On Thu, 2010-12-09 at 20:06 -0800, Kirk Wallace wrote: Some corrections: 74HC04=Hex Inverter, I tried a 2in NOR, but it's all the same. > I blew out the only 74HC (74HC04 NAND) part in my junk box, so I cut my ... snip > I also wired this up: > > +--------- O'Scope > _ _ | > _| |_| | | C1 .01uF > -----------\/\/-----+---||--+ > R1 15k | > V (gnd) > > If T=RC, T=15000x.00001=.15 ?
.01uF = .01 x .000001 = .00000001F .00000001 x 15000 = .00015 > On the scope, I got a shark fin like signal where most of the signal > change occurred by 200ms, should be .2ms = .0002ms > so I guess this confirms the .15 for T above? > I didn't quite understand what I read on Wikipedia -- something like RC > is the value where the signal change is at around 63% of the signal > swing? I suppose I could use this circuit to measure caps with C=T/R > with t...@63% of signal? I'll have to play with this some more. It's confusing enough without goofing up the decimals. -- Kirk Wallace http://www.wallacecompany.com/machine_shop/ http://www.wallacecompany.com/E45/index.html California, USA ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
