Hey man, if u r losing ur patience with me. Tell me right away i am simply gonna go to another forum.
Don't get your panties in a twist. I wasn't talking about you. All I meant was, whenever I drop in on the end of a long thread, I don't always have the self-discipline to go back and start reading from the beginning.
The essential principle behind the debouncer that I posted is this:
Charge the cap up to +V through the 1MegΩ and 100Ω resistors while the switch is open (not pressed).
When the switch closes, the cap will discharge to 0 volts almost instantly through the 100Ω resistor and the switch.
When the switch bounce causes it to open a few milliseconds later (or less), the 1Meg prevents the cap from recharging rapidly, so the voltage on the cap stays near 0V until the switch stops bouncing after a few more milliseconds. It then stays at 0V until the switch is released (opens).
The cap then again charges up to +V through the 1Meg resistor, making it ready for the next press.
The Schmitt trigger has positive feedback, so the slow risetime of the cap voltage is squared up, providing the fast edges required by the 4027 clock input. The Schmitt also has hysteresis (provided by the positive feedback), which will clean up any "noise" or severe bounce coming from the switch. Without the hysteresis, any noise on the 4027 clock input which happened to cross the input threshold (≈Vcc/2) more than once could result in the FF beig clocked multiple times, when only one clock transition was actually desired.
I chose conservative values for the resistors. The 100Ω resistor could actually be replaced by a piece of wire (zero ohms), but I like to limit switch current with a low value resistor to protect the switch contacts. The 1Meg resistor could probably have a lower value, allowing the cap voltage to recover faster, so the switch could be cycled faster. Higher values of resistance allow for longer bounce duration, because the cap charges less while the switch is open during the bounce duration.