I inquired to Garmin Tech support about our problems and got the
following response about clearing the almanac. Probably worth a shot.
--Dan
========================
Problem:
I had a problem with satellite reception over the weekend. In
disucssing this with other GPSMAP 396 users, including one who recently
upgraded to firmware 3.20, it seems they are experiencing similar
problems as well.
(i.e. intermittent GPS satellite loss) I have a GPSMAP 195 and have
never had a satellite signal issue. Is this a known problem? Will there
be a firmware fix?
===============================
Thank you for contacting Garmin.
As the GPS uses a satellite almanac of data to track the satellites,
corruption of this almanac will cause the unit to drop the satellite
signals. To correct(erase) the almanac, turn the unit off. Press and
hold the OUT button while turning the GPS on. When the GPS powers on,
release the buttons and let it acquire the satellite signals to start
rebuilding the almanac.
If you have any other questions, please let me know.
Best Regards
===================
Thanks. Would this likely resolve intermittent outages, or is this
only in the case of being completely unable to get a satellite lock at
all?
--Dan
================
Thank you for contacting Garmin.
As the unit contains data on all of the satellites and cycles between
all ones available, corruption of even one satellite's data could cause
the unit to have brief outages as it cycles through the list.
If you have any other questions, please let me know.
Best Regards
Dan wrote:
By the way, this was with firmware version 2.8 which is what came on
the unit. I am planning to upgrade to 3.2 soon.
--Dan
Dan wrote:
I picked up a 396 on Friday and it was fine all the way from Phoenix to
Santa Fe, but lost it's sat signal during landing in Chandler....
Strange, but it seems I am not alone.
--Dan
wrote:
Mike Spera wrote:
30 seconds after take off, lost
the GPS sat lock. Took about 15 seconds to regain it. In the next 5
minutes, it lost lock several more times. I'm thinking, external antenna
is loopy.
Mike,
For what its worth...
I just flew my Arrow around the country and experienced the same
problem (with my brand spank'n new 396) that you described. Most of the
occurrences were in the takeoff or landing phase of the flight. I had
my old Lowrance airmap 100 on the copilot yoke and it never lost lock
once during the flight. The 396 was connected to the remote antenna
which was sitting on the glare shield, the airmap 100 was using it's
built in antenna.
-Bernie
My fly-about http://www.iperformax.com/flyabout/flyabout.html