My experience is that I've never had a drop-out with the 12 channel receiver
(Garmin 195, installed with the integral antenna at the top of the panel).
The firewall also has spray-on RFI shielding.
Duncan McF.
----- Original Message -----
From: "Rob Housman" <rob@hyperion-ef.com>
Sent: Tuesday, February 05, 2008 11:40 PM
Subject: RE: Europa-List: GPS antennae siting
>
> With the GPS constellation's orbits inclined at 55 degrees from the
> equator
> those of us in the northern hemisphere will find the satellites generally
> toward the southern sky. This is much more significant in northern Europe
> (London 51 29' N, Paris 48 49' N, for example) where the satellites are
> near (or below) the southern horizon most of the time. I suspect that
> eastbound and westbound flights will get better reception than northbound
> and southbound flights if the antenna is within the panel since both the
> crew and the engine will tend to shadow the antenna.
>
> Can anyone confirm or refute this hypothesis from in-flight experience?
>
>
> Best regards,
>
> Rob Housman
> Irvine, CA
> Europa XS Tri-Gear
> A070
> Airframe complete
>
> -----Original Message-----
> From: owner-europa-list-server@matronics.com
> [mailto:owner-europa-list-server@matronics.com] On Behalf Of William
> Harrison
> Sent: Tuesday, February 05, 2008 2:43 PM
> To: europa-list@matronics.com
> Subject: Re: Europa-List: GPS antennae siting
>
> <willie.harrison@tinyonline.co.uk>
>
> Thanks, David and everyone. Presumably, as well as avoiding the
> shielding effect of the crew, antenna height relative to the engine
> and the metalwork in the panel itself would help comms with
> satellites close to the horizon.
>
> On our last French trip in October, (Paddy Clarke, Alasdair Milne,
> myself) we all lost GPS signal at various times as well. In addition,
> my "Old Faithful" 295 died peacefully (so peacefully that there was
> only a frozen display with no explicit warning that it was
> meaningless - charming).
>
> Cheers
>
> Willie
>
>
> On 5 Feb 2008, at 21:57, David Joyce wrote:
>
>> <davidjoyce@doctors.org.uk>
>>
>> Willie, It sounds from your replies that top of instrument panel
>> gives OK
>> results, but I wonder whether the fuselage top between your doors
>> may give
>> even better results, as I can imagine that pilot and passenger will
>> blank
>> some satellites for a panel aerial in some situations. Everyone I
>> have flown
>> with on the trips I have done in Italy have lost GPS signal at
>> some point,
>> but I never did. I had tended to put this down to superior
>> performance of my
>> Garmin 295 as opposed to most people's Skymaps, but it may be
>> because I have
>> my aerial above head level. The cable supplied by Garmin and by Blue
>> Mountain is plenty long enough to reach there, and otherwise gets
>> coiled up
>> behind the panel where it could possibly be subject to electronic
>> interference. Regards, David
>>
>>
>
>
>
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