> >> Purpose of the reservoir cap is to hold charge and deliver it
> >> with more of a force than a weak battery could.

> I am assuming that the tuner runs the LEDs continuously at the tuning
> frequency while it is in use. If that is the case then there is no sense =
in
> using a really large cap. You only need one to hold enough charge for one
> pulse of the LED. You certainly aren't likely to have one big enough to h=
old
> a charge through a whole tuning cycle, which I am guessing will be at lea=
st
> several seconds.

You need about 1000 uF provides ~~ 1V of voltage "droop" per mA per second.

         Vd ~~=3D 1000 . I . t / c

         Vd Volt
         t  seconds
         c uF

For pulsing remove the 1000 and measure t in mS

This V drop is in addition to any  IR resistive drop which will be
instantaneuse.

   Wiring resistance.
   Battery internal resistance.
   Capacitor ESR.

Battery R and wiring R from bat to cap mainly affects cap recharge time.
R cap to load affects instantaneous drop.
ESRcap << Rbat for useful results.

                    R
--=20
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