Garmin GpsMap 396 - Flight Test

Mike Spera wrote:
snip
Not exactly confidence inspiring. This unit may be a bad one. It
happens, I just wish it were a complete failure instead of this
intermittent crap.

I'll report on its progress.

Mike

Funny you should mention this. My 396 GPS reception has been flaky
lately too. Normally, the stick antenna would give me 4-5 sats indoors,
which is pretty good, while the external (powered) antenna would lock 8+
sats at higher signal indications in the same location (understandable
since it has a preamp that's powered through the coax).

Shortly after I upgraded to firmware 3.0 or 3.1 (can't remember exactly)
I took a trip to SC and had the external antenna just completely crap
out on me. No sat reception at all. I replaced it with the stick and
that got me three sats...enough for 2D positioning.

I initially attributed it to poor satellite positioning (there are times
when all the sats are behind the aircraft and the aircraft structure
shields the yoke/glareshield area), but it didn't comfort me to realize
that the Garmin 430 in the panel was locked to 10 sats with signals
pegged high.

Just today, after upgrading to 3.2, the problem isn't as bad, but the
external antenna doesn't seem to be doing the same job as it used to.

The release notes for the last several releases mention that they've
been screwing with reception issues for the XM receiver, but I wonder if
they messed something up with the GPS component firmware.

So, who wants to open a case with Garmin? If I can find two seconds to
rub together, I just might...this thing WAS running beautifully in the
2.x firmware days. I'm almost tempted to downgrade and test my theory.

-Doug

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Doug Vetter, ATP/CFI

http://www.dvatp.com
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