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3-64. If a P-type material is used to construct the
gate of a JFET, what material should be
used to construct the remaining part of the
JFET?
1. N-type
2. P-type
3. Mica type
4. Junction type
3-65. What is the key to FET operation?
1. The control of the effective cross-
sectional area of the channel
2. The control of the effective cross-
sectional area of the gate
3. Both 1 and 2 above
4. The low input impedance compared
with the high output impedance
3-66. When reverse bias is applied to the gate
lead of a JFET, what happens to
(a) source-to-drain resistance of the device
and (b) current flow?
1. (a) Decreases
(b) decreases
2. (a) Decreases
(b) increases
3. (a) Increases
(b) decreases
4. (a) Increases
(b) increases
3-67. What is the "pinch off" voltage of an FET?
1. The voltage required for the FET to
conduct
2. The voltage required to overcome the
FET reverse bias
3. The voltage required to reduce drain
current to zero
4. The voltage required to reduce gate
voltage to zero
Figure 3G.
JFET common source amplifier.
IN ANSWERING QUESTIONS 3-68 AND 3-69,
REFER TO FIGURE 3-G.
3-68. What type of transistor is shown in figure
3-G?
1. N channel JFET
2. P channel JFET
3. NPN/channel JFET
4. PNP/channel JFET
3-69. The circuit shown has which of the
following characteristics?
1. Low impedance, high current gain
2. Low impedance, high voltage gain
3. High impedance, high current gain
4. High impedance, high voltage gain
3-70. The MOSFET has which of the following
advantages over the JFET?
1. Less bias
2. Higher input impedance
3. Higher output impedance
4. All of the above