I was tidying up in my basement today, near my collection of windsurfing gear (It's like an art collection at the moment.. good for nothing except looking at occasionally) when a mash up of thoughts from the forum occurred to me...
Partly sparked off from Mr. No One's hanggliding thread, and partly from my experiences flying paragliders...
Do any GPS units come with a 'vario' equivalent? The altimeter vario is a device which emits a series of beeps at different frequencies to indicate lift or sink to the pilot (whether they're going up or down, and at what rate). It means that the pilot can adjust what they are doing in order improve their altitude without needing to look at their display.
It seems to me that it would be a good thing to have in a windsurfing GPS as an instant feedback on your trim and technique rather than waiting until the end of the NM to see how you did?
Maybe it's a thought that's already been had, and I just haven't noticed it anywhere?
A much better idea than trying to read the display at speed!!!!
I'd like one of those fighter pilot helmets with the display superimposed on my visor, but I guess that's a long way off for a unit that costs $300
But beeps should be doable without increasing the price very much. Maybe somebody should have a word with Tom?
Tom has been very keen on the idea of the sound feedback idea for a while now. It is in his 'to do' basket for sure. I was trying to push the idea of a HUD (Heads Up Display) on a visor but they all say that is too hard.
I am not too keen in the idea of sound feedback unless it is a voice telling me the speed in knots.
Variable frequency or pitch does not sound 
too good to me. How does one know what pitch or sound is what speed?
Don't think you'd get an actual speed from it, but it would let you know when you are accelerating and decelerating.
Might not be all that much help to somebody as advanced as you, but to us newbies at this game it could help with learning the physical trim of board and sail.
Speed sensation can be deceptive, what feels fater sometimes isn't.
The end of run speed can vary so much by wind strength, it's hard to know what difference subtle changes in trim are making.
But with a whistle to say that's faster/slower the learning process would be quicker.
You could maybe center the whistle frequency around the speed genie trigger point or something like that, middle C (1khz or is it 400hz) could be you're set point. If you have a musical ear, you'd have a rough idea.
Variable frequency or pitch does not sound too good to me. How does one know what pitch or sound is what speed?
The Navi has an overspeed beep. It keeps beeping if you stay over the set speed. If you set it in km/h you can have it at 70 or 80 or 90 (for Chris etc) . The knot divisions are 30 40 50 etc. For the helmet guys it is very audible. Smaller divisions would be nice. Then it could be set at the speed you want to beat that day. On a run you would know how your 250 or 500m speed went by how long the beep lasted and it would stop whenever you dropped below the target speed. It should be a simple software mod as it already has 10kn/10km/h divisions...just needs to be altered to allow 1kn/1km/h divisions.
Using a single pitch to indicate speed would be OK for the very few musicians with "perfect pitch". But most of us, if we can hum a tune, have a good sense of relative pitch so using a method of alternating pitches should be a very good indicator. Every half second the pitch could alternate between a fixed reference pitch to another half second of speed based pitch.
So for instance between 30 and 35 knots you'd get say half a second of reference 220 hz ( = 30 knots) followed by half a second of an even division of 220 - 440 of the speed pitch. At 35 knots the speed pitch would hit 440 hz. (whistle the first bar of Waltzing Matilda - that's 34.99 knots) Between 35 knots and 40 knots the reference pitch could jump to say 440 hz with an even division of the speed pitch for the next 5 knots to 880hz at 40 knots. At 40 knots the reference pitch would change to 880 hz. etc.
the idea of looking at your gps while sailing i find difficult to do as sailing in any sort of chop requires for me,full concentration.perfect flat water would be a different story.
the idea of variable beeps sounds interesting but i am not sure how you would go trying to hear over the general noises associated with sailing.
in my ute i have reversing sensors that beep slowly when in reverse and gradually speed up as i reverse closer to an object (usually the kids bikes) when the car is 150mm from hitting something then the beep is continuous.
this type of indicator sound would probably be a decent enhancement to the gps.
you could configure when the beep kicks in say 30 knots for a steady beep,then a more frequent beep every 5 knots untill your pre configured max (or desired pb!) is achieved.
Have a look at this vid - the beeping you can hear is an altimeter vario. The same thing would work using speed change instead of altitude change..
I readily admit there are times when I am waaaay too 'on the ragged edge' to even try to glance at my GPS but in those runs I can be pretty confident it's a good speed anyhow, and I only have to be patient for another 10-15 seconds and I can stop and look at my top speed and 10 sec max as much and for as long as I want.
