Using a Plotter as a cockpit repeater

[affinite]

Background
I use OpenCpn on a laptop at the navstation. GPS input comes from an old Raytheon GPS and I have a Raytheon cockpit repeater which displays basic info wrt distance to waypoint XTE, SOG etc. This is a system Ive happily used for a number of years on my previous boat but on this one the repeater is small and difficult to read so I'd like to replace it. I was thinking of the Nasa GPS repeater but I have recently inherited a Navman Tracker 5380 chartplotter which IMO is really to small to be used as a chart display or route planning device so I wondered if it could be used in place of the existing cockpit repeater.

The 5380 manual does say that it can be configured for external NMEA GPS input so I assume I could link it to opencpn, configure it for rolling road or data window display and it would then be my repeater. An added bonus would be that if I retained the external GPS aerial it would also be a backup for the PC based system should that fail.

Question
Has anyone tried to configure a small plotter in this way ?
If configured to receive GPS data from an external NMEA source do you think that the 5380 would also display XTE type sentences which have been externaly generated or will it simply use the external NMEA input for basic position info and assume it is going to generate the XTE type data (it is a chart plotter after all)

 

[Paul3745]

how do you reply to this site just joined,,,,,bit complecated

 

[Seajet]

I generally find a repeater costs very near the same as a complete separate system, I prefer having that 'redundancy' rather than eggs in one basket.

 

[affinite]

SJ - thats the point ... The Navman is a chart plotter in its own right so it does provide the redundancy. Should my laptop fail, I simply set the navman to look to its own GPS antena and it will run standalone.
The reason for using it as a repeater is so that routes created on the navstation PC can be followed on the repeater (plotter) up top.

Paul - think you have found how to reply to a post
(Welcome to the forum bye the way)

 

[grumpy_o_g]

Question
Has anyone tried to configure a small plotter in this way ?
If configured to receive GPS data from an external NMEA source do you think that the 5380 would also display XTE type sentences which have been externaly generated or will it simply use the external NMEA input for basic position info and assume it is going to generate the XTE type data (it is a chart plotter after all)

I'd say no I'm afraid. A quick look at the manual shows the NMEA sentences that are permitted (i.e. the one's the manufacturer will let you use, regardless of whether or not the system is capable of using them) as:

NMEA

• NMEA 0183 ver 2 4800 baud

• Inputs from compatible instruments: DBT,
DPT (preferred), GGA, GLL, GSA, GSV, MTW,
MWV, RMC, VHW, VTG

• Outputs, for compatible instruments: APA,
APB, BWR, GGA, GLL, GSA, GSV, RMB, RMC,
VTG, XTE

The sentences you need are the ones starting with W, especially WPL (way point location). There's a pdf file of them here http://www.tronico.fi/OH6NT/docs/NMEA0183.pdf. It might not be the latest revision of NMEA 0183 but I don't think the bit you're worried about has changed.

I would guess that NavMan use proprietary sentences over NMEA to transmit Waypoint data. Unless your software on the laptop can create those proprietary sentences then I think you're stuck with the inputs listed above. I'd be delighted to be told I'm wrong by someone with more knowledge though.

 

[neilf39]

Unless the plotter can be configured from its menus to act as a repeater I would say it would still act as an independent plotter. The external GPS would be just an alternative to the internal receiver and it would expect the standard receiver inputs, not the derived data from another plotter. What your openCPN plotter would be sending if it expected to be talking to a repeater would probably make no sense to the plotter you want to use as the repeater and so possibly not work at all if configured to use the external receiver unless it does receive the standard expected external receiver sentences.

 

[affinite]

Thanks guys - I thought that might be the case. I'll try and hook it up and see - just in case I get lucky