Advanced Qualification · A-003 Measurements · A-003-004-006
L'horloge d'un fréquencemètre numérique utilise ordinairement :
- Aun oscillateur Hartley
- Bun diapason mécanique
- Cun multivibrateur astable
- Dun oscillateur à cristal
Correct answer: D — un oscillateur à cristal. Question tirée de la banque officielle d'ISDE.
Why
A frequency counter needs a timing source that stays extremely steady to count radio waves accurately, and a crystal oscillator uses a tiny piece of quartz that vibrates at a precise, unchanging rate when electricity hits it. The full explanation — and one for every question — is in Pro.
Practise this section
Measurements is section A-003 of the Advanced exam: Measurements: meters, oscilloscopes, counters, signal generators, and what a reading actually tells you.
Drill A-003 — free, no account