[volt-nuts] fluke 731b battery pack

[Orin Eman]

On Wed, Aug 3, 2016 at 2:08 PM, David <davidwhess at gmail.com> wrote:

>
> I looked at the schematic and is seems feasible without excessive
> effort.  Either the existing simple series preregulator can be
> modified or replaced allowing it to both charge the battery (through a
> blocking diode) and power the instrument or a completely separate
> power charging circuit can be added in parallel.
>


The existing charging circuit _is_ in parallel with the pre-regulator; they
are separated by CR5 and CR6 and the pre-regulator/battery outputs are
combined by CR8 and CR9.  The only problem with the existing circuit is
with a fresh, strong, fully charged battery pack, charging pulses will leak
past CR8 with only R1/C1 to filter them.