When a crowbar is used with a power supply the supply

113.) When a crowbar is used with a power
supply, the supply needs to have a fuse or
114.) a. Adequate trigger current b.
Holding current
115.) c. Filtering d.
Current limiting
116.) The diac is a
117.) a. Transistor b.
Unidirectional device
118.) c. Three-layer device d.
Bidirectional device
119.) The triac is equivalent to
120.) a. A four-layer diode b. Two
diacs in parallel
121.) c. A thyristor with a gate lead
d. Two SCRs in parallel
122.) The unijunction transistor acts as a
123.) a. Four-layer diode b. Diac
124.) c. Triac d. Latch
125.) Any thyristor can be turned on with
126.) a. Breakover b.
Forward-bias triggering
127.) c. Low-current drop-out
d. Reverse-bias triggering
128.) A Schockley diode is the same as
129.) a. A four-layer diode b. An
SCR
130.) c. A diac d. A
triac
131.) The trigger voltage of an SCR is closest to
132.)
134.) Any thyristor can be turned of with
135.)
140.) A four-layer diode is sometimes called a
141.)

153.) b. The ohmmeter cannot supply
more than 0.7 V
154.) c. The ohmmeter must supply the
SCR’s reverse breakover
155.) voltage
156.) d. The ohmmeter must supply the
SCR’s holding current
157.) The maximum firing angle with a single RC
phase control circuit is
158.) a. 45° b. 90° c. 180°
d. 360°
159.) A triac is generally considered most
sensitive in
160.) a. Quadrant I b.
Quadrant II
161.) c. Quadrant III d.
Quadrant IV
162.) A PUT is considered programmable by
using
163.) a. External gate resistors
164.) b. Applying preset cathode voltage
levels
165.) c. An external capacitor
166.) d. Doped pn junctions
167.)
168.) Prepared By: Reviewed By:
Approved By:
169.)
170.)
Engr. G. Lagos Engr. Y.