From: "oryoki2000" <>
> Walter Knapp's message 10896 in September, 2003 explained how the
> battery meter of the HHB is calibrated for alkaline cells. NiMH
> batteries have a different pattern of discharge than alkalines. So a
> reading of 50% battery remaining on the HHB meter means the NiMH
> cells probably have only 1% of power left. Continuing to discharge
> the NiMH battery to the point of exhaustion is very likely to damage
> the capacity of the battery.
I consider any reading below 90% to be time to change batteries. You
pass the point sometimes given as risking damage at about 60-70%.
As another note on the Portadisc and carrying batteries, I use the
PortaBrace case that's made specifically for it. That has a back pocket
of about 8" x 6" x 1". I use that to carry a spare AA caddy and my field
note cards. But it would probably cart one or two NP1 or similar pac if
needing long powering.
> Under ideal circumstances, the Portadisc or Marantz 670 should record
> up to four hours on a single set of AAs. I'm sure that my
> colleague's rechargeable AA cells have been degraded by over-
> discharging, and no longer offer the full power they did when new.
> So two hours of life is all we can reliably expect from his AA
> battery sets.
I should note that four hours out of the Portadisc will require the most
recently introduced size AA's, the 2200mah. If using lower capacity
batteries you won't get that long. If you need long life, sticking with
older, lower capacity batteries is not a good idea. With the original
1550mah batteries the Portadisc got a bit over 3 hours.
I have several uses for rechargeable AA's with my night recording. So, I
demote lower cap batteries to those and get new ones periodically. Up to
recently I was still dumping the last of my nicads as they died, but I'm
all NIMH now.
If he's flattening the batteries before changing, then he could have
degraded them as well. Not a good way to have long life out of batteries.
Walt
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