> Been watching this one from the sidelines, coward! blunder in here with the of rest of us fools!!! :) > > In digest 1052, Dan said " using a cheapo 12v power supply, that puts out > about 15v unloaded the LED drew about 80ma with a 280 ohm resistor. 1/2 > watt. the resistor " dangit!!! i should've known better with this list--- here's the facts: 80 ma was measured with a good Fluke. i don't know what the pwoer supply was putting out after being hooked up but the open circuit voltage was about 15. i *thought* i was using a 280 ohm resistor but i won't swear to that now... i had a whole pack of them, took what i thought was a 280 but can't remember the color scheme on it. mebbe it was 280, mebbe not :)
> Folks, Ohms law is: don't quote the Law to me officer, i'm innocent!!! ts = amps x ohms. 280 ohms times 0.80 amps = 22.4 >there has to be a measurement error somewhere here. hey, just because i reported 56 mpg with my Toyota once, everybody thinks i can't do ANYTHING right! :) > How accurate is the resistor compared to whatever it may be marked ???? oh, it a radio shack resistor. aren't they the best there is? :) > the critical things here are: 1. Dan may be a turnip. 2. If Dan isn't a turnip, then he may have his feet planted in fertilizer. 3. i still love y'all! can't get away with nothin' :) "Reality is where theory and a good observation meet."
|
Please note - During the past 17 years of operation, several gigabytes of
Vanagon mail messages have been archived. Searching the entire collection
will take up to five minutes to complete. Please be patient!
Return to the archives @ gerry.vanagon.com
The vanagon mailing list archives are copyright (c) 1994-2011, and may not be reproduced without the express written permission of the list administrators. Posting messages to this mailing list grants a license to the mailing list administrators to reproduce the message in a compilation, either printed or electronic. All compilations will be not-for-profit, with any excess proceeds going to the Vanagon mailing list.
Any profits from list compilations go exclusively towards the management and operation of the Vanagon mailing list and vanagon mailing list web site.