IF I recall correctly sometime back in the late eighties there was an
article in the hints and kinks section of QST regarding float charging
deep cycle batteries with a power supply and building circuitry to
monitor said system. Any circuit which you could build for this
purpose could be modded for audio output.
ONe thing we use with large capacity gel cells is a float charge
circuit using a garden variety 12 vdc supply. PUt an automotive lamp
in one lead going from the supply to the battery. wHen the battery is
drawing from the power supply the light bulb will light. same could be
done with a buzzer, but I'd think for float charging for emergency
backup power you'd be able to tell when the system was drawing from
the ps instead of the battery by just feeling the lamp. IF it is a
bit warm you know you've been drawing from the supply recently.
73 de nf5b
Richard Webb
Electric Spider Productions
"They that can give up essential liberty to obtain a little temporary
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--- Benjamin Franklin, NOvember 1755 from the
Historical review of Pennsylvania
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