output, it would have the same communications limitations as the SR161 and the GX2150. I see no benefit to its higher price, unless it is true dual channel instead of scanning (which the online specs do not show).


The SiTex unit, although it has a DB9 connector does not adhere to RS423 connectivity at the connector and is capable of supporting 4800 baud in for GPS position data on pin 9 and 38,400 baud in and out on pins 2 and 3 whereas the the SR161 has only 38,400 on pins 2 and 3 and requires a separate GPS antenna for position data.

The reference to the GX2150 communications limitations is also incorrect, the GX2150 support switchable baud rates something the GX2100 couldn't support and as such required a multiplexer for the connectivity to certain chart plotters to support the DSC function of the radio.


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## zibadun (Mar 19, 2010)

prroots said:


> Edit: how do I locate one on eBay for that price that uses the FTDI chip? If I search on FTDI the prices start at around $16 including shipping.
> Pete


for example item # 140310582386 . it does not say in the description about ftdi, but that's the one. i bought two from this seller.

it's so cheap that you might want to give a try. there should not be any interference with other devices.


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## r.furborough (May 28, 2006)

obarut said:


> I doubt that it is true. Because I bought SR-161 and connected it to GARMIN 3005C chartplotter. It works very well. Here is the proof:


Acknowledged, I overlooked the fact that you can wire an RS232 connector as RS422 to support NMEA0183 connectivity, this is something that Milltech omit in their literature for the SR-161, they tend to favor advertising their compatibility with PC charting programs.


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## TakeFive (Oct 22, 2009)

prroots said:


> Thanks. Before I saw this, I bought two USB/serial adapters from West Marine made by Garmin. My rationale is that they were compatible with Garmin products and hopefully Windows 7. So far they seem OK, but they tend to interfere with the mouse (both touchpad and USB mouse)...


This problem is not caused by your USB/serial adapters. It is caused by 0183 NMEA sentences of any GPS device. The best place to find a concise description of this problem, and a straightforward solution to it, is Appendix D of the instructions for Garmin's 18x GPS (click here for PDF). Unfortunately these instructions are copy protected, so I cannot copy/paste it here. But the instructions say that this problem is true for ALL NMEA 0183 devices.


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## prroots (Nov 13, 2010)

zibadun said:


> for example item # 140310582386 . it does not say in the description about ftdi, but that's the one. i bought two from this seller.
> 
> it's so cheap that you might want to give a try. there should not be any interference with other devices.


Thanks a lot. I just ordered two. At that price, I can't go wrong 
Pete


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## DoubleEnder (Mar 8, 2011)

Question! The GX2150 looks like an awesome piece. Will there be any problems interfacing it with a Garmen GPSMap 3206? 

Thanks for any input.

Brian


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## prroots (Nov 13, 2010)

DoubleEnder said:


> Question! The GX2150 looks like an awesome piece. Will there be any problems interfacing it with a Garmen GPSMap 3206?
> 
> Thanks for any input.
> 
> Brian


Don't know that particular unit, but if it has a NMEA 0183 hi speed port, it should work fine. I just interfaced my gpsmap 441s to it using that port with the 441s NMEA input reading ais data and the 441s NMEA output providing position data to the radio. Basically, it's 3 wires: input, output, and common. Note: I believe it will work at standard speed too, but haven't tested that.
Pete


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## prroots (Nov 13, 2010)

RhythmDoctor said:


> This problem is not caused by your USB/serial adapters. It is caused by 0183 NMEA sentences of any GPS device. The best place to find a concise description of this problem, and a straightforward solution to it, is Appendix D of the instructions for Garmin's 18x GPS (click here for PDF). Unfortunately these instructions are copy protected, so I cannot copy/paste it here. But the instructions say that this problem is true for ALL NMEA 0183 devices.


Interesting. I had no idea what you meant until I read Appendix D of the quoted reference
Pete


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## prroots (Nov 13, 2010)

RhythmDoctor said:


> This problem is not caused by your USB/serial adapters. It is caused by 0183 NMEA sentences of any GPS device. The best place to find a concise description of this problem, and a straightforward solution to it, is Appendix D of the instructions for Garmin's 18x GPS (click here for PDF). Unfortunately these instructions are copy protected, so I cannot copy/paste it here. But the instructions say that this problem is true for ALL NMEA 0183 devices.


I have reviewed Appendix D and none of the solutions are applicable and/or desirable in my circumstance. For example, I don't have the Microsoft Serial Ballpoint mouse referenced. Anyone find a good solution to this problem that doesn't require booting up and connecting things in a certain order?
Pete


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## TakeFive (Oct 22, 2009)

prroots said:


> I have reviewed Appendix D and none of the solutions are applicable and/or desirable in my circumstance. For example, I don't have the Microsoft Serial Ballpoint mouse referenced. Anyone find a good solution to this problem that doesn't require booting up and connecting things in a certain order?
> Pete


I am not sure why "Solution 1" is not acceptable to you. Under XP, the Serial Ballpoint Mouse shows up in Device Manager whether you have one or not. (Maybe Windows 7 doesn't have this?) So if it's there, there's no reason NOT to disable it (unless you're one of the very few who has that exact model mouse). Once you do that the problem is fixed. You might have to reboot once to make it effective (I can't remember), but it's a one-time permanent fix. There is no need to connect things in a certain order when you use this method.

The problem is that some NMEA GPS sentences translate into binary bit streams that are identical to the signal a Serial Ballpoint Mouse sends to a COM port. When your computer sees that bit stream, it instantaneously move your mouse to another location on the screen. So you need to find a way to block Windows from interpreting those sentences incorrectly. Good luck finding another way - I suspect Garmin's solutions are pretty comprehensive.

As you may be aware from the OpenCPN forum, I have had a separate serial problem that I finally figured out a workaround. You could consider asking over there. But be forewarned that their most recent response to me was that I should consider switching to Linux, since OpenCPN works better on that platform.


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## prroots (Nov 13, 2010)

RhythmDoctor said:


> I am not sure why "Solution 1" is not acceptable to you. Under XP, the Serial Ballpoint Mouse shows up in Device Manager whether you have one or not. (Maybe Windows 7 doesn't have this?)


It doesn't show up in my Windows 7. Under mice, I list only Synaptics PS/2 Port Pointing device and Microsoft USB Wireless Mouse (Intellipoint). The former one is the built-in touchpad and the latter one is the mouse I've added.
Pete


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## PCP (Dec 1, 2004)

Does anybody have impute on the new Navicom VHF radio?

They offer AIS as well as a second station at a very good price.

Navicom Radio VHF RT 650 with DSC [091.RT650] - € 350.00 :


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## TakeFive (Oct 22, 2009)

prroots said:


> It doesn't show up in my Windows 7. Under mice, I list only Synaptics PS/2 Port Pointing device and Microsoft USB Wireless Mouse (Intellipoint). The former one is the built-in touchpad and the latter one is the mouse I've added.
> Pete


Hmm, never used Win7. If you like living dangerously, you might search the HKCU section of the registry for "Ballpoint". If you see it with a value of "1", change to "0". (Backup first, of course.)

Otherwise, call Garmin tech support. The problem is so pervasive that they must have a fix for Win7.

BTW, I did have this problem until I disabled Ballpoint Mouse. I'm speaking from exoerience, not from Internet folklore. ;-)


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## wordsort (Feb 17, 2011)

It looks like the GX 2150 will not output GPS data as well as AIS. Is that correct? It would be nice if I could use my old, (otherwise pretty useless chartplotter) as a GPS receiver which sends GPS data to the GX 2150 which would then send it on to my PC along with the AIS. But it seems like this won't work and I will need a separate GPS receiver for my PC. Am I right about that? Sorry if this has already been discussed.


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## prroots (Nov 13, 2010)

wordsort said:


> It looks like the GX 2150 will not output GPS data as well as AIS. Is that correct? It would be nice if I could use my old, (otherwise pretty useless chartplotter) as a GPS receiver which sends GPS data to the GX 2150 which would then send it on to my PC along with the AIS. But it seems like this won't work and I will need a separate GPS receiver for my PC. Am I right about that? Sorry if this has already been discussed.


You're right that the gx2150 won't output gps data, but that's not a problem. The chartplotter can output gps data to both the gx2150 and a USB/serial converter which in turn supplies the PC. That assumes you don't have any serial ports on your PC. As an example, my 441s chartplotter outputs gps data to my Raymarine network, gx2150, and laptop (via USB/serial converter).
Pete


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## rikhall (Feb 7, 2008)

r.furborough said:


> I agree this is a great price for an AIS receiver, unfortunately it can only interface to a computer not a chart plotter. For integration with a boats chart plotter the Si-Tex Marine Electronics AIS Black Box at a list price of$289.00 is a good buy, it will probably be cheaper through the usual channels.


Sorry, I am not sure why it does not integrate to yours, it does integrate to my Garmin 440.

Used it all the way from Annapolis to Fredericton, NB, Canada. I also had simultaneous data on my laptop running FUGAWI ENC.

Rik


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## TakeFive (Oct 22, 2009)

wordsort said:


> It looks like the GX 2150 will not output GPS data as well as AIS. Is that correct? It would be nice if I could use my old, (otherwise pretty useless chartplotter) as a GPS receiver which sends GPS data to the GX 2150 which would then send it on to my PC along with the AIS. But it seems like this won't work and I will need a separate GPS receiver for my PC. Am I right about that? Sorry if this has already been discussed.


Yes, remember that NMEA 0183 is "multiple listener, one talker." You can split the NMEA output of any single device without a repeater or multiplexer (typically up to three ways, but YMMV based on the impedance of the receiving devices, electrical noise in your boat, length of run, etc). So your old chartplotter could feed both the AIS and your PC with GPS data. But you'll need at least two inputs on your PC - one for AIS (@38400 baud) and a second one for GPS (presumably @4800 baud, since it's an old chartplotter). If you only have USB, you'll need a separate serial/USB adapter for each (I used serial/Bluetooth to make it all wireless). If you have only one USB input on your computer, an inexpensive USB HUB should work (but I've never actually tried this).


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## wordsort (Feb 17, 2011)

I was hoping that the 2150 would send both GPS and AIS so I could use just one serial/Bluetooth. I think the beast solution is probably to get a separate bluetooth GPS receiver and then sell the Chartplotter for what I can get. Anyway it sounds great to be able to get AIS from the GX 2150 for almost the same price as a stand alone AIS receiver. I get the rest of the radio for free basically.


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## TakeFive (Oct 22, 2009)

wordsort said:


> I was hoping that the 2150 would send both GPS and AIS so I could use just one serial/Bluetooth. I think the beast solution is probably to get a separate bluetooth GPS receiver and then sell the Chartplotter for what I can get. Anyway it sounds great to be able to get AIS from the GX 2150 for almost the same price as a stand alone AIS receiver. I get the rest of the radio for free basically.


I had a similar decision and came close to doing what you were doing. But then I realized that having the computer pick up GPS via Bluetooth and then send it to the radio meant that the radio would only get GPS coordinates when the computer was on. If the computer crashed, battery ran low, or other computer failure, the AIS and DSC would not work on the radio. I considered GPS coordinates to the radio to be critical for safety reasons so I bought a dedicated GPS puck to feed NMEA directly to the radio. I opted for the Garmin 18x LVC. It seems you old chartplotter would meet this need quite nicely.

Click here to see a thread that covers my setup. It is very similar to what you are considering.


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## TakeFive (Oct 22, 2009)

r.furborough said:


> The reference to the GX2150 communications limitations is also incorrect, the GX2150 support switchable baud rates something the GX2100 couldn't support and as such required a multiplexer for the connectivity to certain chart plotters to support the DSC function of the radio.


No, my statement was correct. The limitation that I was referring to was the use of a common ground (thus RS232, not RS422), which applies to both the GX2100 and GX2150. I thought that was clear from the context of my response.

You still didn't answer whether the Si-Tex is true dual channel or scanning. That could be an even more important differentiator between it and the SR161.


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## wordsort (Feb 17, 2011)

Hmmm, I was thinking that Radio didn't really need GPS for anything crushingly important, but I guess it does for many of its nice features that I really want, like the collision alarm. Tell me this, is there a GPS receiver that I can get that will connect directly to the radio and at the same time send data to the PC via bluetooth? That would save me getting two GPS receivers.


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## r.furborough (May 28, 2006)

RhythmDoctor said:


> You still didn't answer whether the Si-Tex is true dual channel or scanning. That could be an even more important differentiator between it and the SR161.


The SiTex is the same unit as the Nasa Marine unit, it 'switches' (read scans)between channels according to Nasa's specification.


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## TakeFive (Oct 22, 2009)

wordsort said:


> Hmmm, I was thinking that Radio didn't really need GPS for anything crushingly important, but I guess it does for many of its nice features that I really want, like the collision alarm. Tell me this, is there a GPS receiver that I can get that will connect directly to the radio and at the same time send data to the PC via bluetooth? That would save me getting two GPS receivers.


As mentioned already, NMEA 0183 is multiple talker, one listener, so you can just splice the GPS output to the two devices. This is supposed to be true for all NMEA GPS devices. I told you which one I used. You will want to wire your computer so that it is able to talk to the GPS for configuration purposes. See my link for info on how I did it.


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## prroots (Nov 13, 2010)

RhythmDoctor said:


> Hmm, never used Win7. If you like living dangerously, you might search the HKCU section of the registry for "Ballpoint". If you see it with a value of "1", change to "0". (Backup first, of course.)
> 
> Otherwise, call Garmin tech support. The problem is so pervasive that they must have a fix for Win7.
> 
> BTW, I did have this problem until I disabled Ballpoint Mouse. I'm speaking from exoerience, not from Internet folklore. ;-)


Thanks. I've searched in the registry without luck. I've now written a support email to Garmin. I find that works better than calling them in terms of the quality of response.
Pete


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## prroots (Nov 13, 2010)

RhythmDoctor said:


> This problem is not caused by your USB/serial adapters. It is caused by 0183 NMEA sentences of any GPS device. The best place to find a concise description of this problem, and a straightforward solution to it, is Appendix D of the instructions for Garmin's 18x GPS (click here for PDF). Unfortunately these instructions are copy protected, so I cannot copy/paste it here. But the instructions say that this problem is true for ALL NMEA 0183 devices.


As mentioned, the solutions proposed in Appendix D did not solve my problem on Windows 7. I did get a response from Garmin who have identified this as a Windows 7 bug. They offer these links to resolve the problem on Windows 7:
Window7 incorrectly identified serial GPS as Serial Mouse - Microsoft Answers

Windows 7 recognized USB GPS as a serial Mouse in Windows 7 - Microsoft Answers

I followed the solution offered in the second link and so far it's working. 
Pete


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## TakeFive (Oct 22, 2009)

prroots said:


> As mentioned, the solutions proposed in Appendix D did not solve my problem on Windows 7. I did get a response from Garmin who have identified this as a Windows 7 bug. They offer these links to resolve the problem on Windows 7:
> Window7 incorrectly identified serial GPS as Serial Mouse - Microsoft Answers
> 
> Windows 7 recognized USB GPS as a serial Mouse in Windows 7 - Microsoft Answers
> ...


It sounds like it is the exact same issue as with Windows XP. Until someone proves it's something else, I'll stick with my hypothesis about the GPS sending a bit stream that's sometimes identical to a mouse, which isn't really a "bug" in the OS. The OS does not have any magic ability to identify the device, other than interpreting 010001111010010100010101's that the device sends.

The only difference here is that you have to edit the registry to turn it off in Win7 - also similar to what I had already suggested.

I'm glad I shared my experience with you. You could have wasted a lot of time experimenting with different USB adapters.


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## jackdale (Dec 1, 2008)

RhythmDoctor said:


> It sounds like it is the exact same issue as with Windows XP. Until someone proves it's something else, I'll stick with my hypothesis about the GPS sending a bit stream that's sometimes identical to a mouse, which isn't really a "bug" in the OS. The OS does not have any magic ability to identify the device, other than interpreting 010001111010010100010101's that the device sends.
> 
> The only difference here is that you have to edit the registry to turn it off in Win7 - also similar to what I had already suggested.
> 
> I'm glad I shared my experience with you. You could have wasted a lot of time experimenting with different USB adapters.


 I do not use a mouse when using my GPS; not enough USB ports. (Win XP)


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## prroots (Nov 13, 2010)

RhythmDoctor said:


> It sounds like it is the exact same issue as with Windows XP. Until someone proves it's something else, I'll stick with my hypothesis about the GPS sending a bit stream that's sometimes identical to a mouse, which isn't really a "bug" in the OS. The OS does not have any magic ability to identify the device, other than interpreting 010001111010010100010101's that the device sends.
> 
> The only difference here is that you have to edit the registry to turn it off in Win7 - also similar to what I had already suggested.
> 
> I'm glad I shared my experience with you. You could have wasted a lot of time experimenting with different USB adapters.


Yes, according to Garmin it is the same issue, however, the difference with Windows 7 is that the device doesn't stay in the device manager long enough to be disabled. I'm sorry if it sounded like I was dismissing your original post; it certainly pointed me in the right direction. I'm merely making the case that Windows 7 is different than XP.

Garmin does make a good case that this is a Windows bug. It is entirely possible for the OS to distinguish between the mouse and the USB/serial converter. The output has a similarity, but certainly not indistinguishable. Given your intereest I'll paste an excerpt of the email received from Garmin:


> I do not have Windows 7 available to try the fixes suggested there. What astounds me is that Microsoft insists on continuing to write this bug into every new version of Windows that they release, but they do so in a manner that makes all previous means to solve the problem ineffective! They have known about this bug in their operating system at least since 1995 when I first contacted them about it. Every time I began to make progress with someone that was trying to ensure that this is not an issue in future versions of Windows, the person with whom I was discussing the issue would suddenly become unavailable or unresponsive to me. After trying for nearly 5 years to work with Microsoft to ensure that this bug is not written into new versions of Windows, I finally gave up trying to get them to do the right thing and quit assuming that every serial device that sends the $ character must be a Ballpoint Serial Mouse. There are also robotic command sets that begin every command line with the $ character, so those types of systems also have this issue.


Edit: the latest fix referenced above does not work with my Windows 7 laptop. The only workaround that may work so far is to carefully sequence the startup of equipment so that Windows doesn't get confused 
Pete


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## prroots (Nov 13, 2010)

jackdale said:


> I do not use a mouse when using my GPS; not enough USB ports. (Win XP)


The problem does not depend on whether you happen to be using a mouse or not. The OS thinks the USB/serial adapter is a mouse and starts moving the cursor and making clicks based upon NMEA data being sent by the gps, etc.
Pete


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## scraph (Oct 19, 2009)

As a point of order, I would not rely to AIS to prevent collisions at sea. Unfortunately, despite requirements to the contrary, not all vessels are transmitting AIS. Further, not all ships required to post a look-out, or monitor VHF, will actually be doing so at all times. If collision avoidance is your ultimate desire I'd recommend radar (with both range and CPA alarms) and an experienced look-out who can recognize and continually evaluate risks of collision (ie. CBDR, 0 angle off the bow, lead line of sight, etc).

Keep in mind, keeping a constant look-out does not require someone to always be topside with binoculars. If you estimate your own height of eye at 8 feet above the water then the horizon is ~3.5 nm away. The masthead height of a standard ocean tanker can be estimated at about 120ft (horizon distance of ~13nm). That being said you should be able to see an ocean tanker at a maximum range of ~16nm (visibility supporting, of course). If you estimate their cruising speed at 12kts (a fair assumption) and yours at 6kts then checking the horizon every 45minutes will leave you 2.5nm worst case (worst case being that they became visible the moment you went below and they are headed directly towards you and you towards them). If you come topside at 2.5nm and turn 90 degrees off their course then you will still have a CPA of 1.25 nm.

I suppose that is a long way of saying ... on open ocean ... have someone sweep the horizon every 45 minutes instead of vegging down below waiting for AIS to alarm. The sort of collision avoidance I described works.

Nearshore, you need to change the look-out interval based on shorter masthead heights of expected traffic (ie 50 ft for small freighters, 70 ft for coastal tankers) ... but you should be on near constant look-out during coastal piloting anyways.

I know this discussion is off the wall for a request of 'best AIS receiver for the buck' but I hope it will help with the larger question of collision avoidance.


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## scraph (Oct 19, 2009)

Sorry if I'm using jargon without defining it.

CPA = closest point of approach
CBDR = constant bearing, decreasing range
0 angle off the bow = the vessel of concern is pointed directly towards you
lead line of sight = both your vessel and the vessel of concern are driving in the same general direction (ie you will see the starboard side of the other vessel and they bear somewhere off to your port)

Best wishes. Please don't let technology substitute good practices.


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## prroots (Nov 13, 2010)

As mentioned above, the referenced Windows 7 fix does not work for me. So far the only thing that seems to work is to sequence my equipment on in a particular order as follows:

Boot laptop with USB/serial converters connected
Start OpenCPN navigation program
Power up VHF radio and gps

This sequence ensures that the adapters are recognized by Windows prior to receiving any NMEA data sentences (in step 3 above). I would be interested in hearing experiences from other Windows 7 users who have USB/serial converters.
Pete


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## prroots (Nov 13, 2010)

zibadun said:


> for example item # 140310582386 . it does not say in the description about ftdi, but that's the one. i bought two from this seller.
> 
> it's so cheap that you might want to give a try. there should not be any interference with other devices.


I received mine today based upon that item number. Turns out the chips are by Prolific. I wonder how one gets the ftdi chips? Anyways, the good news is that once Windows 7 got confused by the NMEA sentences, I noted for the first time the appearance of the Microsoft Serial Ballpoint mouse. This never appeared while using the Garmin USB/serial adapters with an MCT chip. I immediately disabled it and so far, the problem has not reappeared. I am sure that Windows treats the MCT and Prolific chips differently because I had searched on 'ballpoint' in the registry before and it never appeared. Now with the Prolific chips it does. My conclusion is that even though the problem is caused by a Windows 7 bug, the nature of the problem and the ease with which one finds a workaround is affected by the chip of the USB/serial adapter. Since the ftdi chip uses a Microsoft driver as you state, I wonder if the problem would ever appear?
Pete


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## prroots (Nov 13, 2010)

Just crossed the Gulf Stream last night. This was the first opportunity we had to test AIS under realistic conditions. Our Standard Horizon gx2150 in combination with Garmin 441s worked like a charm. Our laptop running OpenCPN with input from both VHF and Garmin also worked well. The USB-to-serial converters (referenced above) also have performed wonderfully under Windows 7.

The only problem we've had is not being able to find Explorer charts of the Bahamas that run under Windows 7 with OpenCPN. The 441s comes with them built-in.
Pete


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## NICHOLSON58 (Feb 22, 2009)

Look at VESPER MARINE 850 Watchmate. Its not cheap but is totally stand alone, class B transponder, NMEA, built in GPS, alarm. It will run and anchor watch without any other devices running and is the lowest power suck of all I looked at. It has stealth mode (receive only). It also has filtering to ignore non-threat targets in busy harbors. Hook to a VHS antenna or share with their splitter. I think the power may be as low as 3 watt so you can run it when everything else is off without much penalty.


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## NICHOLSON58 (Feb 22, 2009)

By the way, I also have a SH2100. It needs an external GPS antenna. THe maker assumes you will use the GPS signal on your 183 network but I prefer to let all devices function independantly for discretionary power conservation and for total reliability. Can anyone suggest a reasonable price GPS antenna that can be powered from 12 VDC? I thought of using one from the BU-353 people as i have in my PC for SeaClear but all of theirs are 5 volts.


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## TakeFive (Oct 22, 2009)

NICHOLSON58 said:


> By the way, I also have a SH2100. It needs an external GPS antenna. THe maker assumes you will use the GPS signal on your 183 network but I prefer to let all devices function independantly for discretionary power conservation and for total reliability. Can anyone suggest a reasonable price GPS antenna that can be powered from 12 VDC? I thought of using one from the BU-353 people as i have in my PC for SeaClear but all of theirs are 5 volts.


The easiest way to convert 12v to 5v is to tap a 12v adapter onto the wire, insert one of those tiny USB chargers, and chop a USB cable in half and get the 5v off the power leads. That's what I did to power my puck and Bluetooth transmitters.

I think the USB standard is 500 mA, which is enough to power any GPS antenna (with amperage to spare for Bluetooth transmitters). However the wires are not marine grade, so you'll have to inspect annually and replace if needed. I'm in a freshwater environment, so it works fine for me.


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## NICHOLSON58 (Feb 22, 2009)

Thanks. I'm not sure, but I think that system uses a dropping resister/splitter to sap 5 from 12. If so, that would make it inefficient. Not a problem mayby if you are on shore power regularly but for off-shore I'd need to check out the power.


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## TakeFive (Oct 22, 2009)

NICHOLSON58 said:


> Thanks. I'm not sure, but I think that system uses a dropping resister/splitter to sap 5 from 12. If so, that would make it inefficient. Not a problem mayby if you are on shore power regularly but for off-shore I'd need to check out the power.


Originally I was going to use this, but IIRC I saw some videos on YouTube where someone disassembled a cheapo USB adapter and it had the same voltage regulator inside. I'm not sure whether the Radio Shack regulator is just a dropping resistor or not. I do realize that if that's all it does, then you're wasting at least 7/12 of the power as heat.

I do have shore power available, so more margin for energy loss.


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## zibadun (Mar 19, 2010)

prroots said:


> I received mine today based upon that item number. Turns out the chips are by Prolific. I wonder how one gets the ftdi chips?
> Pete


hmm a bummer. sorry for giving a bad lead. they must have switched the vendor. but it sounds like you've figured out the problem

i'm not anywhere close to crossing the gulf stream but I find that AIS receiver and 441 are useful even in local waters. I was coming out of a channel today and got a nice early warning about a vessel plowing through the West river here at the Chesapeake. Easy enough to change course a bit to avoid close approach.

I've also tested AIS by sailing near anchored tankers and the alarm worked just fine as I was getting close.

I think the default setting was for about a 2 minute warning before collision - not sure this is enough to get out of the way of a big ship going at 25 knots. May have to play around and find something that works OK in a busy bay without giving too many false alarms.


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## NICHOLSON58 (Feb 22, 2009)

Vesper Marine: AIS WatchMate - Dedicated Marine Collision Warning System Here is the link to Vesper Marine Watchmate 850. watch their videos. It may be worth it to spend a bit more for a dedicated device that only uses 3 watts instead of having to operate a series of interconnected power users. It has its own GPS and you can buy their antenna splitter if you want to share your VHS antenna. It has Stealth mode (receive only) and filtering to remove all non-danger targets and can run anchor watch as well. You can set the alarm perimiter out to whatever didtance suits your current need. Its output is also available for use on your chart plotter if you need it.


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## zibadun (Mar 19, 2010)

NICHOLSON58 said:


> Vesper Marine: AIS WatchMate - Dedicated Marine Collision Warning System Here is the link to Vesper Marine Watchmate 850. watch their videos. It may be worth it to spend a bit more for a dedicated device that only uses 3 watts instead of having to operate a series of interconnected power users.


where were you last winter?  . well I tend to keep the chart plotter and radio on anyway so might as well have AIS targets show up. The added bonus is that I can easily call any of the AIS ships using DSC. I'm too lazy to lookup but I'll bet power penalty for having AIS option isn't that much. Another benefit is that I can send DSC distress as well as pick up emergency calls and have them show up on gps (not really related to AIS). Can't really do any of that with the watchmate. The reason it's using low power is that it's really not doing much. (figuring out the CPA and setting off an alarm is not a complex computation) These days it's quite common to have low power GPS modules (e.g. SIRF star III) and vhf receivers and microcontrollers is - does not warrant a high price tag, IMHO


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## prroots (Nov 13, 2010)

zibadun said:


> where were you last winter?  . well I tend to keep the chart plotter and radio on anyway so might as well have AIS targets show up. The added bonus is that I can easily call any of the AIS ships using DSC. I'm too lazy to lookup but I'll bet power penalty for having AIS option isn't that much. Another benefit is that I can send DSC distress as well as pick up emergency calls and have them show up on gps (not really related to AIS). Can't really do any of that with the watchmate. The reason it's using low power is that it's really not doing much. (figuring out the CPA and setting off an alarm is not a complex computation) These days it's quite common to have low power GPS modules (e.g. SIRF star III) and vhf receivers and microcontrollers is - does not warrant a high price tag, IMHO


Thanks. Your points are well made. We would expect to have our gx2150 and 441s chartplotter on at all times while underway so the energy penalty is not so real. We just made a non-stop 1000 nm passage from Fajardo, PR to Ft Pierce, FL and I will say that having a transponder would have been useful to alert ships of our presence.

Our OpenCPN software generated the alarm. We then (for the first time) used the DSC capability of gx2150 to call the MMSI of ship to negotiate safe passing. The beauty of this is that an alarm is generated on bridge of the ship and the system automatically switches to the channel you designate once acknowledged thus avoiding ch 16. In years past, we call and call with no response. Now they get an alarm in their face which, apparently, is much harder to ignore With an eye to the budget, we are very happy with the gx2150; it's an amazing piece of equipment.
Pete


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## zibadun (Mar 19, 2010)

I'm curious what is a typical exchange when meeting ships at sea. Do you contact only the ones that are flagged as danger targets or is it typical to call any ship within sight? 

I've read the class B transponders often don't show up on tankers' displays. I guess nav systems used by the big commercial vessels are not required to be compatible with class B, and it's not as reliable as class A anyway (only 2W of output power)


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## SVAuspicious (Oct 31, 2006)

zibadun said:


> I'm curious what is a typical exchange when meeting ships at sea. Do you contact only the ones that are flagged as danger targets or is it typical to call any ship within sight?
> 
> I've read the class B transponders often don't show up on tankers' displays. I guess nav systems used by the big commercial vessels are not required to be compatible with class B, and it's not as reliable as class A anyway (only 2W of output power)


Offshore I call the ships that make me nervous. I don't count on the electronics to tell me what to be nervous about, but CPA and TCPA from the chartplotter/AIS or the radar do educate my thoughts. *grin*

Your sources of information about the display of Class B information are incorrect. Some of the older Class A displays did not show the static information from Class B transponders correctly but the dynamic information does show up. Software updates have pretty well solved that problem.


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## zibadun (Mar 19, 2010)

SVAuspicious said:


> Your sources of information about the display of Class B information are incorrect. Some of the older Class A displays did not show the static information from Class B transponders correctly but the dynamic information does show up. Software updates have pretty well solved that problem.


 I was reading here (the Pink lady collision report) : http://www.atsb.gov.au/media/1539485/mo-2009-008.pdf

around page 23 they talk about possible issues with class B AIS

although it does seem like a user error more than equipment issue


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## SVAuspicious (Oct 31, 2006)

zibadun said:


> I was reading here (the Pink lady collision report) : http://www.atsb.gov.au/media/1539485/mo-2009-008.pdf
> 
> around page 23 they talk about possible issues with class B AIS
> 
> although it does seem like a user error more than equipment issue


Agreed. The report in total is interesting and the section on AIS is illuminating. In particular they note:



> The report noted that the lack of detection was more likely to occur if the ship's Class A AIS unit only displayed the Class B vessel's MMSI number because the Class A unit was not capable of decoding and displaying the name of the vessel. The report also noted that the lack of detection issue was, to some extent, caused by vessel masters not recognising the detection on their AIS unit display.


This is consistent with my statement that older Class A AIS displays don't properly decode the static information from Class B transponders. Things move fast in technology and software updates are fixing the problem. In the year I have had a Class B AIS transponder aboard Auspicious I have contacted a number of commercial ships (it's lovely to be able to call them by name). Heck in the middle of the night any voice is entertainment. *grin* Only one ship of many dozens didn't know I was out there and they could "see" me on AIS when they looked. As may be inferred from the Ella's Pink Lady report, they didn't see vessel name in their target list but I was displayed on the chart display with position, course, and speed.

This will only get better with time.


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## prroots (Nov 13, 2010)

zibadun said:


> I'm curious what is a typical exchange when meeting ships at sea. Do you contact only the ones that are flagged as danger targets or is it typical to call any ship within sight?


We usually set AIS to alarm if TCPA is < 30 minutes and CPA is < 2 miles. Once the alarm occurs we monitor. When the vessel is approaching a distance of approx. 8 miles we select their MMSI on DSC and issue an automated alert on ch 69. Once the call is acknowledged we call via voice and negotiate a safe passing. This mostly serves to make them aware of our existence. We don't like to do this much before 8 miles since they might not yet be able to see us visually or on radar. Typically, this wakes them up and after a moment or two they find us on radar. Of course, we tell them where we are in relationship to them eg, 8 miles SouthEast of your location.
Pete


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## zibadun (Mar 19, 2010)

prroots said:


> We usually set AIS to alarm if TCPA is < 30 minutes and CPA is < 2 miles. Once the alarm occurs we monitor. When the vessel is approaching a distance of approx. 8 miles we select their MMSI on DSC and issue an automated alert on ch 69. Once the call is acknowledged we call via voice and negotiate a safe passing.
> Pete


I don't know if Standard Horizon has a sense of humor or what, but their ch. 69 is marked as "Pleasure". Not sure if 13 is any better or it's only for harbors (the tugs/large vessels limited by draft are required to monitor it here)

Received a first DSC distress today (N. Chesapeake). I thought the radio was going to jump out of its mounting bracket. The call was strange though - no position/nature of distress or any other info.


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## prroots (Nov 13, 2010)

zibadun said:


> I don't know if Standard Horizon has a sense of humor or what, but their ch. 69 is marked as "Pleasure". Not sure if 13 is any better or it's only for harbors (the tugs/large vessels limited by draft are required to monitor it here)


Thanks. Interesting about the channel numbers! When making the DSC alerts not all channels are listed as options. Here is a link for the intended use of channels: FCC: Wireless Services: Ship Radio Stations: Data: Channels. Channels 13 and 67 are for ships so don't know if pleasure crafts are allowed to use them even though the application seems appropriate. It would be interesting to find out what the recommended channel is for pleasure crafts to communicate with ships for navigational purposes.
Pete


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## Camiri (Aug 29, 2011)

*Raymarine AIS*

Have used AIS500 and M-Tech MT500 AIS for a while, if you have a Raymarine SeaTalk setup check my experience http://bavariacruiser.blog.com


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## xymotic (Mar 4, 2005)

Best for the buck I have to vote for the West Marine Class B transponder.

receive AND transmit for $500, and they do a lot of nice work to pre-configure baud rates and such for your specific application to make it as plug and play as possible.


*note: I do work @ WM though


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## donradclife (May 19, 2007)

We turn the chartplotter off when we are offshore-no need for it and its power draw--and use the Watchmate with its low power draw and excellent alarm logic. We have a West Marine transponder with the Watchmate display, but would probably go with the new Watchmate transponder/display if we were starting over. 

I talked to a couple of ships while we were coming back from Hawaii--more to pass the time of day than for any collision-avoidance issues. One them said that he was running two Furuno AIS units--the newer one picked up my static data, and the other one just showed me as a target with my MMSI number.

Offshore, we set the alarm for a 1 mile CPA and a TCPA of less than 45 minutes. I have a switchable external alarm connected to the Watchmate--Radio Shack's loudest 12v siren, about 5 times as loud as the engine--and there is no way anyone on board is going to sleep through that.

If the alarm goes off, I change course to clear the ship by over 1 mile, (preferably port-to-port if anywhere near head-on). The Watchmate has a CPA display which shows the relative position of the vessels at the time of CPA, which makes it very easy to determine which way to turn. I usually detect the ship's Class A signal before they detect me, allowing me to set up a safe situation before they even know I'm there. I make a note of the ship's original course, letting me know if they make a turn once they know I'm there. 

Usually the ship's keep their heading, or turn to increase the CPA, but I had one turn into me--he was near head-on,passing him green-to-green with a CPA of 1.5 miles, and he made a starboard turn. I called him on the VHF, and he confirmed he wanted to go red-to-red, so I had to go starboard 20 degrees to get a 1.5 mile CPA on the 'correct' side.

All-in-all, the AIS is a great tool. As we approached San Francisco, I was chatting with a NZ cruiser who didn't have AIS, and who said that he spent a stressful night dodging ships--and that was before we hit the fog. I slept well, even with two inexperienced watchstanders, knowing that the Watchmate would wake me if necessary and give me the necessary collision avoidance information at a glance.

Once inshore,where ships turn to follow channels and traffic lanes, I tend to use the OpenCPN AIS display, as it lets me anticipate the ship course changes.

Disclousre--I have no connections to Vesper or West Marine.


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