At 01:10 PM 2009-07-02, Rob Danielson wrote:
>I really don't mind carrying a 744T and a 8 lb. mic rig up the
>mountain; its the 45 lb. car battery required for several, 12+ hour
>recordings that hurts.
Hi, Rob,
I have a single Blueshape BMF970 plus the original battery which came
with my SD-722. I have never run the BMF970 down.
http://www.blueshape.net/minidv.asp?lng=3D
I also have the little charger for the battery so I don't have to
charge it on the SD722
http://www.blueshape.net/minidv_chargers.asp?lng=3D
http://www.sounddevices.com/notes/recorders/powering/power-draw/
Says that the 744T uses 12 W when recording, so that would imply
about 4 hours from the BMF970. I _think_ the 722 draws less power.
The manual claims a run time of about 4 hours from the 4800 mAh
supplied battery. Since the BlueShape is 7050 mAh that would imply a
run time of 5.875 hours. Of course, running the battery completely
flat is not a good idea.
I would suspect that with an external 12 V Li-ion battery (4
cells-actually 14.8 V) and three of the BMF970 batteries you'd be
doing real well for much less than 45 pounds. The 12 V external
battery would permit a bridging operation while changing the internal
(rear-mount) battery every four hours. I would think with Li-ion
technology, you could obtain the needed capacity in say a half pound per ho=
ur.
Unattended 12-hour operation might be a little less efficient as I
suspect there are some additional losses when using external power.
If you're using the external 12-V battery for just bridging internal
battery changes you will need to disconnect it because it will always
charge the internal Li-ion battery no matter how it's wired. The
wiring depends on whether the unit charges the internal battery when
the unit is off or on.
In some ways, I lust after a 788T, but the 722 is still rather nice.
>On the other hand, we all look like lazy
>whiners if seen by recordists a mere 20 years ago.
Indeed!
As to the Zoom H2, I am pleased with it using it for church service
recording off our sound board.
All the sermons posted here after March 29th
http://www.trinityaurora.ca/sermons_2009.htm
Have been recorded on the H2 using its line inputs--after the first
week or two, we added a pad and our new Yamaha board has an
individually adjustable output which I intend to use for the H2. See
http://richardhess.com/notes/2009/04/13/zoom-h-2-line-input/ for more detai=
ls.
The June 14th sermon was recorded outdoors with the Zoom near the PA
speaker using its built-in mics. I was away or it would have been the
SD off a mixer, but I was visiting my Dad for the last time which was
much more important. The team came through and got a recording,
however, that was more than merely useable.
Regards,
Richard
Richard L. Hess
Aurora, Ontario, Canada http://www.richardhess.com/
Detailed contact information: http://www.richardhess.com/tape/contact.htm =
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