The original poster seeks to understand the uses of capacitors, resistors, and diodes in devices such as laptop computers, MIDI sound systems, and iPods.
Some participants provide insights into the roles of components, while others seek clarification on terms and concepts. There is an ongoing exploration of how these components interact within the context of charging devices and managing signal levels.
Participants express uncertainty about specific terminology and the practical applications of the components in question. The discussion reflects a mix of foundational knowledge and gaps in understanding, particularly regarding the implications of component functions in real-world scenarios.
rock.freak667 said:Diodes convert an AC to a varying DC, which isn't too useful. So capactors are added which helps to convert a varying DC to a more or less steady DC
Delphi51 said:When AC is converted to DC to run electronic devices, there is 60 Hz powerline ripple in the DC which would cause 60 Hz hum in any audio device and all sorts of trouble in a logic circuit. A capacitor from the DC + to DC - will store voltage in the highs and release it in the lows tending to average out the voltage to a steady value, eliminating the hum.
Interference from radio transmissions, lightning, welding, people switch motors on and off will cause high frequency transients on the device. Capacitors are like short circuits to these high freqs, so they are eliminated, too.
mgb_phys said:Perhaps a simpler example - diodes only let electricity flow one way.
How would this be important in say charging an iPod?
Variable resistors change the level of a signal - when would you need to do this on an iPod?
Probably not needed for that, since the charging V will be higher than the V of the batteries. I was thinking of preventing damage to the circuit when operating on batteries, when the batteries have been put in backwards, with reverse polarity. A diode would prevent current from flowing backwards which could damage the circuit. This is a 5 cent solution to what would otherwise be a big problem.So the diode would prevent the electricity from flowing from the ipod to the charger?
Delphi51 said:Probably not needed for that, since the charging V will be higher than the V of the batteries. I was thinking of preventing damage to the circuit when operating on batteries, when the batteries have been put in backwards, with reverse polarity. A diode would prevent current from flowing backwards which could damage the circuit. This is a 5 cent solution to what would otherwise be a big problem.
And the resistors are used in the volume by letting out set amounts of current through?
Yes, a volume control is basically a variable resistor that selects part of the signal - usually potential rather than current.