SeaTalks about Electronic Communications

Add a new question or Discussion

* - required fields

Please signin first
Maximum 15 words.
Add your question or discussion in a positive and constructive manner and tone. Be as specific and clear as possible. Other students will vote your question or comment up or down depending on its usefulness and clarity. These are always editable.
Posted 2015, Sep 07 20:37
Just looking at the picture. If my depth is 8ft. for example, I would like to see either depth below the keel or 2ft or depth of the water or 8ft. I'm trying to do the math by using the offset in the example to get either reading.
Posted 2015, Sep 29 03:00
What horizontal line is the text referring to? I only see a dotted radial line. Navigation; Boat Velocity; Polar chart
Posted 2016, Mar 16 15:17
Hello: I'm new to this website and I am trying out different courses. I was hoping to find a tutorial on how to properly set an anchor alarm on a chart plotter in this module, but it only shows it as an option. Does anyone know if this sort of think exists in another course module or can direct me to another link on the internet?
Posted 2016, Nov 13 19:02
To be technically accurate as possible which one would be preferable for this section assuming you can measure both?
Posted 2016, Nov 14 12:28
Are these plots typical of a sloop with just a jib for the downwind portions? Would you see much higher speeds in the lower sections with a gennaker or spinnaker? Or even better with a spinnaker well adjusted with a whisker pole?
Posted 2016, Nov 14 23:10
what is a polar table? I don't believe this term has been mentioned in previous sections
Posted 2016, Nov 14 23:44
From a vector analysis how can leeway be always in the direction away from the wind? for example in a boat moving close hauled the slippage can only be directly perpendicular to the track of the boat (or course of the boat ) if leeway were straight down wind this would mean that the boat is slipping both to the stern and sideways and (if you break the downwind leeway vector into the a plane where the vertical axis is defined by the line connecting the bow and stern. If your boat is moving forward then can there be slippage to the stern (which would be necessary for leeway as defined?
Posted 2016, Nov 17 16:53
Looking it up elsewhere it is "Local Apparent Noon"
Posted 2017, Jun 14 10:29
"Now, we are not on the exact meridian, though, so we'll need to use the Arc to Time Conversion Tables (Figure 19) to correct the time for our distance from the meridian. We are in the time zone centered at longitude 60 degrees West. At 65 degrees 16 minutes west longitude, we are 5 degrees 16 minutes of arc to the west..." How can we use the Arc to Time Conversion Tables if we don't know our longitude beforehand?
Posted 2017, Oct 13 14:47
"Your GPS unit measures your exact position relative to the satellites which are exactly stationary with the earth." Not quite: they complete their orbit 2x every days. It would be more accurate to say "Your GPS unit measures your exact position relative to the satellites who's positions above the earth are exactly known and transmitted with the time stamp received by your receiver." (Some) Communication satellites are in geostationary orbit (the ones that require you to point a dish at them), GPS satellites are not: they are a system of 24-32 satellites orbiting on 6 different planes.
1 - 10 of 21 threads