Bredhurst Receiving and Transmitting Society

3I Circuit symbols

3i.1 Understand the meaning of the symbols used in Table below:-

Students are not making the effort to learn this information may be considering that it is not necessary for the exam even though it is an exam syllabus topic.

By learning these symbols you will be certainly assured of a simple mark in the exam if a question turns up. So look for the similarity in the symbols.

As a learning aid make up a set of flash cards with the symbol drawn on one side and the text on the other so that you can easily test yourself.

s.p.s.t = single pole single throw. There is only one switch which, makes contact so it is like a normal light switch either on of off.

d.p.s.t = double pole single throw. Here there are two switches that switch separate circuits but at a simultaneously.

This is quite straight forward and you will have to just learn them off by heart. It would be a good idea to print them out and have some one test you.

In the exam you may have a question that shows you a symbol of say a transistor or fet and asks you to identify one or more of the connections. So do not look at these items in isolation of the other parts of the course where explanation is given as to use.