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HAGUEY247
10-04-2009, 08:24 AM
Hi,

My GPS worked the very first night (run at about 6pm) but since then (two weeks) it is unable to locate satelites. I've unpdated the software and reset satelite cache data etc.

Strange thing is at midday it picks up satelites in about 20 seconds.

Any tips appreciated.

GBMOD11
10-05-2009, 08:55 AM
As long as you have a clear view of the sky you shouldn't have any additional difficulties acquiring satellites at night. At this point you might want to try a master reset (mode and power), clear all user data (so be sure to back it up first), then allow 20+ minutes to acquire.

gbmod11

HAGUEY247
10-08-2009, 04:08 AM
Tried the master reset, went outside tried to aquire satelites eventually gave up and went for my run regardless (6pm).

Took it to work (20km from home) performed a master reset and left it outside (12pm) and it found the satilites in approx 20m.

Came home that night went outside before my run turned it on and again eventually gave up after 15m and went for my run anyway.

Giving it one more try going to master reset it and leave it outside 1hr before my run to see how it goes.

If that fails I'm returing it.

Can you explain the seeking process. What I thought should happen is it needs to aquire 3 satelites so it can triangulate position. What it appears to be doing is scaning for many many satelites and failing. What is the difference between an empty bar and a full bar in the signal strength display? It seems to at least find some at night but just sits theres talking to one forever with an empty bar / timing out and retrying?

GBMOD11
10-08-2009, 07:16 AM
What's odd is that the device finds satellites sometimes, but not all the time. Usually it's all or none. The empty bar means it's not acquired satellites yet. You can check satellite progress in more detail: Main Menu > GPS > Satellites.

Check your firmware and GPS chipset please (Main Menu > Settings > About Forerunner). Current firmware is 2.60 and GPS 2.10. You may need to update device firmware (http://www8.garmin.com/products/webupdater/howtoinstall.jsp).

gbmod11

HAGUEY247
10-10-2009, 02:49 AM
Thanks for the reply gbmod11.

As mentioned in my first post I have firmware 2.60 and GPS 2.10.

I think you missunderstood what bar I was referring to - I was referring to the bars in the satelite signal strength display. Sometimes they are empty and sometimes they are full (as in colour) I'm assuming its something to do with talking / connecting during the locating satelites process.

Can you explain what I should expect as it may be my expectations are too high. What I thought should happen is the first time I turn the watch on / reset cache / master reset it will need approx 20m to find and cache satelites and from then on it should take approx 30s to find them when switched on.

Mine seems to want to take 20m everytime I turn it on (same location) and I cant be bothered waiting 20m before every activity.

WAMBLE
10-10-2009, 04:56 AM
Thanks for the reply gbmod11.
Mine seems to want to take 20m everytime I turn it on (same location) and I cant be bothered waiting 20m before every activity.

My 305 used to take a while sometimes (5 or so minutes) and more if the weather conditions were bad (eg. stormy or windy) or there were lots of trees or tall buildings around. Going through the middle of Sydney CBD with the 305 always meant losing the signal.

The 705 is better, but sometimes it's still a few minutes to sync. I view it as an opportunity to stretch and otherwise prepare. Turn on your GPS and let it sync while you put on your running shoes, check your water, etc.

HAGUEY247
10-12-2009, 03:37 AM
Thanks for the reply Wamble in Brisbane myself.

What I noticed tonight as I sat outside in the dusk / dark for ages was that it had up to 8 satelites detected in the satelite signal strength display however it could not seem to make more than two connections (I'm assuming dark bars are connected and empty bars trying to connect). It gets to 90% locating satelites and drops down continuously which I'm suspecting as it cant connect to a third (its my understanding GPS needs a minimum of 3 to triangulate).

This day work / night no work thing is bizarre - going to check how many satelites it detects at midday tommorrow.

HAGUEY247
10-19-2009, 08:12 AM
Seems my expectations were too high - it will eventually pick up satelites after dusk it just needs the 20-30m detecting satelites every night.......

Some how I'd been lead to believe after it first caches satelites in a location the process would be much shorter however if the watch is turned off for an extended period its goes back to the full 20-30m detection process......

BERTEDDIE
10-20-2009, 07:27 AM
My understanding is as long as the watch has had a satallite lock within the last three days then it should lock fairly quickly (ie 30secs or quicker). If its been more than three days then it takes longer, in my experience it can take up to 2mins, but I cant remember it taking any longer than that.

This is at both day and night, not that that should make any difference, so thats still a puzzle.

If yours is taking 20-30mins each time then I would suggest talking to Garmin Support because that is waaaaay too long.

FULMAR2
10-21-2009, 10:12 AM
For a while I used to use my GPS at night, and I couldn't figure out why it wasn't working. It took me a really long time to make the correlation - but I was using an HID headlight whenever I was out at night. I finally did a test - went to the satellite page, and turned on the backlight. Without the HID helmet light nearby, signal was perfect by day and night. But when I brought the helmet light nearby, the satellite signal would drop - to the point of the message "Lost Satellite Reception" being displayed. This may not be your problem, as it sounds like you are running, and I am not aware of any HID lights for running - but I thought I would mention it.

NDURANCERIDER
10-21-2009, 10:44 AM
I had a weird experience once. This was with a car unit and one of the PDA units. We were driving through SC and when we had one particular music station tuned on the car radio, both units dropped satellites. If we tuned to a different station, both units picked up satellites again. It was the freakiest thing.

April