Posts: 107
Location: milwaukee | I would do the following:
Fill a 5-gallon bucket with water and set it outside for a day or two, but out of the sun. Beg/borrow/steal a quality outdoor thermometer. Set it near your bucket of water.
Wait for a stable weather period with temps about 80 or so. Check the reading on the thermometer against the nearest accurate weather reporting station, using recent data. You could use a TV station, radio station, Internet, or the NOAA broadcast on your marine radio. Make note of the error, if any.
Now check the temp of the water bucket with your 'calibrated' thermometer. Should be right at air temp if you waited a day or two. Dunk your temp transducer in it and note the error.
You could also make another check down at 32 deg by making an ice bath with 20 lbs. of ice in the 5-gal bucket, topped off with water. Let it sit for a while (30 minutes to an hour, maybe?) and you can be sure it's gonna be 32 deg F, but check with your thermometer. Repeat the transducer test and note the error.
I'd think you'd be able to determine your error to within a degree or so this way.
I'll try this with my Lowrance LMS-337 and report results when done. |
