Craig,
I also have the same ELT. However I mounted it just behind the
pilot. Just under the door rebate about 2" down. Why?, well that unit
can be removed from the a/c when you are down and take it with you. If
you have it beneath the rear deck, it becomes impossible to take with
you. Plus, at your yearly annual inspection, you just remove the two
straps and take it out and replace the "D" batterys. I went to an
electronics store and got a 90 degree antenna fitting so the unit could
be mounted fairly close toward the front. I mounted the antenna just
behind the rear bulkhead with the antenna pointed vertical. You need a
vertically polarized signal for best reception. (don't ask about an
inverted landing). I then mounted the antenna on a 1-1/2" square
aluminum tube. The tube was glassed to the bottom of the fuselage with 4
layers of bid. I had a 1/4" hold drilled on the side to bolt the ground
plane copper tapes to. The ground plane radials are necessary to produce
a strong signal. However, without a ground plane it still works. (note
the portable hand held radios by Icom ect. But your DAR may want the
radials so I mounted them (6) and put one layer of glass over them to
protect them. I folded the tapes over on them selves at the end that has
to be bolted to the aluminum tube so it would be stronger. I soldered the
fold over so the washer would not bread the tapes. Obviously do all the
mod's to the aluminum piece before mounting for the last time. The
antenna tip was supported at the top by reduxing a 1" dia. (thin wall)
irrigation tube to the back of the "D" removable panel. This way the
loading coil is contained with in the short plastic tube and can't flop
around. The mounting pads for the ELT unit were 3/8" thick plywood
reduxed to the side of the fuselage. These were about 1-1/4 wide and
about 3" long. Can not remember the exact size but you will see how to
match to the provided mounting bracket from the manufacturer.(this was
done a long time ago, memory short, old timers disease)
Jim Nelson
N15JN
(still holding at 42 hours, rain go away. For the last month, its
rained every weekend)
<craig.ellison2@verizon.net> writes:
> <craig.ellison2@verizon.net>
>
> All,
>
> I just received my Ameri-King ELT from AS and was going over the
> install instructions before mounting it under the baggage
> compartment. I was planning to mount the antenna on the back side
> of the baggage bay bulkhead in the horizontal position, but the
> instructions state that the antenna should be 20 degrees of vertical
> when the aircraft is in a normal flight attitude and if it is
> mounted to a non-metallic air frame, a supplementary ground plane
> must be installed.
>
> What happens if one were to mount the antenna horizontally?
>
> Is there a need for a ground plane in a composite aircraft?
>
> I would appreciate installation tips from builders who have figured
> this out already.
>
> Thanks in advance
>
> Craig Ellison
> A205
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