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Graham Singleton wrote:
Martin wrote> 
> >>It has occurred to me to wonder what builders are doing about antennas
> within the structure for VHF nav & com and ADF.<<
> 
Graham replied>
> VHF antenna is built into the fin. No one bothers with ADF any more, doesn't
> work hardly in glass airplanes anyway. VOR can be built in easily but also is
> almost superflous, until the GPS packs up, of course.
> Graham
Such faith in GPS !    If you lived where I do you might be a little less 
confident
!   VOR and 
ADF are needed here - try finding a small island in a lot of sea  by pilotage 
when
the GPS dies 
on you !  In some places there is only ADF - the Grenada VOR has been 
temporarily
u/s for four 
years or so and broadcast stations can be a very comforting replacement for a 
beacon
in need.  
Personally I should never want to fly without ADF and VOR in the aircraft and I
normally 
supplement this with my own GPS and handheld nav/com.
Yes, the obvious place for the com antenna is the fin - where do you put the nav
antenna (which 
is normally horizontal)?   What materials do you use for  the antennas   ?    I
have a feeling 
that a dipole made of thin copper wire would be likely to suffer as the airframe
flexes and would 
eventually crack and fail.   Perhaps using braid would be better ?
---From the way you write it sounds as though antennas are a foregone 
conclusion and
perhaps you are 
all using some commercially available item - but I tend to roll my own and 
thought
that others 
might also !
Regards,
Martin
Martin W. Berner, 26 Mayfield Road, Valsayn Park, Trinidad, The West Indies
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