Advanced Qualification · A-003 Measurements · A-003-002-005
It gives an indication of the resonant frequency of a circuit How is the output Peak-Envelope Power of a transmitter calculated if an oscilloscope is used to measure the Peak-Envelope Voltage across a dummy resistive load (where PEP = Peak-Envelope Power, PEV = Peak- Envelope Voltage, Vp = peak-voltage, RL = load resistance)?
- APEP = [(0.707 PEV)(0.707 PEV)] / RL
- BPEP = [(Vp)(Vp)] / (RL)
- CPEP = (Vp)(Vp)(RL)
- DPEP = [(1.414 PEV)(1.414 PEV)] / RL
Correct answer: A — PEP = [(0.707 PEV)(0.707 PEV)] / RL. From the official ISED question bank, verified word for word.
Why
The formula uses 0.707 because that number converts a peak voltage into an effective heating value, known as RMS, which is what power calculations require for a resistive load. The full explanation — and one for every question — is in Pro.
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Measurements is section A-003 of the Advanced exam: Measurements: meters, oscilloscopes, counters, signal generators, and what a reading actually tells you.
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