what is delta F?

Design  a +40 volt dc  power supply for your sound system.  Your sound system requires  a 400 watt capability.     The power supply is energized from a three-wire 110 Vrms  60 Hz power line that meets the National Electric Code (NEC).  The system  block diagram and design specifications  are given below.    Input is a 110 Vrms60 Hz. Output voltage is 40 volts, unregulated. Maximum allowable ripple is 2% Use a full-wave bridge rectifier. Use a transformer Assume diodes with VF= 0.7  volts   Your design should include: Ø Well-labeled circuit diagram of what goes in the “Your Design” box.  There should be enough detail such that someone could build an operational  prototype.  Polarities of key components are important Ø Key design equations and supporting calculations.  Show your work! Ø Component specifications including: (a)            Transformer-turns ratio (b)           Effective value of the audio system load resistor (speaker impedance)  and load current for a 400 watt, 40 volt…

I'm designing a mixer in Qucs. What does input frequency range and input voltage swing mean? Is it the AC voltage source's frequency and peak voltage?