One last thing, TTL has a spec of 5V ± 0.5V, so the minimum voltage you should use is 4.5VDC. Don't forget the Schmitt Trigger components. The 10106 is an error on my part, but I'm looking for the right number.

 

not working on bread board again i even tried on bread board with just one switch but still it is not working :S I double check whole connections and matched it with the the circuit and its absolutely correct ,since yesterday i assembled this bread board more than 30 times.

both the circuits are shown below (working on multisim but not on bread board) :S

 

Did you use the components we talked about? The 0.1µF and 10KΩ resistors. You still have not replaced the 7404 with schmitt triggers.

You have 9VDC feeding TTL. If this is real the chips are burned out. TTL has very narrow voltage specs, as I mentioned before. TTL power supply specs are 4.5V to 5.5V. It is one of the classic disadvantages. It also does not interface with CMOS logic well (those 4027s). There is a CMOS family of TTL layouts, such as the 74C04 or 74C14.

You can not mix and match logic as you please, it doesn't work (sometimes you get lucky).

A 40106 is a good CMOS hex inverting schmitt trigger, so is the 4584 and the 74C14 (a CMOS version of the 7414).

A good source for finding chips is Sam Electronics Circuits - Datasheets

You are showing 2.5V on digital logic lines. If it were TTL using 5V for power it would be 3.4V for a logic one and around 0.1V for logic 0. That 3.4V for a logic 1 is why it doesn't work with CMOS well.