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Re: 555 timer...
Original poster: "Barton B. Anderson" <bartb@xxxxxxxxxxxxxxxx>
You just need to invert the output. Lot's of ways to do that. A low
cost solution is:
|---------> = Low Output. When the transistor
is on, this point is low.
pin 3 ----->---RRR--| NPN
of 555 |\
You could always just use an inverter chip such as a CMOS CD40106BE
or equivalent or even a simple opto-coupler to do the same thing. I
have a plethora of chips on hand and usually go that route. But if
not, the above would do the trick with a simple 2N2222A or similar.
PS: If above ascii-art looks ugly, set email to view in a fixed width
font (which I "always" view TCML with).
Tesla list wrote:
Original poster: "Chip Ford" <chipford@xxxxxxxxxxxxxx>
This is kinda off topic but, can someone please help me with
this...I am trying to get a 555 timer rectangle pulse (Basic
Astable) to stay low longer then it is high...Is this possible? I
have achieved near equal (square) but never longer low then it is
high?? Thanks for any help.