*ships are always turning....making knowing which way a
*directional antenna was pointed too complex - it is
*"ever-changing" - only when at anchor would you know your
*bearings...or have a clue as to where "true North" was -
Not necessarily so. Ships, mobile launchers, artillery pieces all have
the ability to maintain almost perfect orientation no matter what their
aspect. In fact, many missile launchers, as well as artillery guns have
a lock out mechanism that only enables a firing when the aspect to
target is in place. You can execute a fire command, but it will not
execute until the aspect is there.
Think of a battleship rolling in high seas. How could they ever hit a
target unless they could maintain aspect to target? We used to be able
to put birds (missiles) in a pickle barrel from a very long distance
away before GPS became the mainstay. These flights had to compensate
for earth rotation, atmospheric striations, elevation differences, and a
host of other factors.
Some ships have very small yagis for VHF/UHF work, but I think it is
more a matter of environmental survival. A vertical can be quickly
withdrawn and seated in a tube or dropped to secure to withstand the
weather or a blast. I remember some of our in ground mounted back up
verticals were in tubes underground and were launched with a small
explosive charge. This was in the event all antennas were downed by a
blast.
With modern GPS systems, I expect it is a piece of cake to know exactly
where you are.
Military memories of an other time.
Jon Hamlet, W4ZW
Casey Key Island, FL
"A little bit of Paradise in the Gulf of Mexico"
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