[Rhodes22-list] Toys for Rhodes

[JSusanj at aol.com]

How do the sensors that must be in the water attach?  Are they in through-hulls?  I have always been reluctant to add holes to the bottom of the boat as they are a possible source of leaks but the log would be very useful.


Jeff Susanj
s/v Sweet Medicine
Florissant, MO (temporarily)


In a message dated 5/14/2004 6:19:36 PM Eastern Daylight Time, cen09402 at centurytel.net writes:

> 
> Doug,
> 
> OK, realizing I'm probably going to provoke an argument, here goes...
> 
> 1st of all, complete disclosure.  Dynamic Equilibrium's electronic
> navigation aids consist of an Autohelm ST-50 tridata instrument and a
> Magellan GPS 2000 handheld GPS unit.  The ST-50 tridata combines a
> knotmeter, log, depth sounder, and water temperature sensor into one
> package.  The ST-50 is no longer in production.  The replacement Autohelm
> unit is called the ST-60 tridata & it has essentially the same functions.
> My ST-50 tridata has been in service since 1993 and my GPS 2000 since 1996.
> The ST-50 has been totally bulletproof.  The GPS 2000 got dunked by a wave
> in the cockpit once in 1998.  Despite the waterproof rating, water got
> inside the GPS 2000's case & it failed within 10 minutes of the dunking.
> Magellan repaired the unit under warranty & it has lived inside of ZIPLOC
> plastic bags ever since than.  By today's standards, the GPS 2000 is
> obsolete.  It's slow, with sufficient memory for only 100 waypoints.
> However, it does show one's present position, average speed, plus distance,
> bearing, and ETA to the next waypoint.  Dynamic Equilibrium also has a
> Danforth bulkhead mount ship's compass/inclinometer and an Autohelm ST1000+
> Tillerpilot.
> 
> So what do you envision doing with your Rhodes 22?  If all you plan to do is
> daysail within sight of land; then, you don't need any instruments.  If you
> envision being out of sight of land, sailing to unfamilier ports of call,
> &/or possibly being caught out in fog or at night; then, the above
> complement of functions plus a good set of compass bearing binoculars &
> minus the autopilot are, in my opinion, about the minimum requirement.  You
> need to be able to plot compass, GPS, and dead reckoning (DR), fixes on a
> chart.  A log (total distance) is more useful for plotting a DR fix than a
> knotmeter because it is difficult to maintain a consistent speed while
> sailing.  Unfortunately, the low cost knotmeters like the SR Mariner models
> you cited do not include a log.  You will find the knotmeter will be
> marginally useful for helping you learn how to optimize your sail trimming
> skills, but not for much else.
> 
> The depth sounder is very useful for following a certain bottom contour in
> fog or at night in order to stay a certain distance offshore.  It will also
> provide early warning when you are approaching landfall - often many miles
> before you can see land.  A depth sounder with an anchor alarm is a useful
> feature if you plan on spending any time on the hook.  An anchor alarm will
> sound to wake you up if the depth below the keel changes from more than a
> +/- threshold from a setpoint water depth, presumably because the anchor is
> dragging.  This function is also useful for tacking up a narrow channel.  In
> this case, the alarm will sound to warn you that it's time to come about.
> 
> The water temperature sensor has turned out to be more useful than I would
> have imagined when I 1st got my ST-50 tridata instrument.  Of course it's
> primary function is as a swimming comfort indicator.  But, it's also very
> useful for locating warm currents such as river outflows even miles
> offshore.  It's also quite useful for fishing.
> 
> The 1st instrument you should buy is a good ship's compass & a set of
> compass bearing binoculars.  The 2nd instrument is a handheld GPS unit.
> After that, there are lots of options.  The fishfinders provide a nice
> complement of depth, water temperature, and fish sensing functions.
> 
> You will be disappointed with the SR Mariner KT-5 knotmeter.  Either get an
> instrument with both a knotmeter & a log or don't bother.
> 
> By the way, do you actually know how to plot a fix on a chart using various
> methods and do you understand the rule of the road and other boating safety
> concepts?  If not, then you should spend your money on a basic
> navigation/boating safety course before doing anything else.  The US Power
> Squadron offers a pretty good course.  You should do this before you put the
> boat in the water!
> 
> Roger Pihlaja
> S/V Dynamic Equilibrium
>