Rich, AG6K, writes:
>The ESR of flash-caps appears to be higher due to use of thinner plate
>material - which allows the designer to pack in more C - and more Joules
>per unit of volume.
This is of great interest, Rich. Let us suppose that the plates
are ultra thin, but that the insulation is of the standard dimension.
If that be true, *voltage* ceases to be the issue. Instead,
*current* becomes the problem. Does it make any sense to imagine
the following?
Thin plate material is OK in flash service, even to handle
the huge (but only occasional) current flow in a discharge,
because the slow rate of recharge requires tiny current flow,
and there is a long static interval between discharges. Thus,
there is no tendency to overheat.
In filter-cap service, though, the cap is charged and
discharged (albeit only incrementally) all the time,
so some current ingress and egress goes on constantly.
Might this create a heat accumulation problem that would
be absent in flash service?
Just a thought, Rich. Your reaction?
73 de Bob, K0KR
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