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 Electronics, Lighting, & Gadgets HRM, GPS, MP3, HID. Whether it's got an acronym or not, here's where you'll find discussions on all sorts of tools, toys and gadgets.

 10-26-07, 08:48 AM #2 ModoVincere Riding Heaven's Highways on the grand tour     Join Date: Aug 2006 Bikes: Posts: 1,675 Mentioned: 1 Post(s) Tagged: 0 Thread(s) Quoted: 0 Post(s) The lumotec light comes with a built in zener diode to regulte voltage/amperage (watts) to help prevent the bulb from getting fried by the dynamo when speeds become excessive. I have a lumotec head light and am using a very cheap (\$11.99 US) dynamo to supply current, and I've seen 30mph with the dynamo in the active position, and the bulb has survived with no issues. By the way...what does RMS stand for? __________________ 1 bronze, 0 silver, 1 gold
 10-26-07, 11:02 AM #3 JSteiner Jack of all (bike) trades Thread Starter   Join Date: Oct 2007 Location: San Jose, CA Bikes: Surly Long Haul Trucker for Touring, Motobecane Immortal Force for road racing, Old Trek 2300 for time trials, Specialized Hardrock for getting over rocks and through mud and snow Posts: 40 Mentioned: 0 Post(s) Tagged: 0 Thread(s) Quoted: 0 Post(s) RMS is Root-Mean-Squared. It's basically a way of measuring the "average" strength of a signal with varying amplitude. I quote "average" because in a sine wave centered around 0V, the average voltage is 0, but the RMS is .707 times the peak value. Technically speaking, it's the square-root of the sum of the squares of the components divided by the time component. Sqrt((a^2+b^2+c^2)/t). Confusing. The magic number is sqrt(2)=.707 for sine and cosine waves. So when the voltage is a sine wave with 8.5 volts peak-to-peak, .707*8.5=6V
10-26-07, 11:21 AM   #4
ModoVincere
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 Originally Posted by JSteiner RMS is Root-Mean-Squared. It's basically a way of measuring the "average" strength of a signal with varying amplitude. I quote "average" because in a sine wave centered around 0V, the average voltage is 0, but the RMS is .707 times the peak value. Technically speaking, it's the square-root of the sum of the squares of the components divided by the time component. Sqrt((a^2+b^2+c^2)/t). Confusing. The magic number is sqrt(2)=.707 for sine and cosine waves. So when the voltage is a sine wave with 8.5 volts peak-to-peak, .707*8.5=6V
Thank you. I would never have gotten that without a good explanation...which you gave.
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