Chartplotter to radio connection

Yorkshire Exile

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Hello everyone need some help please. My new (old) boat has a Lowrance HDS 5M plotter and a Lowrance Link 5 radio. Both work fine but the problem is connecting them so the radio has a GPS provided position. The connection I have inherited is several gaily covered flimsy wires from the chart plotter going to a plastic four section connection block with similar coloured wires leading to the radio. Because these wires are clearly not suited to this type of connection block they have broken free and it’s impossible to know which chart plotter wire connected to which radio wire (and I don’t know if it ever worked). I have managed to work out from the appalling manuals that the radio requires 4800 Baud NMEA 0183 & the type of data sentences required (if you’ve now decided this post isn’t for you, I don’t blame you!). I have surprised myself by managing to negotiate the menus on the chart plotter to provide the correct output for the radio. So my question is what wire connects to what wire? This is what the manuals say:

Radio

Red – not used
Orange – NMEA out (+) to GPS
White – not used
Green - NMEA in (-) from GPS
Yellow – NMEA in (+) from GPS
Black - NMEA out (-) ground
Blue – not used
Grey – not used

Chart plotter

Green RX (-) Transmit (-)
Orange RX (+) Transmit (+)
Shield (Ground) Ground
Yellow TX (+) Receive (+)
Blue TX (-) Receive (-)

HELP...............................................................
 
Hello everyone need some help please. My new (old) boat has a Lowrance HDS 5M plotter and a Lowrance Link 5 radio. Both work fine but the problem is connecting them so the radio has a GPS provided position. The connection I have inherited is several gaily covered flimsy wires from the chart plotter going to a plastic four section connection block with similar coloured wires leading to the radio. Because these wires are clearly not suited to this type of connection block they have broken free and it’s impossible to know which chart plotter wire connected to which radio wire (and I don’t know if it ever worked). I have managed to work out from the appalling manuals that the radio requires 4800 Baud NMEA 0183 & the type of data sentences required (if you’ve now decided this post isn’t for you, I don’t blame you!). I have surprised myself by managing to negotiate the menus on the chart plotter to provide the correct output for the radio. So my question is what wire connects to what wire? This is what the manuals say:

Radio

Red – not used
Orange – NMEA out (+) to GPS
White – not used
Green - NMEA in (-) from GPS
Yellow – NMEA in (+) from GPS
Black - NMEA out (-) ground
Blue – not used
Grey – not used

Chart plotter

Green RX (-) Transmit (-)
Orange RX (+) Transmit (+)
Shield (Ground) Ground
Yellow TX (+) Receive (+)
Blue TX (-) Receive (-)

HELP...............................................................

To get the GPS position into the radio connect Chartplotter Orange & Green to VHF Yellow & Green resp. Note the VHF doesn't have a separate NMEA ground like the Chartplotter. Quite common but I'm surprised the same vendor has taken different approaches.

Check the manual about the VHF out. Probably 4.8Kb and probably DSC & DSE sentences, but that's just a guess.

PS Choc block connectors aren't really suitable for this. My personal preference is ring terminal blocks.
 
Last edited:
Chart plotter transmit - and + got to VHF NMEA in - and +

Chart plotter receive - and + go to VHF NMEA out - and +

Chart plotter VHF

Green >> Green
Orange >> Yellow
Yellow >> Orange
Blue >> Black

To connect, treat yourself to some Wago connectors from Screwfix.
 
Thanks IPDSN and PaulRainbow, very useful. I had a look at ring terminal blocks and Wago connectors online but I will need to see them in the flesh to understand how they handle these tiny wires. When I have connected similar wires on telephone extension boxes I think they used a type of grip which pierced the insulated cover of the wires without having to remove that cover to expose the wire itself. Is that what these connectors do?
 
Thanks IPDSN and PaulRainbow, very useful. I had a look at ring terminal blocks and Wago connectors online but I will need to see them in the flesh to understand how they handle these tiny wires. When I have connected similar wires on telephone extension boxes I think they used a type of grip which pierced the insulated cover of the wires without having to remove that cover to expose the wire itself. Is that what these connectors do?

With the ring terminal blocks I just crimp a small 4mm ring terminal on the end of each wire.

I think the Waco connectors are the type where you put the exposed end of the conductor in but they clamp the wire rather than it being screwed down like a choc block connector.
 
Thanks again, after a bit more research I am going to try jelly crimps. I will report back after trying them.

Interestingly after checking my previuos attempt before posing this question, I had followed the same wiring as suggested by IPDSN abd Paul Rainbow. The connection (or lack of it) may have been the problem.
 
We relied on the description of the wires you posted. Always worth double checking the manual and whatever is written on the boxes themselves if it doesn't work. Maybe a bit OTT for some but I actually draw up circuit diagrams myself before doing the connections and when everything works I have something to refer to three years later.
 
We relied on the description of the wires you posted. Always worth double checking the manual and whatever is written on the boxes themselves if it doesn't work. Maybe a bit OTT for some but I actually draw up circuit diagrams myself before doing the connections and when everything works I have something to refer to three years later.

Not OTT at all, just sensible!
 
I finally managed to do this. I think my OP with the manual extracts was wrong hence the solutions offered by Paul Rainbow amd IPDSN did not work. The key to understanding the manuals, for me, was when I realised TX means transmit and RX means receive. I'm sure the rest of the world knows this but I didn't. The other part of the solution was to use BT type jelly crimps - this ensured good connection without damging the wires.
 
Hope it works for you. I would solder the wires myself and cover them with shrink wrap. This gives the necessary strength to the junction and keeps water away from the connection. I have been known to do each wire and then use a larger diameter wrap on the bundles. Best done at home.
 
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