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Subject:Re: Re- basic electronics quest
From:Dan Houg
Date:Sun, 28 Jul 1996 17:01:17 CST6CDT

> 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."