The site you pointed me to was very interesting but I use
an older laptop that has no USB connection for the transfer
of data I must use COM1 or LPT1 ports only. I once built my
own 8bit converter that worked flawlessly with timing and
control from the computer using the parallel bidirectional port.
Now I am using the prarie digital model 12-40 which seems
to work ok if I only use the upper 9 bits of resolution.
My sample rates are dictated by the computer tic counter
which runs about 65536/3600 samples per second.
I limit my frequencies to below 9 Hz prior to
conversion. You folks seem to be emailing me about
something I posted ages ago which surprises me.

Sincerely,
gmvoeth
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