hi,
i am doing a project,in which SR latch is needed.
i used cross connected nor gate.(actually and gate with not gate...not having nor gate)i am using ic7404 and 7432.
but still not getting output...
is there problem with propagation delay?
please help........

 

I do not see your schematic of your circuit.
I do not see a photo of how you have it connected.

There are many variants of the 74xx series. Are you actually using 7404, or is it 74HC04, 74LS04, or something else? Give the entire part numbers of the actual components that you are using.

 

Urgent or not, your question begs for details, details, and still more details. This is also why pictures and schematics are asked for.

You mentioned IC's. Are they good? do you have a test circuit to verify IC operation? Do you have test equipment other than DVM? O-scope? Logic probe?

Good help will require a GOOD description of circuit and all the details.

 

i attached my circuit .

 

That is partly correct. It would be simpler if you selected a 7402, which is a NOR gate.

No pin numbers are given, plus the inputs are floating. The R-S latch only works if one input is HIGH while the other is LOW.

 

You must use pull-down resistors (somewhere between 330 Ohms and 10k Ohms depending upon the full part number) on the S and R inputs to keep them low by default.

When you want to S or R the flip-flop, you can switch the desired functions' input to Vcc.

The circuit will be in an unpredictable state when first powered up.