Your etrex came w/ a manual, Phillip. It tells you that you can page through the various nav screens to get COG, SOG, etc. all on the same screen. But before you start depending on it, be sure to set it up for marine use. The Etrex came set up for land nav. Go to the setup screen on the menu and tell it you're only interested in two dimensions (this will make it quicker), knots, and degrees (pick a type, but be sure the Etrex and your compass display the same type - either true or magnetic.)
As a warning, the divergence between true and magnetic is not a constant; it varies as you sail away from where you initially brought the compass and GPS into the same readings. That's why most sailors use magnetic, and consult their charts for the divergence, then do the math in their heads. Or ignore it, since most compasses and sailors can't read down to a degree or two, much less fractions of degrees. If you insist in recalibrating your compass to read degrees true, you can do the work right in your slip. Just consult your chart, do the math, and make the setting. No sailing required, and probably more accurate to boot.
You can tell your Etrex where you want to go, and it will tell you what course to follow, and even tell you where you are on that course and your cross-track error, if any. Check out the 'go to' waypoint capabilities, also discussed in your manual. If you lack a manual, you can download one from Garmin for free at http://www8.garmin.com/manuals/eTrex_OwnersManual.pdf
I have three of these; two are backups. I use them as data sources for my laptop, on which I run nav software SeaClear, also a free download (for XP or earlier operating systems) at http://www.sping.com/seaclear/%c2%a0
The charts are free, of course, from NOAA.
Your laptop will eat about 5 amps, assuming you're not playing music or using much audio. If your batteries are up to it, I recommend SeaClear. Otherwise your Etrex can be much more useful than so far you've mentioned. Good luck!
James R. Muri
BUY: My e-Novels at http://blizzardguy.com/venture/
From: palm_atoll <palm_atoll@...
Sent: Thursday, December 25, 2008 4:57:47 PM
Subject: CYOA - Re: Handheld GPS
Thanks so much. Course over ground or ground track in degrees is
what I need. I can then adjust the boat heading to get the desired
course over ground based on true north and all is well. I do like to
steer by compass and just turn on the gps occasionally to check c o g.
I will swing the compasses before I start the passage.
I have a garmin e trex. Does it have the c o g in degrees digitally?
I am kind of technology challenged. So far I have just used the lat
long and time features.
And is it ok on this forum to discuss and recommend a specific
brand of gps. If anyone has any recommendations it would be helpful.
[Non-text portions of this message have been removed]