lippy 918 #1 June 25, 2002 Howdy, I'm thinking for a little project I'm gonna try and make myself a dytter. Anybody know what I should look for in a pressure transducer, like range, response time, and the like? This is just something I'm gonna mess around with, but I'd like make one that actually works Whuffo you sit on that couch all day? RogerI got nuthin Quote Share this post Link to post Share on other sites
indyz 1 #2 June 25, 2002 You might want to contact Gary Peek. He built a custom barograph to measure fallrates with different suit and flying style combinations. You can find his email in any issue of Parachutist, and you can check out his paper about the barograph here: http://www.pcprg.com/baro.htm My guess: A one-tone Dytter shouldn't be especially hard for somebody with some electronics experience, at least as far as building the hardware goes. Analog pressure sensor to an ADC to a microcontroller. The hardest part would probably be programming the microcontroller to filter out false positives. -- Brian Quote Share this post Link to post Share on other sites
quade 4 #3 June 25, 2002 Is this just a mental exercise or do you actually plan on building and using it? I can't imagine anyone building one from scratch and not spending far more in time, money and effort than just going out and buying one. On the other hand, if you REALLY want to build something useful . . . you could always develop the winky-blinky light that was supposed to go with the Pro-track/pro-dytter that the boys over at L&B just haven't gotten around to making yet.quade - The World's Most Boring Skydiver Quote Share this post Link to post Share on other sites
lippy 918 #4 June 25, 2002 QuoteAnalog pressure sensor to an ADC to a microcontroller. I was thinking sensor to a couple of compatators (one on either side of the window), then logic triggering an oscillator with a speaker on the end. Havn't put too much thought into the circuit though, right now I want to see what kind of sensor output I'll be dealing with. Whuffo you sit on that couch all day? RogerI got nuthin Quote Share this post Link to post Share on other sites
billvon 3,107 #5 June 25, 2002 >I was thinking sensor to a couple of compatators (one on either side >of the window), then logic triggering an oscillator with a speaker on >the end. You will have to temperature compensate the pressure sensor if you use a standard silicon bridge sensor. Also, you will need, at minimum, a low pass filter on the output so moving your head suddenly does not trigger the speaker. You'll also need a way to set it; you can use a pot, but they are notoriously unreliable in the skydiving environment. Quote Share this post Link to post Share on other sites
nws01 0 #6 June 25, 2002 Just cut a hole in you helmet and duct tape a kitchen timer to it. The kind that twists and dings. Check in your log book for the appropriate freefall seconds and use it. When it dings the jump is done and it is time to pull...j/k... Quote Share this post Link to post Share on other sites
jfields 0 #7 June 25, 2002 Nathan, that is totally unreliable. What you need to do is strap a 3000' pole on your ass and pull when it hits the ground. Justin Quote Share this post Link to post Share on other sites
lippy 918 #8 June 25, 2002 I was thinking of using a pot to set it...In what way are they un-reliable? Is it due to temp/pressure changes, or simply wind moving the dial? Whuffo you sit on that couch all day? RogerI got nuthin Quote Share this post Link to post Share on other sites
