I'm wondering if any list members have familiarity with using PCMCIA
cards to do A/D conversion on a computer, and then write directly to
the computer's hard drive (or an external one)? National Instruments
has several data acquisition cards, and I have been using an NI
E-Series (6062E) PCMCIA card for laptop. It has an aggregate sample
rate of 500 Ks/sec. This allows multi-channel recordings (e.g., for
towed or other hydrophone arrays) or high sample rates for 1 or 2
channels. I've heard others criticize the use of PC's and laptops to
do A/D, because they introduce noise. I have seen this for cheap
(internal) sound cards - but it seems that with high-quality
acquisition cards, as long as your analog signal is well shielded
before A/D conversion, it shouldn't be affected by the computer. Yes?
I have not noticed such issues with the NI DAQ cards, but also haven't
really tested them in a controlled environment.
How about this? I personally like using a laptop because it's quite
versatile and allows you to do other things as well (e.g., run
real-time processing software). I could see the problem if working in
remote or harsh environments though...
Do any list members have any knowledge or comments on this?
-Tom
Thomas Norris
Senior Scientist / Marine Vertebrate Biologist
Marine & Environmental Sciences Div
Science Applications International Corp.
San Diego, CA 92121
[EMAIL PROTECTED]
760-632-6344 (office)
858-361-5656 (mobile)
(858) 826-2735 (fax)
<a href="http://www.saic.com/aquatic-sciences/";
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