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Jabiru7252

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Everything posted by Jabiru7252

  1. If we were meant to stay on the ground, we'd have roots...
  2. As a radio tech and Ham I shouldn't be, but I am. Confused. You said it does 3mhz to 11Mhz then said it has a super narrow bandwidth. That would be a good antenna to use on a block where the neighbors bitch about towers cause you could keep it below the fence line. Another 'retirement project' I think...
  3. What about a helical similar to the HF helical ants I use on the amateur bands? Although I personally would be worried about RF getting into stuff it shouldn't. Burned out my home burglar alarm due to HF transmissions (100WPEP).
  4. I paid my aircraft registration fees weeks ago but no registration card received. When I enquired, no answer was forthcoming, just sent another copy of the 'paperwork'.
  5. Yea, I have a 10 year old J170C with only 155 hours TTIS. It still has the brand new smell about it. Always hangered, always maintained, no prangs etc. and all the mandatory crap. I'd sell for $55K but nobody's interested. Instead they waste my time with stupid questions.
  6. Nice! I thought a Savannah could land in a small paddock? Can your mate scope one out?
  7. Looks like you need a plane there because I see very few roads!!! Great picture.
  8. I use both a standard logbook and a spreadsheet to keep a record of my flying. Pity they don't agree on hours flown! If I did lose my original logbook I'd be much annoyed as it does have sentimental value.
  9. That plane was at Gawler recently, where recently means some time between yesterday and a year ago as I have zero sense of time.
  10. You probably will not get a good response unless you give us a better idea as to what you are studying and where and what sort of questions you will be asking. Do you want to know a pilots mating habits, eating habits or activities after dark? More information please...
  11. I agree with Bruce. Magazines these days are more advertising, how I long for the days of magazines like 'Electronics Australia' back in the 70s and 80s.
  12. I have flown into Murray Bridge many times as I have two sisters who live there. The strip is good and the folks friendly. Cannibalism has not been practiced for many years now. Most of the locals can read and write and some have jobs.
  13. Just wash the thing thoroughly in WD40 - that will do the job.
  14. Have you had somebody else come and have a listen?
  15. I'm curious - why not put tail into wind and stick full forward when tying down? As for the force on the tie downs - gravity is pulling my plane against the ground at 3139.2N (that's 320kg x 9.81m/s^2). To get my plane off the ground the force on the tie downs would have to be equal to and opposite to gravitational force. (Actually, it would have to exceed gravitational force). Just for the record, gravitational force is the weakest of the four forces. But I guess falling out of the sky knowing that doesn't help one iota. Man, I can rabbit on...
  16. When it comes to software and web pages, never blame yourself when you can't nut stuff out. When I was first taught software development and programming we had the saying "Don't Make Me Think". That meant the user interface had to be intuitive, simple and obvious. These days that doesn't apply. LIke many things these days, cheap and nasty is the norm. Having had my ramble, I do find this forum easy enough to navigate.
  17. The Garmin GPS units I have used in the past would show a 'cloud' of GPS points covering a diameter of maybe 3 metres, even when I was not moving. That I would expect. 2m/sec is only 7.2 kph and I would not expect a consumer quality GPS to work at that speed. Maybe some fudging with software might help. It can get pretty messy when things like 'Kalman' filters etc. are introduced into the works. That stuff makes my brain hurt. Some GPS unit stop recording when the speed is below some minimum value.
  18. I did a course 'engineering aspects of GPS' at work some 15 years ago. No mention of using doppler shift at all. (Not to say methods haven't changed!) It did mention the math, which I have used in my own GPS software. Included are the two functions using the horrid math needed to calculate range and bearing. Yes, with one antenna you need to move before a direction can be determined. The speed is determined by the time taken between the two points. private double CalcBrg(double lat1, double lon1, double lat2, double lon2) { lat1 = lat1 * Math.PI / 180; lat2 = lat2 * Math.PI / 180; double dlon = (lon2 - lon1) * Math.PI / 180; double y = Math.Sin(dlon) * Math.Cos(lat2); double x = Math.Cos(lat1) * Math.Sin(lat2) - Math.Sin(lat1) * Math.Cos(lat2) * Math.Cos(dlon); double hdg = Math.Atan2(y, x) * 180 / Math.PI; return (hdg + 360) % 360; } private double CalculateRange(double lat1, double lon1, double lat2, double lon2) { return 6371 * (Math.Acos(Math.Cos(ToRad(90 - lat1)) * Math.Cos(ToRad(90 - lat2)) + Math.Sin(ToRad(90 - lat1)) * Math.Sin(ToRad(90 - lat2)) * Math.Cos(ToRad(lon1 - lon2)))) * 0.54; // nm } Those familiar with math and programming in C, C++, C# or Java will benefit from looking at the code.
  19. We don't make stuff anymore. It's all off the shelf stuff and most from overseas. Sad, so very sad...
  20. this is an interesting read. We're dicking around with this sort of stuff at work. https://phys.org/news/2018-11-quantum-compass-satellites.html
  21. I had to leave school before year 12 because back then (early 70s) one could only become an apprentice if they were under 18. I think strangling a teacher played a part as well.
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