FLARM - No GPS

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.


--
Dan, 5J

Thanks Martin,

As I said earlier, the unit did not generate an igc file yesterday which
I assume was due to no GPS lock. Since installing the unit about a
month ago, I've had only one flight near enough to another equipped
glider to produce an alert. I submitted that file to the range analysis
tool and the result was about 6 km around the front and sides with
practically nothing behind. That's reasonable considering my all carbon
fuselage and wings.

Next time I get to the airport, I'll have a look at some of the logs to
see what the GPS lines look like, but I don't thing that's where the
problem lies. The unit never locates any satellites. I'll also try it
with the ADS-B antenna removed from the proximity of the unit.



On 11/24/2016 2:17 PM, Dan Marotta wrote:
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.



--
Dan, 5J

Long shot, but when you fabricated the aluminum plate bracket, how did you fix it to the PF unit? Don't know if it came with mounting pts, but maybe steel bolt heads might cause some interference if you went through the case. Power input is OK, right?

A good question. I used very short brass instrument screws to affix the
unit to the aluminum plate. Power is fine unless there's a state other
than on and displaying "0 Satellites" and not on. Maybe the aluminum
plate is the cause (as I've only flown it once while attached to the
plate), but that goes against all I know about ground planes, etc.

I'm going to the airport today and I'll try these things in order after
moving the glider outside:

1. Power the unit up and wait to see if I receive any satellites, if
not then,
2. Move the ADS-B antenna, if not then,
3. Remove all antennae and replace with rubber duckies, if not then,
4. Remove the unit from the glider, use rubber duckies, install
batteries (now the aluminum plate is removed), if not then, WHAT?

I'll look at the .igc files that I've previously downloaded and see what
I can find about the internal GPS (I'm disappointed that it's not an
aviation grade GPS per the FLARM manual). Reload the firmware (which
was updated last month). Report back on my findings.

Sheesh... My MRX PCAS worked perfectly from day one.

Dan

On 11/24/2016 3:36 PM, Duster wrote:
Long shot, but when you fabricated the aluminum plate bracket, how did you fix it to the PF unit? Don't know if it came with mounting pts, but maybe steel bolt heads might cause some interference if you went through the case. Power input is OK, right?

--
Dan, 5J