Cruising Helmsman – June 2017

(sharon) #1

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Cruising Helmsman June 2017

The exposed f lexible cable loom can be
tidied using a fabric cover.

LIGHTNING
Those exposed overhead electronics
made it rather easy to disconnect them
from power, antennae and data cabling.
Paranoia perhaps, but having endured
some terrifying and prolonged electrical
storms under convergence zones, we make
haste to physically isolate electronics
whenever a thunderstorm seems likely!
I hope this makes zapping by voltage
spikes induced by nearby lightning
strikes less likely, although now it has
become something we generally do
whenever the boat will be left unattended
or not actively sailed. So it is no hardship
to apply the same philosophy to the
cockpit electronics too. One could also
argue that routinely storing electronics
below when in port perhaps extends its
operating life, or makes its accidental
damage less likely.

SOME DETAILS
For what interest it may be, our Mk.2 and
#3 pivoting arrangements are based on

ABOVE: Mk3 with VHF,
chartplotter and socket for
below-decks VHF remote mike.

RIGHT: Below decks electronics
rack can slew from port to
starboard and slide aft.

OPPOSITE PAGE: Hidden
connections are neater but
being able to physically
disconnect things
maximises the chance of
surviving lightning-induced
voltage spikes.

“ONCE I HAD LEARNED THE HARD WAY NOT


TO HIT IT WITH MY HEAD WHEN DUCKING


AROUND THE WHEEL, I WAS PRETTY HAPPY.”


Since my boat is nearly always at anchor
or on a mooring, I see the ability to easily
dismount and store the electronics below
decks as an advantage.
As a side benefit, the little
chartplotter can be used in the dinghy,
powered from a portable battery, with
its skimmer transducer clamped over
the transom. Rubber boots are available

to seal disconnected plugs, but for
neatness we also use a canvas bag
that gathers the dangling cables and
tightens around the bracket with an
elastic cord.

BELOW DECKS PIVOTING
Our original 1988 crop of marine
electronics: HF, VHF and ham radios,
were in the navigation area below decks.
They were on sliding racks that allowed
the cable connections to be fairly easily

accessed. But, as our cruising continued
and electronics proliferated, there
simply was not space for radar, then GPS,
then chartplotters and finally AIS.
So the radar was initially suspended
from the deckhead above the engine box
and eventually this overhead bracket
system was expanded to accommodate
the rest on a support frame that could
be swung to port to face
the navigation area,
starboard to face a quarter
berth, or aft towards the
companionway.
The frame pivot could
also be slid aft to bring the
displays ~500mm closer to
the helmsman and reachable by someone
sitting on the companionway.
Cockpit displays are better if that is
where the person is, but I still find this a
practical if not very neat system below
decks. The radar and, even at a distance,
the back-up chartplotter/VHF is visible to
the helmsman.
Depending on your boat’s layout
this might be worth considering as an
alternative to near-helm mounting, as
the gear can be easily disconnected
but does not need to be dismounted.

PRACTICAL


ELECTRONICS

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