John V. Moore wrote:
>The HHB was a problem because of its huge gluttony
> for battery..at least 3 sets [of 8 cells] per day
This mirrors the experience of my colleague in Venezuela. He keeps
his recorder (Portadisc or Marantz 670) on record/pause as he walks
through the forest so he's ready to capture an unexpected
vocalization. Used in this way, a set of rechargeable NiMH AA cells
lasts about 2 hours.
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.=20
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.=20
So two hours of life is all we can reliably expect from his AA
battery sets.
The inconvenience of carrying multiple sets of AAs, and the
frustrating need to change batteries in the middle of a recording
opportunity led us to switch to an external battery with greater
capacity.
We chose to use a 60 watt lithium-ion battery pack. This battery
powers the Portadisc or Marantz 670 for 20 hours, more than 2 days of
typical use in the field. This battery weighs about 44 ounces. It
can be carried in a belt pouch, or in the bag protecting the recorder.
Since 8 AA cells provide 2 hours of service, 20 hours of recording
would require 80 AA batteries (and 10 changes of battery sleds). 80
AAs weigh about 60 ounces, so the Lithium-Ion battery saves a little
weight on an overnight trek, too.
We ordered our battery packs from www.digitalcamerabattery.com. The
batteries are very expensive, but so far they have survived the dust,
humidity and bumps of field use in the tropics, and have reduced the
inconvenience that a "huge gluttony for batteries" presents. And the
freedom of not needing to constantly check the battery level meter is
great!
--oryoki
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