22. Between the peak point and the valley point of UJT emitter characteristics we have ___ region.
A. saturation
B. negative resistance
C. cut-off
D. none of the above

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23. A diac is turned on by
A. breakover voltage
B. gate voltage
C. gate current
D. none of the above

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24. The device that exhibits negative resistance region is
A. disc
B. triac
C. transistor
D.UJT

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25. The UJT may be used as
A. an amplifier
B. a sawtooth generator
C. a rectifier
D. none of the above

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26. A diac is simply
A. a single junction device
B. a three junction device
C. a triac without gate terminal
D. none of the above

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27. After peak point, the UJT operates in the ___ region.
A. cut-off
B. saturation
C. negative resistance
D. none of the above

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28. Which of the following is not a characteristic of UJT?
A. intrinsic stand off ratio
B. negative resistance
C. peak-point voltage
D. bilateral conduction

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