SignalPrep
Basic Qualification · B-006 Feedlines and antenna systems · B-006-010-010

Pourquoi utilise-t-on souvent une bobine de charge avec une antenne HF verticale mobile?

  1. APour filtrer le bruit électrique
  2. BPour annuler la réactance capacitive
  3. CPour diminuer les pertes
  4. DPour diminuer le facteur Q

Correct answer: B — Pour annuler la réactance capacitive. Question tirée de la banque officielle d'ISDE.

Why

A short mobile vertical antenna acts like a capacitor because it is too small to be a full wave, creating capacitive reactance that blocks efficient power transfer. The full explanation — and one for every question — is in Pro.

Practise this section

Feedlines and antenna systems is section B-006 of the Basic exam: Getting the signal out: antennas, feedlines, SWR, baluns, matching, and why antenna length depends on frequency.

Drill B-006 — free, no account

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