Ken Gresham wrote:
>
> Anyway, I would appreciate all opinions as to what all could
> possibly be done before top goes on and how to accomplish these
> things. Examples: Comm antenna? and how to route, Nav antenna?
> how to route, Transponder antenna?
Antenna coax should be routed for shortest lengths, as signal loss per
foot is not linear but logarithmic. Rule #2 is avoid any sharp bends,
like an inch or less in radius. Avionics install manuals generally
caution against bundling various coax together, and bundling coax
within a wire bundle containing noisy, high current 14V feeds - Rule
#3. Although, peek at the innards of typical installs in airplanes,
including factory installations, and you might find they tend to
ignore #3 and usually get away with it.
A given installation may eventually have to bring all wires to the
panel in close proximity, so the way I've done it is wire the coax so
I can move it later if need be, given limited access issues when
everything's all glued up.
A handy way of affixing coax to fiberglass is with nylon,
self-adhesive squares which accept a ty-wrap to secure a wire. Peel
off the protective tape, and affix it with minute-cure, 2-part epoxy
like from Wal-Mart. Many sources for such fasteners, but one is
www.allelectronics.com. Search on Cable Ties. To make good use of
the flat shipping charge, stock up on BNC connectors, coax, affordable
multi-conductor cable, shrink tubing in many colors/sizes, fuses, and
switches. Check out their oddball stuff, like one time for a few $
they had these almost lima-bean sized, rubber case flashlights you
attach to your key ring. A really high-intensity LED with a seemingly
forever battery; you just squeeze the bean to operate. Why such
clever little items tend to show up mostly in pure electronics surplus
houses like allelectronics vs. Wal-Mart for more $ ending in .96 cents
I've never yet figured!
Reg,
Fred F.
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