NMEA0183 questions

[xo4001]

This is probably a question for Bob

Recently installed a old radar Koden MDC741 and its working good
Found that it can accept NMEA input also my VHF can accept this
My question is can I buy a GPS puck with this output and connect both on this puck or do I need some kind of a splitter
My chart plotter fish finder raymarine dragon fly has no NMEA output so the only solution I see is to buy a puck
Other question is can I short the cable between the Radar dome and display because it's far to long but dont know if this has any effect on the working of the unit
Any input is welcome
Thanks in advance

[SaltH2OHokie]

I bought a Garmin puck that fed 3 0183 devices with no splitter...

Can't help with radar cord.

[seabob4]

OK....some MFDs/Radars/VHFs will work with any GPS antenna...some won't.  Lowrance and Raymarine being the 2 most noted.  That being said, I would contact Koden, but it looks like it's gonna have to be an email, as their contact page only lists facilities in Japan...http://www.koden-electronics.co.jp/eng/ ... index.html

Now the radar cable.  I cannot say for certain in regards to Koden, but I CAN say for certain in regards to Raytheon/Raymarine and Furuno.  On magnetron type radars (versus today's digital radars), the cable length is specified when ordered, and the radome is "calibrated" to that length of cable.  If the cable is shortened, the radome must be re-calibrated by an authorized factory tech.  Today's digital radars, which simply use an ethernet cable to transmit data, any length can be used.  Once again, an email to Koden is in order...

[SaltH2OHokie]

Now shouldn't NMEA 0183 compliant mean NMEA 0183 compliant, regardless of brand Bob?

[seabob4]

Now shouldn't NMEA 0183 compliant mean NMEA 0183 compliant, regardless of brand Bob?

That's correct Ryan...in the concept of what data can be communicated between units...the "sentences", so to speak.  But GPS is GPS, regardless of what communication proticol is being used.  It's how the unit receives the LAT/LON from the puck that is the issue.  Once a head unit achieves a fix, then the 0183 coding takes over to transmit that data to other 0183-capable devices, most notably, VHF radios for DSC functionality.  But the head unit first has to be able to receive and use that GPS signal...which has nothing to do with 0183, 2000, or whatever...

[seabob4]

Ryan, the best "for instance" is Raymarine.  Their head units must use a Raystar 125 or 130, they will not recognize a Garmin, Lowrance, H-B, or anyone else's antenna.  This ensures you buy their antenna, and if you've ever priced used Raystar's on ebay, well, there's a reason they are up there, as opposed to a used Garmin GPS 17, for instance.  

Of course, as I said above, once the fix has been achieved, then 0183 takes over in regards to distributing data to whatever NMEA device, made by whomever, you want to network with.

[xo4001]

Salt, Bob,

Thanks for the input and link
Send the question to Koden wait and see what they come back with if any

[SaltH2OHokie]

I'm with ya Bob.  The Garmin puck I bought was a GP17 followed by some letters if I remember correctly. Fed a Furuno, a S-H and a Garmin.  I didn't even think twice about brands...reckon I was fortunate that my setup meshed.

[xo4001]

Just get a reply from Koden what is now Si Tex

You can shorten the wire but may have to do some adjustments to trigger delay (timing) for accurate target distance but that should be it.
Yes you can use a puck antenna as long as it outputs NMEA 0183.

So all seems to be very simple

[seabob4]

I'd go with a Garmin puck...

[xo4001]

Looking at this one
Garmin GPS 19x HVS Receiver NMEA 0183
What you think?

[seabob4]

Fine by me.  Looks like GPS City has it for $166, free shipping...http://www.amazon.com/Garmin-Next-Gener ... B0089YMO76