Name that cap...
Gordon JC Pearce
gordon at gjcp.net
Fri Mar 11 09:35:56 CST 2005
Bill Sudbrink wrote:
> You want to look at "Figure #3". I've used several different image
> programs, but I can't get the scribble next to the cap legible. I've looked
> at the data sheet for the chip, but I don't know enough for an obvious value
> to jump out at me. Part of the accompanying text says: "The RC time
> is adjusted to give an output pulse width on pin#1 of the 74LS121 of 5.5
> I assume "ls" is an oddball abbreviation for microsecond?
Well - the spec for the LS121 is pretty well-known. Someone with more
caffeine and inclination than I might well look up the datasheet and
work out what the value ought to be. It looks like it says "270"
overscribbled with "220" to me - what units I don't know. Try 220nF.
If that doesn't work, try 220pF. You'll be in the ballpark with one of
Then, y'see, the phrase is "select on test".
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