Interface LPG gas sensor MQ5 with LabVIEW using NI USB 6008 DAQ card

Objective:

• Interface the LPG sensor MQ5 with LabVIEW.
• Acquire the data as an analog input signal.
• Give a hardware indication with blink light and beep sound when gas leakage is detected.
• Draw the front panel like the figure shown below.

Study of diode as a Clipper & clamper Circuit

 Objective:-  Study of the diode as a clipper & clamper. Draw and measure the input and output waveform.

 Required Components: - Resistor 1K -1 No, Diode (1N4007 ) -1No, A.C Voltage, DC Voltage, DSO, Coupling wires, Multi meter

Theory:-

For a clipping circuit at least two components—an ideal diode and resistor are required and sometimes a dc battery is also employed for fixing the clipping level. The diode acts as a closed switch when forward biased and an open switch when reverse biased. Depending on the orientation of the diode, the positive or negative region of the input signal is “clipped” off and accordingly the diode clippers may be positive or negative clippers. Half wave rectifier circuits can also be called the basic clippers. 

Study of Opamp as summing & difference amplifier

The Summing Amplifier

Object:-  Design the circuit diagram. Determine the theoretical output voltage of summing amplifier. Take the practical output voltage reading.

Required Equipment :-  Multimeter, CRO, CDS, Power Supply ±15V  for Opamp

Components required:- Op Amp (Ic741) – 1No  2)Resistors Rin=1k-2nos ,  Rf= 1K

Theory - The Summing Amplifier is a very flexible circuit based upon the standard Inverting Operational Amplifier configuration. As its name suggests, the “summing amplifier” can be used for combining the voltage present on multiple inputs into a single output voltage.

Summing Amplifier Circuit

Study of LDR as Darkness Detector

Objective:- To test a LDR as darkness detector and operating  a transistor as a switch.

Equipments required:-1) power supply 5V, Bread board

Components:-1) LDR, Transistor BC548, LED,resistors-100k, 330Ω.

Theory:-  A light dependent resistor or LDR can be used to detect darkness. The resistance of a LDR depends on the light falling on it. So it has a dark resistance and light resistance. This change in resistance drives a transistor into cutoff and saturation. Here the transistor acts as a switch.

Circuit diagram:-

 

Procedure:-1) measure the LDR resistance in dark and light

                     2) measure the Vce,Vbe,Ic when LDR is in darkness and when in light