ICOM M 802 SSB Install Part 2: GPS connection

[wrwakefield]

Originally Posted by muttskie

Thank you all for your helpful comments.

I have purchased the Dockside Radio GPS data cable and will connect it to the Vesper Vision's NMEA0183 GPS data output.

The Vesper specs are very clear about it's ability to output, via NMEA0183, NMEA2000, WiFi, and USB, GPS position data. As I am allergic to NMEA0183, it will be my ability to figure out the proper connections that will be the weak link.

I would normally have the Vesper Vision on all of the time and it has it's own dedicated Vesper external antenna, so I wouldn't rely on the other GPS receivers on my NMEA 2000 network for position data. The Vision always displays position data, regardless of the mode it's in.

Also, I might include the ICOM 506 VHF into the Vision's NMEA0183 GPS connection. This would negate the need for powering up the NMEA2000 network to provide the VHF with position data.

If this doesn't work ( though I don't see how it couldn't ), I'll buy another Garmin handheld.

Bill

Hi Bill,

Your proposed solution will work. I do the same for the reasons you cite, only tapping my Vesper Watchmate 850 [the model prior to the Vision...]

We also have 3 other compatible sources of NMEA 0183 GPS data which I can manually rewire to if the Vesper ever failed, but unless I install failover switches, this would not be viable in an emergency...

In case you don't already have the separate DSC Rx antenna [looks like a VHF masthead antenna but tuned to the DSC Rx freqs] required for emergency DSC comms with your 802M, Dockside also sells that in a kit for about the same cost as what I could put together myself... [I have no affiliation nor incentive for recommending Doskside other than being a satisfied customer. There are likely other sources as well...]

Best wishes completing your project.

Cheers!

Bill

[ka4wja]

Bill,
Looks like you got it all figured out...it should work fine...

BTW, you make NMEA 0183 sound awful....yes, it's a "one-way" data stream, but you only need one-way, and it's only two wires...I haven't a Vision to look at, but if it's like my Watchmate, it have a clearly color-coded wiring diagram....take NMEA + and - out, to the M-802 NMEA cable + and - in, and you're done! Easy-peasy!

Fair winds..

John

[smac999]

the garmin 19x is still available in nmea183. just put in one today for a decated 802 and vhf feed on a boat. GPS powered from VHF breaker. so his nav can be shut off and still have gps on the radios. the seatalk to 183 adapter it was previously using for the vhf would not give a GGA output to to the ssb.


the vespar 850 only has one nmea 183 output. if you're using it to feed AIS data it'll be 38,400 and you can't feed the radios. though if it's n2k to nav gear then you should be able to change the nmea output to 4800. the above boat also had an 850 but was feeding the old raymarine with 183 AIS data so could not use it to feed radios.


I do not know why the 802 uses a BNC for gps serial data. its' really stupid.

[muttskie]

Originally Posted by smac999

the garmin 19x is still available in nmea183. just put in one today for a decated 802 and vhf feed on a boat. GPS powered from VHF breaker. so his nav can be shut off and still have gps on the radios. the seatalk to 183 adapter it was previously using for the vhf would not give a GGA output to to the ssb.


the vespar 850 only has one nmea 183 output. if you're using it to feed AIS data it'll be 38,400 and you can't feed the radios. though if it's n2k to nav gear then you should be able to change the nmea output to 4800. the above boat also had an 850 but was feeding the old raymarine with 183 AIS data so could not use it to feed radios.


I do not know why the 802 uses a BNC for gps serial data. its' really stupid.

Thanks, smac,
Helpful information.

[jr_spyder]

Very useful thread for me as I'm trying to solve the same problem right now. My older ICOM VHF radio receives NMEA0183 GPS info just fine from my chart plotter, but the new M802 doesn't. They are wired the same way and I've tried various connections. I've learned two things from threads on this topic - the M802 is finicky about this, and it would be far better to have an independent GPS data source anyway (I certainly agree).

My future research led me to find an independent GPS antenna made specifically for the M802 from a German company called Lunatronic. Here: https://shop.lunatronic.net/produkte...uct-8546710997 See the bottom of the page.

Has anybody tried this? Looks smart, but not cheap.

I know a handheld Garmin GPS is cheaper and gives other benefits, but I like the absolute simplicity of this. Install it once and never fuss again (if it works).

Thoughts?

JR

[SoonerSailor]

The Garmin GPS 19X might fill the bill for you at a lower price.

Chip

[jr_spyder]

Thanks, that's perfect. When I saw the model suggestion earlier I thought it was another handheld unit. This independently operated GPS antenna is obviously a good choice. I like that it even comes with a mounting frame to install it inside under the deck. All good.

JR

[jr_spyder]

More on this story. While I was searching around for a solution I came across a unit that sounded right but I could't find any details. I emailed the manufacturer and got some great support, including a wiring diagram. I wanted something small and simple and liked this. And it's half the price of others.

It's widely available online. Here it is on Amazon https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

[IMG][/IMG]

[IMG][/IMG]

I snipped off the automotive type connector on it and put on my own BNC connector and a fuse in the power line. It worked immediately giving the 802 UTC time and location, even with the antenna inside the boat. I've now mounted it on the underside of my deck (foam cored fiberglass) and powered it on the SSB circuit. Easy! I'm very pleased.

For the record here are the wires:
Red - 12v +
Black - 12v -
White - NMEA 0183 Tx+
Green - NMEA 0183 Tx-

There is a mystery that continues however. As I said in an earlier post my current GPS source (B&G chartplotter) for my ICOM VHF did not work for the SSB. And this Faria unit that does work for the SSB does not work for the VHF (I wish it did). All the required specs in the radio manuals are the same. So I still have to use both, and have a non-ideal source for the VHF. All devices supposedly use GGA sentences.

That said I have to consider this problem solved and move on to others.

JR

[Sea Angel1]

Hi John,

I'm installing an Icom M-802 and you advised using a dedicated Garmin GPS. Finally I got a Garmin GPSMap76S. This GPS has 4 Connections:
+ and - 12 V (evtl. getting from the ICOM Acc Connection).
And a Data in and Data out.
Now is my question: The ICOM has a BNC plug for the position Data. That means a center pin and a outside braid (coax). Should I connect the Data out (GPS) to the centre pin, and the outside braid to the - (ground)?
Surely I loop the coax thru a ferite on both ends.

2. I wired a separate, twisted, 12 V charge cable from a dedicated battery.
But it passes 12" ( 30 cm) from my steering electric compass. Will that influence my autopilot?
Should I mount some ferrites (1) on the both ends of the charge cable, (+ and -). total 4.
3. I used in general ferrites , manganese- zinc. I hope these are better than the Nickel-Zinc ferrites, because e are in the lower to middle frequencies, correct. I no where read this, though.

thanks for your help and always good comments.

[ka4wja]

Sea Angel,
1) You will be using only 3 of those wires from the Garmin....
+ Data Out (NMEA + Out)
+ 12vdc (positive 12 volts DC in)
- 12vdc (negative 12 volts DC in, AND ground connection for NMEA Data in and out)

From the Garmin, you will use the negative 12vdc (- 12vdc) connection as your ground, for BOTH the 12vdc power input and the NMEA - output.

You will use the NMEA + output to the center pin of the BNC connection...and the - 12vdc / ground connection as the shield (or outer shell) of the BNC connection (as well as your negative 12vdc)

Making these data wire connections directly to a BNC connector is damn near impossible, so I recommend using a short length (how ever long you need to reach) of small coaxial cable (such as RG-174 or RG-58) on the BNC connector, and then simply connect this coax center-conductor to the NMEA + OUT of the Garmin, and the shield of the coax to the negative - 12vdc / ground connection of the Garmin.

Be sure to set the Garmin data output to NMEA (NMEA 4800) and it will work fine....

{I don't use the M-802's acc connection's 12vdc to power my Garmin, as that would then only allow the Garmin to run on ship's power when the M-802 is actually on, which is only a few hours/day...and therefore it would not be available to send position data to my VHF-DSC radio (which it does) 24/7, nor would it be useful as a secondary (or primary?) GPS device on-board (which it does)....
I have my Garmin powered directly from a circuit breaker on my electrical panel....but, it could easily share a breaker with some other device (such as VHF radio ??) that you'd be using 24/7...}

As for ferrites, yes I have used them here....but probably unnecessary!



2) As for your 12 volt charger cable???
Placing ferrites on that will do nothing to help your autopilot compass!!
Not sure I have a grasp of what you're describing....but, the magnetic field created by the current running thru these wires cannot be reduced by ferrites at all (that's not what they are for)....

The only ways to avoid high-current wiring from effecting your compass are:
a) distance....farther away the better...
b) lower the current....the lower the current the better...
c) twisting the wires....theoretically doing this is supposed to cancel the magnetic fields, but it the current is high enough or the wiring close enough, you might still have issues...
{you'll notice the small extremely-low-current wiring used in binnacle lights is always twisted, as to not adversely effect the main steering compass....but remember these currents are very low, and the wiring is very close to the compass....}



3) As for which ferrites to use....I thought I answered this in December....it is all about the "Mix" (or "type"), not about whether nickel or manganese....
Please have a look here:
http://www.cruisersforum.com/forums/...ml#post2287912

The short answer is to use Mix 31...

For our purposes (HF radio RFI), use Mix 31, Mix 77 (used to be named Mix 73), or Mix 75....
{note, for VHF RFI, Mix 43 is best....but Mix 31 does still work...}

In the US, you will find most "split-beads" and "clamp-on" ferrites for sale, for RFI suppression to be Mix 31 or Mix 77 (or labeled Mix 73)....and as far as I know, this is also the common retail sales practice in Europe, but I'm not sure about in Asia???


I hope this helps...

Fair winds.

John

[Sea Angel1]

Hi John,

ok everything clear,
Will do the wiring up acc yr description and

I got the correct ferrites for the frequency range

About the 12V lines, (too) close to the elctrical compass?, I will check if there is any influence on the trials coming spring.

So far thanks for yr fast reactions.

Theo
S/Y Sea Angel,
moored now in Sicily (Italy)

[carlwk3c]

Originally Posted by jr_spyder

Thanks, that's perfect. When I saw the model suggestion earlier I thought it was another handheld unit. This independently operated GPS antenna is obviously a good choice. I like that it even comes with a mounting frame to install it inside under the deck. All good.

JR

The Garmin outlet store has the GPS18x for cheap. (Get the LVC version with bare leads)
https://g.factoryoutletstore.com/details/41008/41865