Jeff,
The ground plane depends on the transponder antenna.
If building one yourself from braid wire like the com is done, yes one is n
eeded. If using an external antenna, yes of course. However:
If using a Bob Archer Model 5 or Advanced Aircraft Electronics (AAE), a gro
und plane is unneeded. I use the AAE exclusively because it is quick to in
stall, and works perfectly with any ADS-B / Mode S and require no ground pl
ane. I mount the transponder abeam the aft inspection panel. I put a bit
of a convex curve on the balsa support supplied and a bit of Redux and tack
with superglue until the Redux cures. Been holding fine on all my aircraf
t since 2000 so it must work.
The Bob Archer Model 5 is also quite good. It is larger and a bit cumbersom
e.
Place the com in the vertical tail works really well. Again I use the AAE
brand as it is bulletproof, easy to install and has little thickness. They
work with a BNC connectors either radial or tangential.
AAE Nav antennas I put across the curve just behind baggage bulkhead. Work
s fine, no VOR/ILS reception problems.
GPS antennas work well in the Europa panel. I have two in mine mounted bel
ow the top using a metal HAT Section Reduxed and or glassed to the top.
Garmin and Stratus supply a huge exterior mounted GPS that weighs about 2 p
ounds. I use them, because I have to, but don=92t like the weight. Both t
hese suppliers have sufficient metal in the base for ground plane and requi
re no extra ground plane but do take up panel roof top space. Plan well.
I do sometimes use an aluminum ground plane for the ELT antenna, but normal
ly convince the owner to substitute the external ground plane antenna for a
composite installation antenna . The AAE com antenna is fine for 121.5 an
d works with 406 but don=92t ask me how it works, Artex says it is OK. Che
ck with your specific ELT manufactuerer. The small whip antenna ELT manufa
cturers supply, works with a six spoke aluminum X on the base built inside
the aircraft. Just Google it and many of the manufacturers show how. A rea
l pain to put in, so you see why I go to the manufacturer and ask for a com
posite equivalent antenna. Personally for ELTs I prefer the EBC type as th
ere is no wiring. Mount to the baggage bay side and press on with the bui
ld. The time saved is worth the wiring and antenna mounting.
I never put an antenna external to the clean skin of the Europa. Therefore
, no aluminum foil ground plane is necessary.
Best Regards,
Bud Yerly
Sent from Mail<https://go.microsoft.com/fwlink/?LinkId=550986> for Window
s 10
________________________________
From: owner-europa-list-server@matronics.com <owner-europa-list-server@matr
onics.com> on behalf of Jeffrey Williams <jeffwill55@sbcglobal.net>
Sent: Friday, August 16, 2019 11:14:51 PM
Subject: Europa-List: Ground plane question...
et>
Maybe this one is for Bud Yerly, but anyone can chime in.
I am installing instruments in my Europa XS and was told all transponders n
eed a ground plane. My research indicates a 12 inch circle of thin copper o
r aluminum will do, but that the ground plane and the antenna should be out
side the aircraft so things like the engine and other metal stuff doesn=92
t interfere with the signal. I have a Mode C and a Mode S to deal with=85an
d a GPS and Comm antenna too, but those don=92t seem to need a ground plane
. I am being informed that these antennas need to be at least 40 inches apa
rt as well. Also, I have been told that putting the antenna itselfoutside t
he aircraft and the ground plane inside is a bad idea that screws up the si
gnal.
Is any of this correct? What did you guys do?
Regards,
Jeff Williams
|