This category covers 14 topics and has 32 questions.

• ADF Polar Diagram
• NDB Polar Diagram
• NDB Range
• LCTR Facts
• NDB Quadrantal Error
• NDB Accuracy
• NDB A1A Modulation
• Commercial Radio Use
• NDB BFO
• NDB Coastal Refraction
• NDB Night Effect
• NDB Radial
• NDB Loop Antenna
• NDB/VOR Variation