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Wilbur Hubbard Wilbur Hubbard is offline
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First recorded activity by BoatBanter: Feb 2007
Posts: 2,869
Default Lucaya, Grand Bahama Island to Saint Simons Island GA April 18-19

"Brian Whatcott" wrote in message
...
Responding to abusive, wrong-headed posts from alias-Wilbur is very much
like banging one's head against a wall for fun - but I'll do it any way.

Radar output is the transmit power from the magnetron.
This pulse lasts 1 microsecond or less, and can be repeated 1000 times per
second. 2.2 kW power for say 1 microsecond X 1000 per second gives AVERAGE
power of 2.2 watts - but there is the processor, the display etc., etc so
20 to 30 watts while transmitting is in the ball park.
A coupla amps in fact.

I expect there was SOMETHING correct in alias-Wilbur's post, but I didn't
look at it that closely.



If you aren't transmitting you aren't using radar. Doh! And, if you have
working radar you are REQUIRED by the COLREGS to have it on and operational
at ALL TIMES that you are under way.

RULE 7
RISK OF COLISION

(a) Every vessel shall use all available means appropriate to the
prevailing circumstances and conditions to determine if risk of collision
exists. If there is any doubt such risk shall be deemed to exist.

(b) Proper use shall be made of radar equipment if fitted and
operational, including long-range scanning to obtain early warning of risk
of collision and radar plotting or equivalent systematic observation of
detected objects.

(note: proper use does not mean turning the damned thing off to conserver
your battery power!!!)

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We all know manufacturers fudge their stats to make it look like their
products are not the power hogs they really are. I refuse to believe the
claim that Rube made about their radar set only using 2.1 amps. It's
obviously way understated. Hell, the LCD display alone on my laptop draws
about that much power. The power brick outputs 19 volts DC at 4.5 amps. The
radar set is a computer, too. It has a processor and that antenna spins
inside the dome so it has a motor and motors draw lots of amperage. We all
know that.

The bottom line is my original statement stands. Radar sets for sailboats
draw way too much power to be viable unless you run your motor or a genset
all the friggin' time.

Wilbur Hubbard