Four Station Quiz
Here we have another Quiz circuit using a number of CMOS ICs. Now the number of contestants can be easily increased even though the present circuit shows only four. It uses a two input Quad AND gate (74HCT08), a four input Dual AND gate (74HCT21), a dual D flip flop (CD4013), and a 555. Truth [...]
Light Alarm (Sun Up Alarm)
This circuit designed to sound a loud alarm at the break of the dawn especially for those wh cannot wake up even with an alarm clock. Circuit can be modified as an intruder alarm or as a security alarm. Needless to say that 1.8 KHz astable multivibrator with 555 is used here again with a [...]
IC555 Interal diagram and description
IC 555 has been one of the most popular ICs since Signetics introduced it in the early 70s. 555 is also called as a TIMER IC. This 8-pin chip is a versatile device suitable for astable, mono-stable and bi-stable operations. It is such a multipurpose device that hobbyists find clever uses of it everyday. It [...]
