There are 10 questions on the paper. It lasts for 1 hour and 30 minutes.
Think back to some of the work that you have done the revision sheets that I have handed out.
Things that you need to revise.....
Identifying components
Saying which basic components do which job.
ie An led lights up when current passes through it.
ie A diode only allows current to flow in one direction.
Logic circuits - explaining what inputs a system needs.
For example your home central heating controller needs inputs from....
1. The time switch
2. Room temperature sensor
3. Hot water cylinder temperature sensor.
Work on switches - what do they do, how can they be combined?
What happens if you have a couple of push switches in line - in series - with one another?
What happens to the output if they are both on?
What happens to the output if just one or the other is on?
Making printed circuit boards CAD - computer assisted design -
ie what you do with the computer to make the boards.
Checking PCBs for faults etc
Timer circuits
What is a monostable circuit - what does it do?
What in an astable circuit - what does it do?
LEDs , what is a polarised component
Designing cases. Drawing and explaining will all get marks.
hint - answer all the points - check through them.
Fastening PCBs in securely and in an acceptable manner.
Pin numbers on chips.
Digital signals - what is a digital signal?
Which components alter the time delay in a monostable circuit?
Where does an LED and protective resistor connect to a 555 monostable circuit?
Mark to space ratio for an astable circuit.
Decade counter circuits - operated by normal switches - problems?
Schematic circuit diagrams compared to circuit board layouts.
Testing circuits - what/if type questions.
Many of the links will help you with your revsion.
These are scans of the question paper with model answers written in. Look at these and your own.
Other questions and hints etc will appear later.
How did you do on these? What do you need to improve on?
