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The return to Cat Maudy…afer 3 months on land

(Captain Pat)

… that I have spent the winter in a dark corner of the basement sucking my thumb while in the fetal position due to this window nightmare. Well… almost. While gas prices were “lower”, we took a road trip out west – a real Lewis and Clarke adventure. This provided a wonderful distraction from the woes of Cat Maudy.

When Captain Jane and I moved back onto the boat a couple of weeks ago I had finished my Cycon winter software projects and so I spent some time de-winterizing the boat and making a list of the all the newly broken stuff and fixing the same.

In addition, I located the Brookhouse NMEA MUX that I bought last fall but haven’t had the time to play with so… let the playing start!

A Brookhouse NMEA MUX is a small plastic enclosure containing the electronics to read upto 4 NMEA 0183 lines (RS422) and an AIS line and combine all that into one data stream which you can connect to your computer via a USB port. What? Yep, navionics talk is gonna smack you in your eyeballs.

Many cruisers outfit their vessels with the following electronic gear: Radar, Chartplotter(s), navigation computers, and last but should have been first instrumentation. They may additionally have email capable SSB communications or satellite communications but I’m not going to address that here.

This is a functional breakdown of what these devices do for the modern cruiser.
o Radar – Visual image of hard objects near your ship.
o Chartplotter – A GPS based mapping device which shows you where the @#$% you are on the planet.
o Navigation Computer – basically the same as a chartplotter but like celery sticks you just can’t have enough of these things.
o Instrumentation – These are usually small bulkhead mounted dedicated devices that display wind direction and speed, water depth, vessel speed thru the water, and water temperature.

Most of Cat Maudy’s navionics were manufactured by Simrad. Measured in window replacement unit dollars ($20,000) it would cost basically 1.5 window replacement units to replace the our navionics. The Simrad instrumentation is the IS15 system which consists of an anemometer, depth sounder, and knot log/temperature sensor all wired to a transceiver which reads the various values and outputs a NMEA 0183 to any device that can read the stream. The IS15 bulkhead mount displays come in 4 or 5 versions each providing a different function. One displays only wind direction and speed. Another displays that plus depth and vessel speed. We have 5 IS15 devices on the boat and they retail for about $300.00 and are a discontinued product so I’m constantly searching EBAY for any good deals on NOS.

Ok so the point is I would like to replace all these little bulkhead displays with one device that will display whatever the pilot needs. Basically, this device will run a version of the CAPN software, display all the instrumentation data and talk to the Autopilot. I’m working on some software to read the stream coming from the Brookhouse MUX and then send that stream to any WIFI enabled computer thru the Windows messaging mechanism. Then write a client which will display that data and run the CAPN.
I’ll report next time on a complete list of the equipment that is we require to do this and how the project is progressing.

And right now if I don’t feed Soxy she is gonna hurt me bad, real bad.

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