4. Electronic fundamentals - Q&A

The most suitable class of amplifier for a high fidelity radio transmitter is

• B.
• C.
• A.

The output of a tachogenerator should be

• exponential.
• linear.
• sinusoidal.

When a hole diffuses from a p-region to the n-region it

• becomes a minority carrier in the n-region.
• lowers the potential barrier.
• raises the potential barrier.

To function, i.e. conduct, a junction diode made of silicon requires a forward bias of at least

• 0.2v
• 1.41v
• 1v

The term "velocity lag" refers to a

• speed error.
• acceleration error.
• position error.

In a diode clamper, if the resistor is removed making the time constant equal to C x r where r is the reverse resistance of the diode, this will ensure a

• long time constant.
• short time constant.
• variable time constant.

What power is required for a desynn indicator system?

• DC.
• AC 400 Hz.
• AC 50 Hz.

A Zener diode is used for

• voltage stabilisation.
• rectification.
• voltage regulation.

In an integrated circuit, the components are mounted

• by metal screws.
• by metal oxide film.
• by means of wires connecting them.

Diodes connected in parallel with their anodes to the inputs and their cathodes joined to a common output would act like

• an NAND gate.
• an AND gate.
• an OR gate.

A Zener diode usually works

• only in reverse bias.
• at variable voltages.
• only in forward bias.

If the reverse bias voltage across a diode is too high

• load current reduces to zero.
• load current increases rapidly.
• load current reverses.

The most suitable class of amplifier for a high fidelity radio transmitter is

• B.
• C.
• A.

A desynn instrument has a positive regular increasing error, you would adjust

• lever length.
• lever angle and lever length.
• lever angle.

In a printed circuit board , the surface resistance testing is

• insulation resistance between adjacent printed conductor.
• the resistance between the two conductors.
• between the board and the conductor.

The common collector amplifier is sometimes called the emitter follower circuit because

• the emitter voltage follows the collector voltage.
• the emitter current follows the collector current.
• the emitter voltage follows the base voltage.

A control surface position feedback signal is

• inversely proportional to surface position.
• proportional to surface position.
• non-linear.

With an NPN transistor electrons leave the

• Base.
• Collector.
• Emitter.

The capacitance of a varactor diode is

• inversely proportional with reverse bias voltage.
• a linear function of applied reverse bias voltage.
• directly related to the forward bias voltage.

When an SCR is switched on it has

• low resistance.
• no change in resistance.
• high resistance.

An atom with 5 electrons in its outer shell is part of

• a C type material.
• a P type material.
• an N type material.

A zener diode is designed to operate

• below its breakdown voltage.
• either above or below its breakdown voltage.
• above its breakdown voltage.

Diodes connected in parallel with their anodes to the inputs and their cathodes joined to a common output would act like

• an NAND gate.
• an AND gate.
• an OR gate.

Damping in a servomechanism is easier to apply if

• the mechanism is light and has high inertia.
• the mechanism is light and has low inertia.
• the mechanism is heavy and has high inertia.

A VLS IC has

• more than 10,000 gates.
• less than 1,000 gates.
• between 1,000 and 10,000 gates.