Cheapest way to add GPS to ST60 speed to get SOG

[DHV90]

Hello!

Having finally repaired my ST60 transducer with a broken thermistor, Im interested in adding GPS to the system to get SOG and then have a repeater at the chart table with speed, depth and course etc.

Is there an easy way to integrate a GPS aerial to a small Seatalk system, or does it have to get decoded by a plotter or something expensive before it can get read by the ST60 instruments?

Thanks!

 

[sailorman]

SOG = HH GPS is the easy way

 

[DHV90]

Completely agree! Already have a handheld, but what Im really looking for is a way of getting GPS on the integrated ST60 systems rather than alternatives. Then I can weigh up the options and see if it's worth adding to the ST60 system or not.

 

[RichardS]

Hello!

Having finally repaired my ST60 transducer with a broken thermistor, Im interested in adding GPS to the system to get SOG and then have a repeater at the chart table with speed, depth and course etc.

Is there an easy way to integrate a GPS aerial to a small Seatalk system, or does it have to get decoded by a plotter or something expensive before it can get read by the ST60 instruments?

Thanks!

Assuming your ST60 has the 3-pin Seatalk socket at the top then I don't see why you shouldn't purchase an GPS antenna that outputs Seatalk like my Raystar 125 (old stuff now) and connect that directly to the Seatalk pins without a chartplotter. However, I don't know whether you can choose whether the ST60 displays the paddlewheel speed or the GPS speed and whether you can select which to display or whether you have to disconnect the paddlewheel to show GPS.

The manual for your instrument might well give the necessary information.

Richard

 

[sailorman]

Assuming your ST60 has the 3-pin Seatalk socket at the top then I don't see why you shouldn't purchase an GPS antenna that outputs Seatalk like my Raystar 125 (old stuff now) and connect that directly to the Seatalk pins without a chartplotter. However, I don't know whether you can choose whether the ST60 displays the paddlewheel speed or the GPS speed and whether you can select which to display or whether you have to disconnect the paddlewheel to show GPS.

The manual for your instrument might well give the necessary information.

Richard

try investigating nema or a usb gps

 

[DHV90]

Hi Richard, Ive tried the manual and its not very clear on this!
It is the standard 3 pin seatalk, and the display has options to show SOG or STW along with a number of other functions,

I was looking at Raystar 125s and similar on ebay but they seem to have an extra black and brown wire as well as the red green and yellow seatalk so was thinking that the data might need managing somehow

 

[rogerthebodger]

Hello!

Having finally repaired my ST60 transducer with a broken thermistor, Im interested in adding GPS to the system to get SOG and then have a repeater at the chart table with speed, depth and course etc.

Is there an easy way to integrate a GPS aerial to a small Seatalk system, or does it have to get decoded by a plotter or something expensive before it can get read by the ST60 instruments?

Thanks!

I am looking at doing something similar by taking the SOG from a GPS mouse and converting to STW nmea by using a PIC to change the nmea message header so my SIMRAD speed display will recognise the massage. You would need something similar to convert the input nmea to the seatalk message format.

 

[RichardS]

Hi Richard, Ive tried the manual and its not very clear on this!
It is the standard 3 pin seatalk, and the display has options to show SOG or STW along with a number of other functions,

I was looking at Raystar 125s and similar on ebay but they seem to have an extra black and brown wire as well as the red green and yellow seatalk so was thinking that the data might need managing somehow

The extra wires on the 125 are for when it's used in NMEA0183 mode. Mine used to be connected to the back of my chartplotter in Seatalk mode using just the Seatalk wires. The 3 pins then had wires connected to the same 3 pins going to the ST60+ Tridisplay so I can't see that the chartplotter was actually doing anything with the RS125 signal.

I now have my 125 connected in NMEA mode to a different instrument and this uses the different wires. The RS125 manual is very clear about which wires need to be used and/or grounded to produce the two different outputs. I'm sure the manual is available online but tell me if not and I'll attach it.

Richard

Just checked my notes from last year : RS125 in Seatalk mode requires Green and Red connected together for power input, Ground and Brown connected together for ground and yellow is the signal. NMEA requires Ground, Brown and Green to be connected together for NMEA -ve, Yellow is NMEA +ve and Red is power.

 

[duncan99210]

There's a link here http://c470.jerodisys.com/470Lib/gps_125.pdf to the Raystar 125 manual, showing how to connect it to Seatalk. Page 4 is the one showing the connections.

 

[bitbaltic]

Hello!

Having finally repaired my ST60 transducer with a broken thermistor, Im interested in adding GPS to the system to get SOG and then have a repeater at the chart table with speed, depth and course etc.

If you don't already have that repeater, then the best solution I can think of would be to source a cheap/older chartplotter (perhaps a s/h model with an external antenna), position it at the chart table, and connect it to your Seatalk instruments. You will then get GPS data to the Seatalk network and Seatalk data on a "repeater". If all you want is some numbers it doesn't matter if it has old/any charts. Most older NMEA0183 plotters would fit the bill for a smallish budget.

 

[prv]

Most older NMEA0183 plotters would fit the bill for a smallish budget.

It all sounded pretty reasonable until this point

If the main purpose is to get GPS data onto the Seatalk bus then he's going to need specifically an older Raymarine plotter with Seatalk, not any old NMEA0183 one.

Personally I'd suggest a Raymarine GPS mushroom if there's a secondhand one going cheap somewhere, otherwise a generic GPS puck and one of the various semi-hobbyist NMEA<->Seatalk converter boxes that exist.

Some of the latter even have small displays on them, which might meet his needs for a repeater.

Pete

 

[RichardS]

Hi Richard, Ive tried the manual and its not very clear on this!
It is the standard 3 pin seatalk, and the display has options to show SOG or STW along with a number of other functions,

The manual for my ST60+ says

The instrument shows the current speed and selected speed units. The speed information is
obtained either from a speed transducer, or derived from Speed Over Ground
(SOG). SOG is available if you are connected to a SeaTalk system to which a
compatible GPS is also connected. The source of speed information (transducer or SOG) is selected during Dealer
calibration.

I remember now that all you have to do is go into dealer calibration mode (a few more key presses than user calibration but not a problem) and select whether you want to display GPS or paddlewheel data to be displayed. I has to do this when I disconnected the Seatalk GPS feed and fed that in NMEA mode into a CruzPro SOG1 and then fed that back into the ST60 as paddlewheel simulated data. This ensured that the GPS speed data, which I still have available on the network from the AIS transceiver, is not displayed.

Although I can switch back to GPS data through Dealer calibration, it's not something you could do easily on the move by pushing a button. If you look at the ST60 manual you'll see what's required and it's probably half a dozen button presses, some at the same time which have to be well coordinated.

Richard

 

[bitbaltic]

It all sounded pretty reasonable until this point

If the main purpose is to get GPS data onto the Seatalk bus then he's going to need specifically an older Raymarine plotter with Seatalk, not any old NMEA0183 one.

Personally I'd suggest a Raymarine GPS mushroom if there's a secondhand one going cheap somewhere, otherwise a generic GPS puck and one of the various semi-hobbyist NMEA<->Seatalk converter boxes that exist.

Some of the latter even have small displays on them, which might meet his needs for a repeater.

Pete

Good point! Momentary lapse of memory. Quite true he can't just patch 0183 in. See, there's always a reason not to buy Raymarine

 

[prv]

If you look at the ST60 manual you'll see what's required and it's probably half a dozen button presses, some at the same time which have to be well coordinated.

This thread just gets more bizarre. Every ST60 system I've come across, including my own, cycles through the various different speed displays by pressing the left-hand "Speed" button. I have no idea what your calibration is all about, but if the OP wants to choose between displaying GPS speed and log speed, this is how he would do it.

Pete

 

[RichardS]

That's only selecting the different speed options which are available using the speed data being supplied to the instrument. Where there are two sources of data, paddlewheel and GPS, you have to tell the ST60+ which data source to use and that can only be done in the Dealer cailbration mode, presumably because the Dealer knows whether a paddlewheel is fitted to the boat or not.

ST60+ Tridata Dealer calibration section:

I'm not familiar with any other Raymarine displays.

Richard

 

[DHV90]

Just to clarify, I know how to reach SOG mode, that bits easy, press speed a few times to cycle through until it reaches SOG

What I needed to work out was whether GPS information had to be decoded between the GPS antannae and the Seatalk system. Both the paddle wheel and GPS can be used as speed inputs simultaneously, sort of the point of seatalk surely?!

The manual does say that SOG is possible with GPS on the system, but doesn't go into detail on how to join GPS on the seatalk system, hence my asking!


Does anyone have a link for some NMEA to Seatalk converters with a screen? Cant find any yet, but it looks like a simple GPS antennae will be the simplest solution.

 

[earlybird]

Does anyone have a link for some NMEA to Seatalk converters with a screen? Cant find any yet, but it looks like a simple GPS antennae will be the simplest solution.

The ST60 Graphic will convert some NMEA to Seatalk, inc. speed. Not particularly cheap though. Some ST Autopilot displays will also do this.

 

[Gypsy]

That's only selecting the different speed options which are available using the speed data being supplied to the instrument. Where there are two sources of data, paddlewheel and GPS, you have to tell the ST60+ which data source to use and that can only be done in the Dealer cailbration mode, presumably because the Dealer knows whether a paddlewheel is fitted to the boat or not.

ST60+ Tridata Dealer calibration section:

I'm not familiar with any other Raymarine displays.

Richard

I think the selection process you show is for the TriData only. For ST60 speed/log you can select from the front panel as PRV shows.

So the simplest method of showing Boat Speed (log wheel) and SOG is to add a Seatalk RS112, RS120 or RS125 GPS. No other hardware required. It will plug directly into one of the ST sockets at the back of an ST60 and get its power from the existing ST bus/power feed.

 

[RichardS]

I think the selection process you show is for the TriData only.

You could well be right, which is why I specifically said that I am referring to my ST60+ Tridata. If I ain't done it, I don't post it!

Richard