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Recipe as follows:<br><br>
1 - Connect one side of the switch to ground.<br><br>
2 - Add a pullup resistor to VCC on the other switch contact.
this<br>
gives you a normally high output that goes
to ground when the<br>
button is pushed.<br><br>
3 - Feed this signal via a RC network (series resistor, then cap to
gnd)<br>
to lose the switch-bounce noise.<br><br>
4 - This then goes into a 74LS14 Schmitt trigger invertor.<br><br>
5 - You will now have a nice clean high-going signal out of the
invertor<br>
when you push the button.<br><br>
6 - Feed this to the clock input of a D-Type flip-flop (74LS74) which
has<br>
the /Q output connected back to the D input and
both /SET and /CLR<br>
connected to VCC.<br><br>
7 - Now every time you press the button, the Q output of the flip-flop
will<br>
change state.<br><br>
Voila, one change-over switch from a single push-button. You can
drive<br>
the leds from the Q output through a transistor to take the
current.<br><br>
Serve and enjoy.<br><br>
Jim.<br><br>
At 8-10-03 18:57, you wrote:<br>
<blockquote type=cite class=cite cite><font face="arial" size=2>Quick
question:</font><br>
<br>
<font face="arial" size=2>I need to make a momentary pushbutton switch
turn some LEDs on and off. I.E. you push the button once, they turn on,
you push it again, they turn off. Any ideas?</font><br>
<br>
<font face="arial" size=2>Brian</font><br>
<br>
<font face="arial" size=2>PS - I've been having trouble lately with my
messages coming back from simpits-tech as undeliverable my first try.
Anyone else having this?</font><br>
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