||The charge carriers of valves are electrons.
||The carriers of the transistors are the electron and holes.
||In a valve the charge carries are provided by heater called hot cathode.
||In a transistor, charge carriers are provided by emitter. No heater or heating elements are required.
||It is not so efficient because large power is wasted in heating.
||It is more efficient than valves since there is no wasting in heating.
||A valve needs high power source of a few hundred volts.
||It needs low power sources of a few volts.
||A valve requires vacuum on its construction.
||It does not require vacuum on its construction.
||A valve does not work instantaneously since time is needed for heating.
||It works instantaneously as the switch is on.
||A valve has large size and more weight due to which it is not suitable to use in different electronic applications.
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||It has small size and light weight due to which it is more suitable to use in the modern electronic applications.
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Difference between Valve and Transistor