"it's true!" wrote in message
...
Ahoy, I'm considering one of two budget radars for my portly 23'
sailboat. I can support it with a 220ah battery setup, one 70w solar
panel and a 12hp diesel. (30 yr old Yanmar, I don't know the amp
output).

Probably 35 amps for your alternator.

The Furuno 1621 states 36w (3amps) for operation and 8w (.6amps)
standby. Not sure what standby is. About $1200usd
Anyone have figures for the JRC MkII? Anyone have real world figures,
experience or best guesses? About $900.

According to the JRC website the 1500Mk2 and 1000Mk2 both use 30 watts. I
assume that is during full operation.
They don't mention standby.

I have some questions as I have never owned a radar.
1)
Do either of these have some kind of alarm that will buzz if an
obstruction appears within x distance of my boat? There is something
called watchman mode on the Furuno but no specifics are given.

They should both incorporate an adjustable "guard zone" although the JRC
site does not mention this in the specs.
If an object comes within the distance you have set up for gaurd zone the
radar will sound a buzzer. I think all the diplay units have a built-in
buzzer and you have the option of adding an external speaker.

The "watchman" mode is likely to be a timed off-on mode whereby the unit is
"asleep" most of the time but wakes up at a set interval, scans for a set
time period and then goes back to sleep. During the scan an alarm will
sound if something enters the guard zone. JRC calls this "timed
transmission mode". Saves much power.

2)
Is there another dedicated device which will draw less power and be
less complicated that might serve as an alarm for approaching tankers
less than 5 miles away for example?

There used to be a device called the Card radar detector. It had a
compass-like display on which is showed you where the radar emitting object
was located. It also sounded an alarm when radar was detected. I don't
see it when I do a Google search so it may be out of production. In any
case I think it cost almost as much as one of the radars you are
considering.

I guess my 25 yr old Passport radar detector won't work for this?
I got caught in dense fog last summer so I definitely want the radar
but I'm also interested in a separate device if the radar sucks too
much battery.

I think car type radar detectors are quite directional ? You might have to
do a periodic 360 degree scan to detect ships. Take it down to a port where
ships are coming in with operating radars and see what it does.

Radar would be much more useful though.

Thanks and smooth sailing.

And to you. Try to stay warm in that fog.