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1/11/09 New beta release 2.01 - includes real-time calibration.

Read the report on DeWiggler's first season.

The most important mission of an instrument system is correctly reporting wind direction (see Wind direction). If lifts or headers occur every time you tack or gibe, there is a problem with the instrument calibration. DeWiggler is an application and process for determining how much the wind direction changes when tacking and jibing, then recommending adjustments to the instrument system’s calibrations.

DeWiggler comes in two flavors:

  • DeWiggler Pro is used by authorized calibrators and coaches. It produces results on the spot. Pro is not available for sale.
  • DeWiggler Analyst is the 'offline' version. The program is free, but there is a fee for analysis. The 2.00 beta release also includes real-time do it yourself calibration capability to reduce your cycle time to zero.
Both DeWigglers need an Ockam system with RS-232 interface connected to a PC. You will also need OS4, which if only used for DeWiggler, is free.

How DeWiggler Pro works
  • Arrange for a cal professional to come aboard.
  • Calibration tests will be performed and results are immediately entered into your instrument system.
  • The calibrator pays a fee to Ockam for use of Wiggler Pro.

How DeWiggler Analyst works

  1. Download and install DeWiggler Analyst. If you don't already have OS4, you will need to install that first.
  2. Set up an email client (e.g. Outlook) on the same machine so DeWiggler can send results for analysis.
  3. Record a Speed & Heading test, then as many tacks and jibes in as great a wind range as possible.
  4. Email the log files to Ockam for processing.
  5. When the analysis comes back, drag the recommendations file to DeWiggler. Here is a sample report.
  6. Review your cal changes and set the cals into the screws.
  7. Do another set of tests for confirmation, and repeat the process if necessary.
DeWiggler Analyst version 2.00 beta release now includes real-time caibration

DeWiggler Analyst 2.0 beta has the added ability to recommend and adjust calibrations as you sail (i.e. in real-time). This option eliminates the turn-around time inherent in the normal email calibration cycle. If you only have a day before a major race, you might consider using this feature. Read more.

DeWiggler Analyst version 1.53 now includes tack analysis
  • Tacks are analyzed for distance-lost to weather, and 14 other parameters.
  • Tack summary items can be directed to an on-deck graphical display.
In addition to troubleshooting and calibration, DeWiggler Analyst now provides information about your tacking. Use this to find out how to minimize your distance lost to windward in a tack. Read more.


Robert Gordenker (Time Machine, a champion J35 out of Ann Arbor) has been DeWiggled. In his blog, he nicely describes the Care and Feeding of Racing Instruments.

Here is his feedback on DeWiggler

The numbers we are getting now are much more stable than anything we have ever seen before.  We are sailing in a Windward/Leeward regatta this weekend and then in the North American Championships (also W/L) next weekend.  For the first time, I feel that I can really rely on the numbers to help us approach maximum performance.  For this weekend, this is of special importance, since we are the ONLY J/35 out there.  At the NA's we have the best performance measurement yet invented, another well sailed boat right BEHIND us.
Before we hoisted the sails on Wednesday we motored at about 2 knots directly into the wind.  I set up the 'Shear-o-meter' (a line with cassette tape streamers every 6 feet) from the masthead.  I deliberately made the top streamer long so that it would rub against the backstay (Mike's idea).  Using this and the windex I had my 'instrument guy' punch the SET button on the DeWiggler 'Offset' screen and write down the numbers he got for offset.  We gathered 18 numbers and then threw out the lowest 2 and the highest 2, took the average of the remaining 14 numbers and used that as the WindAngleOffset.  The number ended up at -10.009, obviously I can't drill a hole straight (the hole in the wand).
We then hoisted the sails (#3 and full main) and started to work to windward.  The Shear-o-meter had told us that on this night there was little to no wind shear, so I was really interested to see if our TWA would be the same on both boards.  IT WAS within 2 degrees.
Looking at the stripchart of the True Wind Direction, I could not identify the tacking points (no wiggle).  When we turned to set the kite, same thing....  no wiggle and the sailing angles were equal on both sides.  Lot's of wind holes on the run...  Wind was mostly 15-17 knots with 1 minutes periods of 8-10.... the holes always came just as the big wave sets came through, so no surfing  :-(

Kevin Grainger
(Gumption, a J105 out of Rye NY) had his 'wiggle' reduced from 5 degrees to less than 1 after two sailing days.


What's included
Heading only Analysis of your compass deviation only $150
A'la carte One analysis run and report $400
Cal and confirm One primary  and one followup analysis. Reports included. $595
DeWiggler Pro Arrange with Alan for a DeWiggler session negotiated
DeWiggler Real-Time Provides do-it-yourself on-the-spot calibration See the DRT page
Web store link


Current stable revision is 1.53 (9/5/08). If your version is not current, please install the current revision.
DeWiggler Analyst 2 beta release includes Real-time calibration capacity.
If you would like to be added to the DeWiggler distribution list, please send us an email.

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