Question 6A316

Poor regulation in a power supply means the output voltage changes significantly as the load current varies. Each option listed contributes to this problem: A) **No bleeder resistance:** A bleeder resistor provides a constant minimum load and helps discharge filter capacitors. Without it, the no-load output voltage may be significantly higher than the loaded voltage, leading to a large voltage drop when a load is applied, indicating poor regulation. B) **High resistance filter chokes:** Filter chokes, used to smooth DC, have an inherent DC resistance. A higher resistance choke will cause a larger voltage drop (V = I x R) across it, especially as the load current (I) increases. This increased voltage drop under load directly reduces the output voltage, resulting in poor regulation. C) **Insufficient filter capacity:** Filter capacitors store energy to smooth the pulsating DC from the rectifier. If the capacitance is too low, the capacitors cannot adequately maintain the output voltage between rectifier pulses, especially under varying loads. This causes the output voltage to sag considerably when the load increases, showing poor regulation and increased ripple. Therefore, all these factors independently degrade a power supply's ability to maintain a stable output voltage under varying loads, making "All of the above" the correct answer.