Amateur Extra: LC Current at Resonance

Transmitter tank inductor

This week’s Amateur Extra question is from sub-element 5 (Electrical Principles) group A (characteristics of resonant circuits) [E5A06] What is the magnitude of the circulating current within the components of a parallel LC circuit at resonance? A. It is at a minimum B. It is at a maximum C. It equals 1 divided by the …

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Amateur Extra: What is a Parametric Amplifier?

Variable Capacitor

Today’s exam question comes from the Amateur Extra exam, Sub-element 7 (Practical Circuits) and Section B, (Amplifiers)…  [E7B20] What is a parametric amplifier? A. A type of bipolar operational amplifier with excellent linearity derived from use of very high voltage on the collector B. A low-noise VHF or UHF amplifier relying on varying reactance for …

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Amateur Extra: Identifying in a Pileup

From the realm of “Good Operating Practice” we get our question of the week from the Amateur Extra exam. [E2C11] How should you generally identify your station when attempting to contact a DX station working a pileup or in a contest? A. Send your full call sign once or twice B. Send only the last …

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Amateur Extra: Non-linear Phase Response

Which of these modes is most affected by non-linear phase response in a receiver IF filter? [E7C14] A. Meteor Scatter B. Single-Sideband voice C. Digital D. Video The answer is C. Digital.  Why? Well, for one, the question is pretty vague.  If you’re using a Frequency Shift Keying (FSK) digital signal you probably won’t have …

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