Question 6A488

A regenerative receiver uses positive feedback to increase sensitivity and selectivity. 1. **Step A (Tune while oscillating):** When a regenerative receiver is oscillating, it acts as a mixer. As you tune across a station, its signal mixes with the receiver's self-oscillation, creating an audible beat note or "whistle." This allows you to easily detect and precisely tune in even very weak signals that would otherwise be inaudible. 2. **Step B (Adjust regeneration for optimal reception):** Once the station is accurately tuned, the regeneration control is slowly backed off until the receiver just stops oscillating (i.e., the "fringe howl" disappears). At this critical point, just below oscillation, the receiver provides maximum gain and selectivity without generating its own interfering squeal, resulting in the clearest and most sensitive reception of AM signals. Therefore, you first use the oscillating condition (A) to locate and tune the station, then back off regeneration (B) for optimal, clear reception.