The circuitry of the seismometer is suitable to directly drive a chart recorder
or a conventional drum recorder. A very useful alternative is to send the
seismic signals to a computerized data logging system. In addition to the
obvious advantage of saving the costs of chart paper and pens, an enormous
amount of data can be saved to disk for later, nearly instantaneous recall.
Additionally, the data can be smoothed, filtered and analyzed in any manner
desired, by using suitable algorithms in the software.
The following is a small (but growing) list of hardware/software packages
that are available at a nominal cost. There are numerous computerized logging
and data analysis packages on the market, costing many hundreds of dollars.
I've restricted this list to systems costing less than about $100, on the
premise that the construction of a homemade seismometer implies that the
builder doesn't have unlimited resources at hand.
For the technically inclined, a 3-channel analog-to-digital converter with
a simple yet flexible software (freeware) package is available
from the Radio-Sky
Publishing Co
website. This system can be built for less than $30. If you can construct
the seismometer preamplifier circuit, you can certainly construct this
little beauty! The A to D converter interfaces directly to your computer's
parallel port.
One of the best values in commercial, off-the-shelf systems is the 2-channel
device offered by DATAQ Instruments.
It is called the DI-151RS Starter Kit, and it contains an
elaborate software package with terrific data analysis capabilities.
The price, for both the hardware and software is just $99. I am usually
skeptical of any commercial package that sounds "too good to be true,"
but this system far exceeded all my expectations. It interfaces to your
computer's serial port. Check their website occasionally for special prices and
discounts that are featured from time to time.
An excellent webpage that contains information on inexpensive hardware and
seismic-specific
software, as well as extensive links to other amateur and professional
seismology resources,
is the Public Seismic Network.
This large group also offers a widespread correspondence forum for the
exchange of ideas and data. Their webpage is elaborate. Plan to spend
a considerable amount time looking through it; you won't be disappointed.
I'll be adding more sites to this page as I become aware of them. Please
let me know, via e-mail, if you learn of a low-priced system to add to
this list.
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