GPS can not find satellite

A

azfred

Filing Flight Plan
Joined
Jan 28, 2015
Messages
4
Location
Arizona
Display Name
Display name:
azfred
I have an Garmin GPS 150 that was used some years back in Florida, but now here in Arizona it starts up but can not find any satellites.The antenna is fine.
The Garmin service dept. is of no help.
What can I try?
 
sounds like it needs a new almanac -

PS: I have no idea how to install an updated almanac in a GPS150 . .. but if it does not know what time the sats think it is based on their orbits or where they need to be, then it cannot compute the present time delta from sats it can see. . . . and thus does not 'see' any satellites cause it does not know it should be looking. I know that makes no sense, but thats how the clocks determine your position.
 
Last edited:
Having moved it that far across the country it will take it quite a while to find itself again. Place it in good view of the sattelites and just let it run. It may take hours but if it is good then it will eventually lock on. Had this happen with an Avmap on a long trip and as I recall it took about an hour but it did lock on and was perfect after that.
 
No idea how to help but welcome to the forum!
 
It may take a very long time, just turn it on in the open and let it run 30 mins or more.
 
I have a Garmin 76s that had the same problem. It had not been used in years.
New batteries and put it out on the back fence with a clear view of the sky.
Checked it about 3 hours later, it had found itself and downloaded a new almanac.
 
Thanks for the advise.
I left the GPS powered for 30 minutes, when it found one satellite and after moving the plane out of the hangar lost it again.
Next I will try again for a longer duration and change the memory battery.
 
This happened to my old Magellan back up GPS. I thought it was toast, and just left it on the glareshield for an hour. When I grabbed it again, it found the location and was tracking just fine. Thinking back, the last time I had it powered on was in Indy, and I was currently in NW TX. Needs a good field of view for as many sats as possible.
 
If I wanted to use my old Garmin 45 (now we're talking old, I got that for Christmas in 1994) I'd just put it out on the railing of the deck and let it run (with a new set of batteries). It would take a while, but eventually it would get what it needs and fire up. Now, given the GPS in my Nexus 7 and in my phone, etc., why would I?
 
I recall the older Garmins having a menu selection to find satellites from current location as opposed to the automatic assumption that it was where it was when last turned off. Try that.
 
Geico266 said:
It may take a very long time, just turn it on in the open and let it run 30 mins or more.
Click to expand...

The GPS is working again, it took 3 hours to find the satellites and now it only takes about 30 seconds.
azfred
 
The GPS is working again, initially it took 3 hours to find the satellites and now it only takes about 30 seconds.
Thanks, azfred.
 
azfred said:
The GPS is working again, initially it took 3 hours to find the satellites and now it only takes about 30 seconds.
Thanks, azfred.
Click to expand...

For future reference:

The GPS needed a new almanac like comanchepilot mentioned. The GPS will download this data from the signal it receives from each satellite. This can take anywhere from 15 mins to several hours depending on a variety of factors. The older GPSs typically take longer to acquire this information. Until then it can hear the satellites but it has no idea "where" each satellite is located in the constellation. It's basically playing Marco Polo.

As you noticed once it had the current almanac it was able to compute its location within seconds.
 
Ghery said:
If I wanted to use my old Garmin 45 (now we're talking old, I got that for Christmas in 1994) I'd just put it out on the railing of the deck and let it run (with a new set of batteries). It would take a while, but eventually it would get what it needs and fire up. Now, given the GPS in my Nexus 7 and in my phone, etc., why would I?
Click to expand...

My father has one of those units which he still places outside every few months to see if it works. I remember playing with it when I was little. Those things are built like a rock.
 
You must log in or register to reply here.
Back
Top