Amateur Extra E6E: MMICs and component packages
These are the 12 official questions in group E6E of the 2024–2028 Amateur Extra question pool, with the correct answer marked and a plain-English explanation of why it's right. The real exam asks one question from this group.
- E6E01Question 1
Why is gallium arsenide (GaAs) useful for semiconductor devices operating at UHF and higher frequencies?
- AHigher noise figures
- BHigher electron mobility Correct
- CLower junction voltage drop
- DLower transconductance
Why: GaAs has higher electron mobility, so it works at UHF and up.
- E6E02Question 2
Which of the following device packages is a through-hole type?
- ADIP Correct
- BPLCC
- CBGA
- DSOT
Why: DIP is a through-hole package.
- E6E03Question 3
Which of the following materials supports the highest frequency of operation when used in MMICs?
- ASilicon
- BSilicon nitride
- CSilicon dioxide
- DGallium nitride Correct
Why: Gallium nitride supports the highest frequencies in MMICs.
- E6E04Question 4
Which is the most common input and output impedance of MMICs?
- A50 ohms Correct
- B300 ohms
- C450 ohms
- D75 ohms
Why: MMICs usually have 50 Ω input and output impedance.
- E6E05Question 5
Which of the following noise figure values is typical of a low-noise UHF preamplifier?
- A0.5 dB Correct
- B-10 dB
- C44 dBm
- D-20 dBm
Why: A low-noise UHF preamp typically has about a 0.5 dB noise figure.
- E6E06Question 6
What characteristics of MMICs make them a popular choice for VHF through microwave circuits?
- AThe ability to retrieve information from a single signal, even in the presence of other strong signals
- BExtremely high Q factor and high stability over a wide temperature range
- CNearly infinite gain, very high input impedance, and very low output impedance
- DControlled gain, low noise figure, and constant input and output impedance over the specified frequency range Correct
Why: MMICs offer controlled gain, low noise figure and steady impedance across their range.
- E6E07Question 7
What type of transmission line is often used for connections to MMICs?
- AMiniature coax
- BCircular waveguide
- CParallel wire
- DMicrostrip Correct
Why: MMICs usually connect with microstrip lines.
- E6E08Question 8
How is power supplied to the most common type of MMIC?
- AThrough a capacitor and RF choke connected to the amplifier input lead
- BMMICs require no operating bias
- CThrough a resistor and/or RF choke connected to the amplifier output lead Correct
- DDirectly to the bias voltage (Vcc) lead
Why: Power is fed through a resistor and/or RF choke on the output lead.
- E6E09Question 9
Which of the following component package types have the least parasitic effects at frequencies above the HF range?
- ATO-220
- BAxial lead
- CRadial lead
- DSurface mount Correct
Why: Surface-mount parts have the fewest parasitics above HF.
- E6E10Question 10
What advantage does surface-mount technology offer at RF compared to using through-hole components?
- ASmaller circuit area
- BShorter circuit board traces
- CComponents have less parasitic inductance and capacitance
- DAll these choices are correct Correct
Why: Surface mount has several RF advantages. All the choices are correct.
- E6E11Question 11
What is a characteristic of DIP packaging used for integrated circuits?
- AExtremely low stray capacitance (dielectrically isolated package)
- BExtremely high resistance between pins (doubly insulated package)
- CTwo chips in each package (dual in package)
- DTwo rows of connecting pins on opposite sides of package (dual in-line package) Correct
Why: A DIP has two rows of pins on opposite sides.
- E6E12Question 12
Why are DIP through-hole package ICs not typically used at UHF and higher frequencies?
- AExcessive dielectric loss
- BEpoxy coating is conductive above 300 MHz
- CExcessive lead length Correct
- DUnsuitable for combining analog and digital signals
Why: DIP leads are too long for UHF and higher.