ACMA Standard Theory Exam study guide
ACMA Standard Theory Exam · Work through your exam, one topic at a time.
The ACMA Standard Theory exam is the written knowledge assessment that sits behind Australia's Amateur Standard Licence. It is aimed at people who want to operate an amateur station with access to the full range of amateur bands and modes, rather than the restricted privileges of the Foundation licence. The ACMA Standard Theory Exam study guide has 8 sections and about 2,313 words.
01Electrical and Electronic Fundamentals
Every question in this domain reduces to charge, current, voltage, resistance and power. Current (I) is the rate of charge flow in amperes; voltage (V) is energy per unit charge; resistance (R) opposes current and dissipates energy as heat.
320 words, about 2 min02Circuit Theory and Components
Resistors combine simply: series R = R1 + R2 + …, parallel 1/R = 1/R1 + 1/R2 + …, and two in parallel give the product over the sum. Parallel combinations are always smaller than the smallest branch.
315 words, about 2 min03Radio Receivers and Transmitters
The superheterodyne receiver converts incoming signals to a fixed intermediate frequency (IF) using a local oscillator and mixer, then filters and amplifies at the IF before demodulation. Selectivity is set mainly by IF filters; sensitivity by front-end noise figure and gain.
302 words, about 2 min04Antennas, Feedlines and Transmission Lines
A half-wave dipole is approximately 143/f metres total length (f in MHz), or 468/f feet; it presents about 73 Ω at resonance in free space. Antenna gain is referenced to a dipole (dBd) or an isotropic radiator (dBi), with dBi = dBd + 2.15.
276 words, about 1 min05Radio Wave Propagation
Ground wave follows the Earth's surface and supports MF and lower HF over limited distances. Skywave relies on refraction by the ionosphere: the D layer absorbs HF by day, the E layer supports short skip, and the F layers (F1 and F2) support long-distance communication, especially around the solar maximum.
287 words, about 1 min06Measurements and Test Equipment
A multimeter measures DC and AC voltage, current and resistance; true-RMS meters correctly read non-sinusoidal waveforms, while average-reading meters are calibrated for sine waves and misread others. An oscilloscope shows waveform shape, amplitude and timing, but probe capacitance and 10× attenuation load the circuit.
287 words, about 1 min07Electromagnetic Compatibility and Interference
Interference travels by conduction (mains leads, cables) or radiation (fields). Common sources include switch-mode supplies, arcing contacts, digital electronics, and a transmitter's own harmonics and spurious products.
260 words, about 1 min08Operating Safety and Good Practice
RF energy heats body tissue; never look into an open waveguide or stand in front of a directional antenna. Exposure limits vary with frequency and are averaged over time, so calculate power density S = P/(4πr²) for a simple isotropic source and apply a safety factor for gain and near-field effects.
266 words, about 1 min