Bad CMaps?

[Sandero]

I am having a weird problem with my first chart plotter which is still in service - Horizon CP170 which uses CMap charts.

This summer the thing wouldn't get a fix and sometimes it would and then lose it after a hour or two. It was completely unreliable. I did all sorts of "ram clears" and tried with and without the chart cartridges in place and finally sent it back to Horizon.

The thing comes back... I insert the chips and connect up the wires and it still doesn't work. So I think it's got to be the antenna.

The thing does give the correct GMT and show satellites but it doesn't lock on and display a fix so it is definitely the same as when it was sent in for repair. They said there were some cold solder joints on the board. Yea right.

So when I call up and give them the bad news they tell me to do another ram clear, and try it without the chart carts in place. Apparently charts can go south on you and influence the software in the main device... yea right.

So I call up CMap and they tell me charts can go south on you and they are only guaranteed for a year so I am looking at 2 new charts which could be as much as $400. yea right. I was told to run a pencil eraser over the contacts as they might have contamination... yea right.

So this weekend I will attempt all the proposed "fixes". If it works without the charts it was bad charts, one or both cartridges. If it was the ram clearing the ram got messed up after it was bench tested as OK.. how does that happen?

Imagine if the charts are messed up? Even if I rippped on paper chart of spilled coffee on it I wouldn't be looking at $199 to replace it. If I have to I am going to be majorly pissed at CMAP whose cost is about $5 per chart I would guess. Lovely customer service approach.. ain't it.

And the old ones can be erased and over written either. Why don't they use media like cameras?

Oh and I told them the thing is hardly ever on and how many hours can I expect from a marinized piece of electronics. Mind you the LCD went south 2x in 7 years so far? My little plotter has been to the west coast more than I have!

The told me turning them on and off is not so good... yea right. Well my B&G have been out in the elements for 22 yrs and they still work and have never been repaired (some of them anyway)... and they have been turned on a off a zillion times.

Can you believe these tech support guys or what?




Stay tuned for the weekend installment of this nightmare.

[delmarrey]

I had (have) the same problem with mine. It was only on it's second season when it started the problem with acquiring. It could be just your almanac needs to reset. After leaving mine on for 24 hours it seemed to do better.

Check out this thread........................_/)

http://www.cruisersforum.com/forums/...ever-7041.html

[senormechanico]

I may be wrong, but I think the GPS/chartplotter only uses the chart cartridge to paint a pix of the spot where you are on the chart and has nothing to do with reception of the signal. In other words, if you can't acquire the satellites, it hasn't anything to do with the Cmap.

As Del said, the almanac might be the problem.


Steve B.

[Sandero]

Steve B, You are correct. The plotter will get a fix without the charts. But Horizon tells me that a bad chart can mess with the performance of the GPS.

I also believe that the GPS do downloads the "ephemeris" or almanac for the satellites and this takes some time. Without that info the position cannot be computed. New units take some time to receive this local data. Perhaps using it in far off places... might confuse the GPS as it tries to overwrite the old location's ephemeris.

Anyway, I will be doing what they told me and see what spins out. report to follow.

[delmarrey]

When I first bought my S.H. I was using it without the CMap until the one I ordered arrived, and it would acquire within a couple minutes without it.

I think there is something really fishy in their program, this summer it was doing fairly well compaired to last summer and the one before. If it gets really bad I'll just wrapped 'em all in a mains'l tight, with twice ten turns of a hawser's bight, And I'll heaved it over and out of sight, with a Yo-Heave-Ho! and a fare-ye-well , and a sudden plunge in the sullen swell, ten fathoms deep on the road to hell,
Yo ho ho and a bottle of rum!