GPS Speedometer

Thread starter #1
I'm thinking of purchasing a GPS based boat speed indicator. Any suggestions? Does a cheap GPS work well enough?

Here are two that are clearly out of my price range: $600 for the white one and $340 for the black puck.

-- Ed
I´m using a Garmin GPS Handheld, give you maps, speeds, bearing etc, and it's waterproof. I really like it, mine is an older version but the new ones are USB compatible to downloads your trips. I will not buy an expensive speedometer, a GPS give me more.
I bought a Garmin Forerunner GPS wristwatch:
Garmin Forerunning 310xt

I was always fumbling around with a handheld. I found Forerunner is used by triathletes because it is waterproof. I use it for sailing, sailboat racing (it's my race timer as well), and hiking.

It will upload your tracks automatically to your online training center -- free for use via Garmin. You can view speed, elevation, etc, all for playback online.

Thread starter #5
Thanks Patrick, Vick Roy, and Robert!

Do any of you know if the normal GPS (not sailing) like you are using can read in knots?

@Robert: From the Garmin page, it looks like there are lots of versions of the Forerunner series. Did you consider any of the lower priced wrist GPS's? I'm thinking you are right in that I'd be fumbling around with a handheld; unless there's a way to strap it to my PFD!

Also, Robert, it made me chuckle to think of you using the GPS to measure how far out you are extended while hiking in your Capri. Boy those things are sensitive! :) Just kidding!

Thanks again -- & any other suggestions?

I bought the Garmin 310xt because it was waterproof and looked like it had the features that I wanted at the time. There might be newer more featured GPS wristwatches on the market now. I frequently sail solo, so having the GPS on my wrist is always very convenient. Handheld vs wristwatch vs the hockey puck style, each have their benefit.

My handheld GPS always seemed to be out of arms reach or turned sideways whenever I really wanted to have a look at it. I guess a proper mount would have fixed that problem, but I always let it hand from the lanyard strap.... which ended up being a bad idea when I was sailing a hobie cat last year. It must have gotten caught or hung up on something, because it was gone at some point during a day of sailing.

On the wristwatch, it does run, bike, swim, and other. I use the Other setting for sailboat racing, and have it set for the 5 minute countdown. When I press start, it initiates the 5 minute and starts recording my tracks.

I was not able to find a knots setting, but I've always stuck with mph.

The wristwatch will also sync up with a heartrate monitor, shoe fob, and bicycle cadence monitor... not sure I will ever use any of those features. But, it comes with a little device that looks like a thumbdrive, and sync's the wristwatch to the pc and internet whenever in range -- and when it has updates.

Here are the tracks from my last sailboat race I did: --- I was racing my Catalina 22 that day.

I have since bought another handheld GPS unit, because the wristwatch doesn't do mapping. It will do all the standard heading, distance, speed, etc. I use my handheld at different times, especially for hiking, because it does mapping and topo-maps. The handheld also was ideal for sailing the intercoastal, because of the detailed maps and markers I had on the unit.

Most of them will read knots, mph and/or kph - just find and go to te "units" menu to change. I have several fixed GPS units on my Bertram and the Garmins are always the simplist to use by far and most readable to my poor eyes. All the handhelds I've used eat batteries at an amazing rate, which is a big drawback.


Have you thought about an Iphone? You can get the 3Gs for $49 and there's an App called MotionX GPS (99 cents) Has the option to change from MPH to Kts, a compass, and gives you SOG (speed on the ground) and VMG (velocity made good). Plus you can call for a tow!
I've got Motion X on an iPhone. It is a great program, but will say two things about it. First, it appears to be quite a battery sucker. Second, be careful not to get your phone wet.