Plotter problem

[Micky]

Got a Lowrance 3500C chart plotter which works fine until i pass by a ship, then it freezes and stops working, A message then comes up with, Alarm...GPS NOT responding.

Anyone else had this problem.

 

[bob_tyler]

It could well be that the presence of the ship between you and one or more satellites makes your plotter think that they are turned off. It should recover once you are past the ship.

 

[CSFenwick]

Had exactly the same problem and also noticed it was when passing other ships. After some asking around it seems that the LGC-2000 antenna is a little too sensitive and any high powered radio interference (probably the RADAR on other big ships - particularly military/coastguard) will freeze it.

You need to momentarily de-power the antenna either by turning the switch off at the panel (at the unit won’t work as the antenna is still getting power) or unplugging the antenna and reconnecting it i.e. at the back of the plotter or the plug near to the antenna.

I called the UK importers - SILVA on 01506 419555/406288 and after initially trying to tell me I hadn't installed it properly they finally admitted they’d had ‘a few’ complaints of this type and were awaiting some new antenna's with better shielding from the US. They said they'd replace my antenna with a new one when they had one (it was mid May when I spoke to them and they said a few weeks) but expected me to pay P&P and I'd have to send them my current antenna before they'd dispatch the new one. Wasn't too impressed with having to pay another £5 or so in postal charges and be without a plotter whilst they do a swap. Lowrance should have tested them properly before they sold the product!

Having said all that I'm very pleased with the plotter itself and now I have my boat back home (Conwy) where there are far fewer (none?) passing big/military ships with powerful RADAR's I haven't had the problem happen at all. If you’re in an area where you’re seeing a lot of problems (The Solent seems particularly bad if the 4 weeks I was there earlier this summer was anything to go by) then I think you should call Silva and get a replacement antenna. If it’s only happening once in a blue moon then the fix’s above instantly brought mine back on-line.

Good luck!

 

[Micky]

CF1, many thanks for that info, that's exactly what happened, it was a military ship leaving our local dock that first started the problem.
All was OK until a week later when we past close by another ship entering the docks and the plotter stopped again.
I restore the unit once it has locked, in the way you describe
by isolating the power.

So it's the antenna shielding at fault.

I agree, Lowrance should have tested them properly before they sold the product!
I purchased mine locally and since we are often close to large ships in our area i guess this will be a regular occurrence, so will be back tomorrow expecting an upgraded unit ASAP.

 

[SolentSnowgoose]

Gents

I fear I may be the bearer of bad news.

I am now awaiting replacement of a second Lowrance GPS unit which has failed permanently after passing close to vessels operating Radar.

These were not powerful military Radar, one was a 2Kw unit on a small motor cruiser which passed a few feet away in a harbour entrance, the second was a small sand dredger in a lock in France.

Prior to these I have had the occasional loss of comms which was solved by powering down and back up and just prior to the last failure Silva supplied a software fix which was intended to recover the comms automatically.

I have triple checked the installation to make sure all the shields are connected as per advice from Silva/ Lowrance but the unit just seems very sensitive to incoming Radar

The only practical saving grace is that I have a very trusty old Garmin 12 which ( touch wood) never misses a beat ( fix) and have now wired the NEMA output from the Garmin 12 to the Lowrance plotter so that I can use the several £100 of Navionics Charts in the plotter unit which would otherwise be useless!

I am in correspondence with Silva about the obvious lack of testing but as far as GPS receiver reliability is concerned I think I can see a pretty clear lesson here !!!!!

If you have a Lowrence GPS unit then turn it off if you are near any other vessesl which might just operate radar otherwise it may get fried permanently !!!!!!

Suggest you wait till end of season and the go close alongside something with radar running and then send the fried unit back for replacement, by then I should have completed testing the product for Lowrance !!!!

 

[duncan]

Interesting, and of course cause for concern.

In and around Poole I constantly pass very close to craft operating radar - the Condor Vitesse as an example - as well as the military radar operated on the Lulworth firing ranges - and have yet to experience this problem.

Time will clearly tell. Silva clearly need to get their act together a touch though - as an absolute minimum I would expect a physical 'swap' at a retail outlet that suited me geographically.

 

[Bergman]

All of which poses an interesting problem if you find yourself in a patch of fog.

You can have the radar on and know whats going to hit you but not whereabouts you are.

Or you can know where you are but not whats going to hit you.

Hardly an ideal situation

 

[duncan]

hadn't thought of it in those terms - I have radar, in use, right next to my Lowrance antennae..................

 

[Sans Bateau]

I'll second what duncan has said.

I bought mine in Jan, so this is a 'newer' one. I have had no problems like those experienced.

It has been on almost constantly for two weeks with many ships and boats passing.
We came all the way across the channel on Sat with radar and 3500c working without a problem. We passed many ships both large and small in the CI's and France.

I know some people have also had tide issues, not for me, unit set to meters all readings including the little bar icon, all in meters.

Mine is running V1.6 software.