Raytheon RL70C + Chartplotter

[ipdj]

I bought a RL70C for the radar, but would now like to hook up the chartplotter functions too. Can anyone help me out with what sort of GPS antenna and extras I need to get? Presumably a differential GPS antenna is ok, but what sort of cables, junction boxes do I need to hook it up? Seatalk 3 pin socket at back of monitor sitting empty.

[noelex 77]

Any GPS with NMEA 0183 or sea tak output will be OK (that is 95% of GPS units)
I use a Furuno GP-32 it has a standalone display with low power consumption and an anchor alarm, when you dont need the chartplotter on.

[ipdj]

Thanks. So how do I hook up a non raytheon antenna? Can I plug it into the Seatalk socket, or do I need some sort of a junction box etc?

[noelex 77]

Originally Posted by ipdj

Thanks. So how do I hook up a non raytheon antenna? Can I plug it into the Seatalk socket, or do I need some sort of a junction box etc?

A non Raytheon GPS will connect via NMEA not seatalk. (seatalk is only used by Raymarine). The power lead for the 12v connection on the RL units has got extra wires for NMEA input.
Connect the GPS NMEA output wires with the RL NMEA input wires. You can use a junction box or just join the wires (solder and heat shrink is the most reliable). No conversion box is needed.
The manufactures don’t make it easy with different colour codes and confusing handbooks, but if you can tell us the GPS unit you wish to buy someone will tell you the correct wires hook up.
You can buy a Raymarine GPS instead, like the 125 unit which will connect via seatalk, but there are better and cheaper units available from other manufactures that will connect with only a little extra work.

[ipdj]

Thanks. I really appreciate your help. I will go and have a look at the power lead and start looking for an antenna. Really appreciate this.

[noelex 77]

Originally Posted by ipdj

Thanks. I really appreciate your help. I will go and have a look at the power lead and start looking for an antenna. Really appreciate this.

The power lead for the RL chart plotter should have a thin:
Orange wire This is NMEA + input
Yellow wire This is NMEA - input

Connect theses to the NMEA output wires (both + and - wires need to be connected, + to + and – to -) from most GPS units and the RL unit will know the position.

The correct NMEA output wires from the GPS unit to connect to the orange and yellow wires will be in the handbook for the GPS unit. Unfortunately there is no standard colour coding so the correct wires vary from one GPS unit to another
.

[SoonerSailor]

We hooked up the Garmin GPS17x to our RL70CRC with good results. Good quality for a good price.

[vientoman]

I have a raytheon pathfinder RL70, a scanner and a gps antenna. I picked these up at a marine swap meet for next to nothing and my expectations were mainly just to have the stuff in front of me that I could use to learn a little bit about marine radar. I was able to connect the raytheon scanner unit to the RL70 and did get a nice radar signal on the LCD. However, I would really like to see if I could also get the GPS function to work.

I understand some GPS units have internal batteries that eventually weaken and fail so I opened the GPS antenna unit up and with a little creativity, I was able to replace the 3v button battery. I did this mainly to give this GPS unit a fighting chance.

The GPS antenna has five wires:

red
yellow
green
brown
bare wire

The seatalk cable that I have has three wires:

red
green
yellow

I tried the obvious and connected the three matching wires; plugged it all in to no avail.

Again, since I'm not currently in a foggy ship channel, there is no real concern but It would be nice to see If I could get the GPS to function.



Any suggestions about how to investigate GPS functionality?

[noelex 77]

You do not say which GPS model it is, but this should do it. Ignore the differential wires if its not a differential unit.

[Dockhead]

Originally Posted by noelex 77

? . . (solder and heat shrink is the most reliable). .

For the sake of good order, a good crimp is generally specified over solder, since vibration will break up soldered joints, plus solder-saturated wire strands become brittle and break.

In practice, few sailors have knowledge or equipment to do a really good crimp, so in real life, it might not make much difference. But for whatever it may be worth, you won't see many pros using solder for wire joints.