a capacitor is a storage oriented device . this storage capacity is measured in FARADS. named as such for a guy named FARADAY. unitil the last 10 years , farad capacitors ( in a single package) were a dream
most electrolytic capacitors are measured in MICRO-farads ( example : 100 uF ) or .0001 Farad.
a capacitor is composed of two conductive plates seperated by an insulating medium.
the cause of ur problem is value changes in various 'lytic caps . over time and exposure to high operating temperatures , the electrolytic fluid is lost and the storage capacity drops .
a cap used in power supply fitering could be viewed as a "pour and store" device. pending the outflow rate (current), the bucket can absorb and smooth flutuations of input.
as signal coupling , a cap will block dc but, pass ac. again, changes in the insulator or plates will affect signal
passage....
an increase of "effective series resistance" accompanies the loss of electrolyte , and will restrict signal
passage/ filtering ability .
ESR is the same as putting a resistor in series with your cap. ( think RC time constants--i.e. timing circuits)
adequate explanation
??
qrz