An off the wall thought - you lose lock and signal during periods of
high-rpm (takeoff and climbout) and low-rpm (landing), but mid-range
seems to work okay. Could there be some hypersensitivity to voltage
fluctuations that the 396 has? Voltage might also drop during
transmitting if there is a resistance in the bus supply.

You've moved the antenna, around and even switched back and forth
between powered external and stubs. If it isn't the 396 then what other
common denominators are there? (Even if it is voltage fluctuation, the
396 shouldn't be that sensitive -- none of your other avionics are.)



-----Original Message-----
From: Mike Spera ]
Posted At: Tuesday, July 04, 2006 14:17
Posted To: rec.aviation.owning
Conversation: Garmin GpsMap 396 - Flight Test
Subject: Garmin GpsMap 396 - Flight Test


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

Too early to reach a conclusion. As I said, I will try the Airmap 1000
and Apollo 920 side by side with the Garmin and see if I can isolate
it.

At least I don't feel quite so crazy since yours does it too. Funny
thing, I never mentioned any problems in landing in my post, but it
did
indeed almost lose its lock in both descents I made during testing. I
had maybe 2 sats at minimal strength for 30 seconds or so one time.
Another descent had the thing completely checking out for 1 full
minute
(no sats at all).

Thanks,
Mike



Thanks,
Mike