I have two GPS antennae, one for the Dynon EFIS and one for the ClearNav
vario. They are on opposite sides of the Stemme's panel, about 2 feet
apart. There is no external antenna for the PF Portable. It worked
just fine on all flights previous to the one yesterday. I think my
ADS-B antenna is closer to the PF Portable unit now than it was before,
maybe 2 inches. Might that be the cause?

On 11/24/2016 11:46 AM, wrote:
Are you using multiple GPS antennas? They can influence each other when in close proximity.


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Dan, 5J