Question 3.
- State one use each of the following hand tools.
- Stripper
- Diagonal cutter
- Lead sucker
- Screw driver
- State four possible faults that can affect the smooth functioning of a car radio.
- In relation to the repair of a television receiver, state:
- two importance of a service information manual;
- three fault-finding equipment.
Observation
The expected responses were:
(a) Functions of handtools
(i) Stripper – to remove unwanted part of wire/cable insulation.
(ii) Diagonal cutter – to cut connecting wires into required pieces.
– to remove excess wire leads from circuit board.
(iii) Lead sucker – to remove solder from the veroboard/circuit panel/joint
(iv) Screw driver – to fasten/loosen/drive screws
(b) Possible faults that can affect the smooth functioning of a car radio
- Damaged antenna/no antenna
- Damaged speaker wiring
- Blown fuse
- Wiring short circuit
- Aging component
- Fluctuation in power supply/no power supply
- Dry joint
- Faulty tuning stage/loss of frequency signal
- Damaged/leaking capacitor
- Cut/disconnected wire
(c) (i) Importance of service information manual in the repair of a television
receiver
- It contains training/operating information
- It contains component replacement procedure
- It contains repair procedure
- It provides safety guidelines
- It provides circuit/schematic diagram
- It helps in the identification of component parts
(ii) Fault finding equipment in the repair of a television receiver
- Television analyzer
- Cathode ray oscilloscope
- Logic probe
- Multimeter
- Digital frequency counter
- Signal tracer
- Pattern generator
- Tester/transistor tester
Question 3 required candidates to : state the uses of some given handtools; give possible faults in the operation of a car radio; and, show familiarity with procedure for repair of TV receiver. The Chief Examiner reported that majority of the candidates that attempted question 3 did not respond well to the tasks.