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#61
posted to rec.boats
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A question about radio, sound, "wave length" etc.
"Jim" wrote in message ... "Calif Bill" wrote in message ... wrote in message ... On Thu, 17 Jan 2008 07:24:22 -0800, "Calif Bill" wrote: wrote in message m... On Wed, 16 Jan 2008 21:41:45 -0800, "CalifBill" wrote: wrote in message news:111to39qmnvmde3smd65enr2jkrfk5plih@4ax. com... On Wed, 16 Jan 2008 13:23:20 -0800, "Calif Bill" wrote: Actually is 180 degrees for a peak to peak on a sign wave. But for frequency, it is point to same point on the next wave. You could measure it anywhere on the wave. But Positive peak to Positive peak or Negative peak to Negative Peak or + or - zero crossing all work. Frequency = 1/ time. Wave length = speed of wave / frequency. This will work for sound at about 1126 ft/ second or 300 m/s for radio. What's the matter Bill? Didn't the website you Googled know how to spell sine? Bwhahahahahahaha! Me bad. Especially for misspelling sine. I know all that stuff. My degree is in Electronic engineering. As well as the fact I worked on repairing Radar and Instrument landing systems and nav aids in the Air force. As well as part of my patent includes Sine Square + Cosine Square = 1. If I had googled it, I would have spelt Sine correctly. Harry... Dat you? Nope, I actually did work on the stuff. I have part of a patent on flaw scanning disk drives where part of the circuitry depends on Sine Square + Cosine Square = 1. Interesting part of a flaw in the media, is if it is under the head, you will get reduced amplitude, but if off to the side, you will get a phase shift. Was always hard to detect the flaws off to the side. So if you compare the signal coming off the disk if it is written so it will be a sine wave, and compare the signal + and - 45 degrees and run it through a adder circuit and the output will be 1 until a phase shift and the output signal will decrease and you can detect defects off the center line of the tract. I was just teasing you, Bill. And it is pretty kool that one can expound on a patent concerning disk drives on a boating newsgroup. ;- This is a boating newsgroup? Says do on the label. |
#62
posted to rec.boats
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A question about radio, sound, "wave length" etc.
On Thu, 17 Jan 2008 11:06:27 -0500, "Jim"
wrote: This is a boating newsgroup? Dammit - beat me to it again. :) |
#63
posted to rec.boats
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A question about radio, sound, "wave length" etc.
Wayne.B wrote:
On Wed, 16 Jan 2008 10:42:32 -0500, "Jim" wrote: I know how to measure amplitude or time with a scope. I just can't figure out how to measure distance. You don't measure distance on the scope, it measures time. Given the speed of the wave, typically 300,000,000 meters/sec, it is easy to calculate distance, e.g., a 1 microsecond wave equals 300 meters wavelength. True, except when the dielectric constant (relative permittivity) of the medium is higher than free space, then the wavelength is reduced by 1/sqrt(Er). Common coax cable dielectrics usually have an Er ~ 2.2 and most PC board material is about 4.4 or so. |
#64
posted to rec.boats
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A question about radio, sound, "wave length" etc.
CalifBill wrote:
If I had googled it, I would have spelt Sine correctly. And maybe been closer to the actual speed of light instead of being off by 6 orders or magnitude. c = 3e8 m/s |
#65
posted to rec.boats
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A question about radio, sound, "wave length" etc.
CalifBill wrote:
"Jim" wrote in message ... 360 degrees= 1 cycle is the description I was looking for. Quit trying to confuse me with facts. Check tonights Tampa news videos. Actually may not be 360 degrees. What if it is a square wave? Then it is composed of the fundamental and odd harmonics. 360 degrees is still one cycle of the fundamental. |
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