HOW TO CONNECT ELECTRONIC COMPONENTS

Here is a quick post on how to connect the basic electronic components correctly. These are cuts from my earlier post. This post is due to a suggestion  from my friend. He thought that a post like this can be used for quick reference and will be helpful to the starters. If you want to knew more about each components check out my other posts.

CONNECTING LED

A LED is a two-terminal electrical component, to identify them

Positive terminal can be identified as the longer leg and shorter leg is the negative terminal.
                         OR
If you look inside the LED you can see two small lead, fat one looks like a flag which is the cathode (negative) and other one looks almost straight which is the anode (positive). The symbol of LED is:-

CONNECTING RESISTOR

A resistor is a two-terminal electrical component

Resistor can be connected either way, that means it have no positive and negative terminal. Both symbols below are used to represent resistor in a circuit diagram. You can use any one of the two symbols:-

CONNECTING CAPACITOR

A capacitor is a two-terminal electrical component.

The ceramic capacitors can be connected either way, that means it have no positive and negative terminal. The symbol used for the ceramic capacitors in a circuit diagram is:-

The electrolytic capacitors have a positive terminal (longer leg) and negative terminal (shorter leg). The symbol used for the electrolytic capacitors in a circuit diagram is:-

CONNECTING LDR

LDR is also a two-terminal electrical which can be connected either way, that means it have no positive and negative terminal. The symbol of LDR is :-

CONNECTING NPN BJT
                                                  
I have marked the  collector (C), base (B) and emitter (E) pins on a real NPN BJT and also on the symbol

CONNECTING PNP BJT

I have marked the  emitter (E), base (B) and collector (C) pins on a real PNP BJT and also on the symbol

CONNECTING 555 TIMER IC

For connecting 555 timer check out this post The 555 timer IC pinout. I have marked each pin on a 555 timer IC and here is the symbol of 555 timer IC:-

LIGHT DEPENDENT RESISTOR (LDR)

A light dependent resistor (LDR) or photoresistor or photocell is a resistor whose resistance decreases with increasing incident light intensity. Below I have shown LDR in different size (small to big).

In other words, LDR is a resistor whose resistance can be adjusted by the amount of light falling on it.

A photoresistor is made of a high resistance semiconductor. If light falling on the device is of high enough frequency, photons absorbed by the semiconductor give bound electrons enough energy to jump into the conduction band. The resulting free electron conduct electricity, thereby lowering resistance.

APPLICATIONS

Photoresistors can be found when we need to control some device with the variation in light.
Photoresistors come in many types. Inexpensive cadmium sulphide cells can be found in many consumer items such as camera light meters, street lights, clock radios, alarm devices, outdoor clocks, solar street lamps and solar road studs, etc.

SYMBOL OF LDR

CONNECTING LDR

LDR is also a two-terminal electrical which can be connected either way, that means it have no positive and negative terminal.