two NPN transistors
two PNP transistors
one NPN and one PNP transistors
two NPN and two PNP transistors
Open coupling capacitor
Open ON/OFF switch
Very high input signal level
Open bypass capacitor
random checking
checking step by step
trial and error checking
logical checking
signal generator
signal tracer
signal injector
any one of the above stated equipments
Open speaker coupling capacitor
Open output transistor
Open emitter bypass capacitor
All the above stated defects