Rich Peet wrote:
> There are many recorders entering the market but there still are no
> good inexpensive 24 bit affordable "frog loggers". This is a device
> that can be programed for "time on", "time off" multiple custom times
> per week. This would allow us to place recording units in the field
> to capture sounds and return to pick up the captured sounds.
Hi Rich,
I'm afraid that there is nobody out there who would be able to
manufacture such an inexpensive unit without declaring bankruptcy
sooner or later.
However, there are already reasonable solutions to accomplish a
long-term monitoring in the field. One flexible option would be to use
an old second-hand laptop (which could be up to about 8 years old), an
USB audio interface and a suited recording software
(http://www.avisoft.com/recorder.htm). The advantage of such a
computer-based system is that it can be also configured as a
sound-activated recording system.
Some laptopts provide an "RTC Alarm" BIOS option that allows to boot
the computer at a certain time each day. The RECORDER software could
then shut-down the computer at a later time.
If the laptop does not support an RTC alarm option, one could use a
separate software tool such as "Auto PowerOn & ShutDown"
(http://www.lifsoft.com).
The most delicate problem to solve is probably the power supply. I
would recommend cost-effective sealed lead-acid batteries such as
http://www.mdsbattery.com/shop/productprofile.asp?ProductGroupID=3D1066.
Unfortunately, the DC supply voltage of most laptop computers is
different from the standard battery voltages of 6 or 12V.
Nevertheless, it would be possible to adjust be required voltage by
combining several batteries and inserting a few rectifiers (1N5400) to
accomplish the required voltage drop (each diode will provide a
voltage drop of about 0.7 V).
Regards,
Raimund
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