GPS antenna to feed into AIS reciever

SAWDOC

SAWDOC

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hi folks
looking for some advice please.
I would like to install a low cost AIS reciever on my Wauquiez Gladiateur. , I was thinking of the Nasa Clipper AIS reciever. It requires a GPS input and I thought i would purchase a GPS antenna whch I could fix on the pushpit rail. I dont have another suitable GPS source on board.

Could anyone suggest a suitable antenna type? I would also like the GPS antenna to provide GPS input for my Standard Horizon DSC vhf radio so i would need some splitter device also.

Thank you.
 
Several ways of doing it but the critical factor is a device that outputs NMEA GPS data. Passive antennas with a BNC type connector won't do that.

You'll be able to feed both AIS and VHF by simply connecting two wires to the output as long as the negatives are grounded together. No extra device needed.

You could use a cheap handheld GPS with a data cable. Has the advantage that you then have some basic GPS functionality.

Or use a dedicated GPS receiver such as Evermore SA-320.

Some may advocate using 5V based receivers with attendant signal and voltage transformers but for most it's a bit fiddly and perhaps unreliable if not robustly put together.

Either option would probably work well below deck, so try there first before rail.
 
Only just, seems Evermore have stopped making them. There are others of similar type but I've not looked st them to see what quality is like.

Re handheld GPS, the data cable usually has 12V power connection as well, so not reliant on batteries.
 
SAWDOC said:
hi folks
looking for some advice please.
I would like to install a low cost AIS reciever on my Wauquiez Gladiateur. , I was thinking of the Nasa Clipper AIS reciever. It requires a GPS input and I thought i would purchase a GPS antenna whch I could fix on the pushpit rail. I dont have another suitable GPS source on board.

Could anyone suggest a suitable antenna type? I would also like the GPS antenna to provide GPS input for my Standard Horizon DSC vhf radio so i would need some splitter device also.

Thank you.
Click to expand...

I'm not clear why an AIS receiver needs a GPS input, unless it does something else other than just receive AIS signals. :confused:

Ah, I see that it acts like a plotter so needs a GPS signal for that, although not a dedicated GPS like a transceiver so it could use an existing GPS/NMEA signal if there was one. :)

Richard
 
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SAWDOC said:
I would like to install a low cost AIS reciever on my Wauquiez Gladiateur. , I was thinking of the Nasa Clipper AIS reciever. It requires a GPS input and I thought i would purchase a GPS antenna whch I could fix on the pushpit rail. I dont have another suitable GPS source on board.

Could anyone suggest a suitable antenna type? I would also like the GPS antenna to provide GPS input for my Standard Horizon DSC vhf radio so i would need some splitter device also.
Click to expand...

There isn't a Nasa Clipper AIS - do you mean the AIS Engine 3 or the AIS Sart Plotter?

The standalone Evermore SA320 GPS receiver is often recommended and seems still to be available from JG Tech - http://jgtech.com/marine-gps.html#Evermore

You don't need a splitter device, the GPS receiver can simply be wired to several "listeners".
 
SAWDOC said:
hi folks
looking for some advice please.
I would like to install a low cost AIS reciever on my Wauquiez Gladiateur. , I was thinking of the Nasa Clipper AIS reciever. It requires a GPS input and I thought i would purchase a GPS antenna whch I could fix on the pushpit rail. I dont have another suitable GPS source on board.

Could anyone suggest a suitable antenna type? I would also like the GPS antenna to provide GPS input for my Standard Horizon DSC vhf radio so i would need some splitter device also.

Thank you.
Click to expand...

What GPS do you have? Might be a way to split out the NMEA from what you have, or another option might be to upgrade the radio to a SH GX2200 which has both GPS and AIS receivers.
 
GHA said:
What GPS do you have? Might be a way to split out the NMEA from what you have, or another option might be to upgrade the radio to a SH GX2200 which has both GPS and AIS receivers.
Click to expand...

In post #1 the OP states
I dont have another suitable GPS source on board.
Click to expand...

A radio upgrade would certainly be worth looking into, only costs about £70 more than the Nasa thing and doesn't need the external GPS, much better quality and an easy install.
 
RichardS said:
I'm not clear why an AIS receiver needs a GPS input, unless it does something else other than just receive AIS signals. :confused:

Ah, I see that it acts like a plotter so needs a GPS signal for that, although not a dedicated GPS like a transceiver so it could use an existing GPS/NMEA signal if there was one. :)

Yes the GPS input provides the boat position, allowing the AIS device to centre its display on one's own boat.

Richard
Click to expand...
 
PaulRainbow said:
In post #1 the OP states

A radio upgrade would certainly be worth looking into, only costs about £70 more than the Nasa thing and doesn't need the external GPS, much better quality and an easy install.
Click to expand...

Some sailing pals have made similar suggestions. I contacted one club member who purchased the Standard Horizon DSC GPS AIS VHF, asking him how he found it. He told me he had sent it back to SH - he noticed the device was intermittent in picking up AIS data, so not 100% satisfied. I am interested to hear if that is a common experience or a one off .
Another pal bought the SH DSC GPS VHF and ended up sending that back as well - i dont recall what his issue was but I am a little wary of putting all my expenditure in the SH basket.
 
Amazon sell the Evermore SA-320 albeit with the cable terminating in a USB plug - I’m probably seriously wrong but I can’t think of a reason why you couldn’t just snip off the USB plug and join thr wires to an appropriate NMEA plug?
 
SAWDOC said:
Yes the GPS input provides the boat position, allowing the AIS device to centre its display on one's own boat.
Click to expand...

Although that's interesting in itself. I have an AIS transceiver which I can use with a radar type display or a chart type display but if I had a receiver only then with either type of display where exactly would my own boat appear? I have always assumed that even a receiver would show one's own boat in the middle of the display as it could deduce that from the signals received from other boats .... but it sounds like I'm mistaken.

Richard
 
Wandering Star said:
Amazon sell the Evermore SA-320 albeit with the cable terminating in a USB plug - I’m probably seriously wrong but I can’t think of a reason why you couldn’t just snip off the USB plug and join thr wires to an appropriate NMEA plug?
Click to expand...
Don't do that! You are seriously wrong - it wont work.
 
For a little bit more than the combined cost of GPS and the NASA unit, you could get a Matsutec hp-33a ais transponder .

This has GPS, the display, and will output NMEA 0183 to the VHF.
 
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I agree with dolabriform, the Matsutec is a great bit of kit that will give you everything in one box. I am sat in front of mine right now and it is happily letting me know who is going in and out of the harbour.
If you go this route, make sure you buy the hp-33a and not the hp-33, as that is just the GPS unit without the AIS.
 
SAWDOC said:
Some sailing pals have made similar suggestions. I contacted one club member who purchased the Standard Horizon DSC GPS AIS VHF, asking him how he found it. He told me he had sent it back to SH - he noticed the device was intermittent in picking up AIS data, so not 100% satisfied. I am interested to hear if that is a common experience or a one off .
Another pal bought the SH DSC GPS VHF and ended up sending that back as well - i dont recall what his issue was but I am a little wary of putting all my expenditure in the SH basket.
Click to expand...

If you ever see a post on here for VHF recommendations SH always come out top. The experience of your friend above is definitely not common.
 
RichardS said:
Although that's interesting in itself. I have an AIS transceiver which I can use with a radar type display or a chart type display but if I had a receiver only then with either type of display where exactly would my own boat appear? I have always assumed that even a receiver would show one's own boat in the middle of the display as it could deduce that from the signals received from other boats .... but it sounds like I'm mistaken.

Richard
Click to expand...

A receiver does indeed need a GPS position to centre the display. Also to work out CPA and so forth.
I suppose in theory, you could work out the receiver's position from the delays of the received signals, but it's not trivial and what happens out at sea where there's only one target in range?
A gps receiver is the way to do it, a ublox module in a box, $10 oem cost?

ISTR many years ago firing up a NASA 'AIS radar' with a manually input position for testing. I used a position in the Solent, not our true position which was somewhat inland and lacking in collision potential.
 
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