Can you connect 1 gps to both radio and sounder?

[stingau]

Any tech minded assistance gratefully accepted.

Just brought some new toys for my latest acquision. Can I connect my trusty old reliable Garmin Etrex Legend to
A/ Humminbird 717 sounder

B/ DSC VHF radio

Both are nmea compliant but was wondering if by splicing them both together them joining them to the GPS cable will it work. The other option is constant plugging and unplugging or buy 2 GPS.....

any advise welcome or if anyone has already set this up

[Kevaclone]

A couple of things to consider
do either of the devices send power to the GPS unit?(probably not as they can be connected to self powered units)

Are the TX/RX signals from each device different so as not to confuse the GPS so that it sends the correct data and can each device filter out data that is not intended for it, this would be the biggest hurdle

if you can find a serial splitter then plug it in and try
a proper splitter would be needed so that the two devices don't interfere with each other

Kev

[MEGA'bite]

give trymax marine a call they will know 32453633 brisbane

[coucho]

Just wondering what the point of hooking your gps to the radio is whast the benifit of it?

[SatNav]

1. Yes that will work

2. The Huminbird will require a GPS connection cable

[stingau]

Just wondering what the point of hooking your gps to the radio is whast the benifit of it?

Coucho, the benefit is in the DSC function this radio is capable of sending and recieving digital data and global positioning ie if I require emergency assistance I hit the distress call button and my gps linked accurate position is sent to all those monitoring save having to rush a calculation which could be in error also if I recieve a distress call from another party I can quickly offer assistance with the combination reciving the map co ords and a course is auto calculated.

I take my young son out with me and for piece of mind that if something goes wrong he knows to hit the button and rescue services not only know who I am but where I am.

[coucho]

thanks stingau I had idea that you could set that up

[Fatenhappy]

Just a couple of quick points re NMEA in general ....

Although being NMEA compliant there are still the two diferent protocals of NMEA 2000 and 0183. Some can be connected together some cannot, depends on the manufacturer. Worth just having a squiz to make sure yours are are the same or at least compatible.

The NMEA system itself is a balanced digital bus system that needs to be correctly terminated. If there is only one device (sensor) the end of lines balluns are of a different impedence to those where multiple (more than one) units are plugged into the system.

Really besides that everything else is easy, just add another tee connector, plug in the new sensor/device bring it up in the set up menu so the system recognises it and off you go.

Re the VHF DSC, nothing hard there either, just wire everything in as marked with the GPS and the rest is gold ....

Hope it all goes well !!!

Cheers
Greg

[SatNav]

1. NMEA0183 and NMEA2000 are not compatible regradless of manufacturer

2. NMEA2000 is not relevent to this query

[honda900]

SatNav,

I think fatnhappy meant that each of the protocols had devices that were not necessarily compliant and could not talk to each other.

Maybe a better explanation is that nmea devices need to support either one or bothe protocols to talk to each other, think of it more as a language for communication.

I.e nmea2000 requires 2 devices that talk the same protocol or language if you like.

Same with the NMEA0183 devices, both must suppor the same protocol.

Some devices are not 100% compliant and have some issues talking on the network, although it shoudl be ratified against the standard, they dont always support 100% of the features.

A lot of the newer devices support both protocols.

Regards
Honda.

[25_ponies]

Stingau, for all the hassles connecting up your Etrex - getting the right cables, having to power it, finding somewhere for it to sit where someone won't trip over it or the cables but still be able to access, I'd go for the Humminbird GPS module for the 717. This will integrate no worries with the sounder, and will also give you a 2 wire tail with NMEA out that you can connect up to your radio. This is a really simple install and (almost) guaranteed to work.

Cheers,

Alan.

[stingau]

Alan, you wouldnt by chance know the product/model number for this unit. I have searched on line and found a 16 channel unit in the states but it doesnt seem to be avail here in Aust., Ive only checked BLA's website will call them today.

Steve

[SatNav]

1. GPS receiver is GR4

[culbara]

Dont forget before DSC wuill work you have to apply to gov for a MMSI no and before they will issue on you have to show proof of a radio sicense which yo can do course at a lot of Coastguards the Nooloolaba one does the course there on a regular basis and they do it through Maratime University at Tasmania

[Bowser]

Stigau, from my understanding you won't be able to conect these units. I believe that they are all 0183 units and that under this protocol you can generally only conect 2 units. This is because the 0183 protocol is not a network in the way that the 2000 is. Connection is direct and units generally have an output and an input set of wires which conect to one unit only. Some units do have multiple core cables but the 2000 compliant units are totally connectable as the info tavels up and down the backbone and the various units pick the info they want to use or display. It is a pain for anyone without the 2000 compliant units when you see the explosion in possible connections coming for the 2000 network. Apart from the GPS connection there is a plethora of engine managment connections, fuel flow, tank level, temperature senders, etc etc etc that are around from a huge variety of manufacturers. There are some sensational units around, like the fuel filler cap that has a display built into it so that you can see the tank level as you fill the boat.

[SatNav]

"from my understanding you won't be able to conect these units. I believe that they are all 0183 units and that under this protocol you can generally only conect 2 units."

1. That understanding is misunderstood. NMEA0183 is very capable of supporting more than a single unit to unit connection.

2. There is no problem as per the original requirement.