GPS slow to acquire satellites.

[BigE]

Looking for some help , I'm not really a technical person so it could be some thing simple.

I have had my gps out of the boat for a while (6 months at least ) I have change it from a gimbal mount to a flush mount and it is taking forever to acquire satellites like 20 mins or so once its locks on it's fine but it takes forever and doesn't inspire confidence.the unit is 3yrs old and has been performing well up to now.are there any settings to change when flush mounting a Chartplotter /sounder combo.

My unit is a GPSMAP 750s (touchscreen) any one got any ideas? Anyone know Garmin products very well.

Thanks BigE

[scottar]

You need an external antenna. What is basically happening is that the signal strength is down enough that the unit is not really happy to use the satellites it is seeing. From memory they use a standard antenna - used to cost about $100. Think GA30 was the model number.

[scottar]

Looks like new model is a GA38. Check with a good Garmin dealer as to suitability.

[BigE]

Thanks Scottar

will try and get one this week. might try pulling it out of the dash and see if it acquires any quicker when nor flush mounted in the dash.

PS .. if i die i want to come back as one of your worms.

BigE

[tunaticer]

try for an update first......if it is anything like my car gps it needs an update every 2nd yr

[chocolatemoose]

750s did get funky with gps's over time "that and touch screen issues" still brilliant little unit. depending on its location moving it indash could be interupting decent reception like scott suggested.

external antenna is the go "always worth running updates first" its a groovy coax external. nice and easy. no backbone or wiring to deal with

i found a few in a rummage this morning funny enough

[BigE]

Chocolate moose PM ed ya

BigE

[Feral]

Not surprising it would take a long time to get a signal first up after being so long with out connecting to the grid. The Almanac's (records of where all the GPS satellites should be at a given time in the sky) are only good for 180 days or so. Once it has expired the GPS must download the full almanac to allow it to connect to the grid again and function. It has to first connect to at least one satellite to do that, and as it has no idea of where the satellites are, it is pot luck finding one as it just has to keep cycling through all the possible satellites it might be able to find.

If it happens again, or continuously, I would think it is not holding the information in the unit, dont know the model concerned, but it could be something as simple as an internal battery is kaput. A GPS that is only 3 years should have no issues reading through a boats structure, unless it is aluminum, and even then I'd still be surprised. even my little Etrex still holds signal when tossed in the boot of my car. My oldest GPS units used to lose signal under heavy cloud.

Quick check would be to ensure it has a continuous power supply connected and see if that helps.If not, and it still takes up to 20 minutes to get an initial connection- just turn it on before you leave the driveway, once it is connected it should be rock solid.

I have an old map276 I use in my boat that is that old it can not read the almanac from the satellites, it was preprogrammed with it, and the data held internally has long since expired. It takes up to 20 minutes to connect if I have not used it for a few days. I just turn it on when I leave home, by the time I get to the ramp it has a lock and I have no issues with it running solid all day.

[BigE]

thanks Feral

[scottar]

Thanks Scottar

will try and get one this week. might try pulling it out of the dash and see if it acquires any quicker when nor flush mounted in the dash.

PS .. if i die i want to come back as one of your worms.

BigE

Worth trying it out of the dash just to confirm. If it's still slow it could well require an update or possibly an internal battery - they will usually lose their waypoints if the battery is shot though. The change in location could possibly be bringing two factors into play. The first is signal degredation from the actual flush mounting - glass in itself isn't generally too bad (unless it's ridiculous thick) but timber will definitely attenuate the signal as will large expanses of metal. The other is interference - seen plenty of interference issues due to proximity and sometimes orientation of other LCD displays - some bad enough to stop a unit working all together.

[BigE]

thanks scottar ,,,, console is pretty thick where the unit is mounted over 1/2 inch , will pop it out on the weekend and fire it up to see if it make a difference, I think it's due for update as well.

BigE

[BigE]

hooked up and external aerial ..... instant sat pick up on 9 sats ........ happy camper

BigE