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From: sukenick@sci.ccny.cuny.edu (SYG)
Subject: Re: AD conversion
Message-ID: <1993Apr15.174208.1209@sci.ccny.cuny.edu>
Organization: City College of New York - Science Computing Facility
References: <1993Apr13.181720.13214@vax.oxford.ac.uk> <b-clark-130493222951@aragorn24.acns.nwu.edu>
Date: Thu, 15 Apr 1993 17:42:08 GMT
Lines: 33

>> I am working a  data acquisition and analysis program to collect data
>> from insect sensory organs.
>> Another alternative is the use of the sound input port.
>
>Can you really make due with the non-existent dynamic range of an 8-bit
>converter, of probably dubious linearity and monotonicity, and perhaps
>AC-coupled as well?

It would depend on the requirements of the poster's data, for some
purposes 1/256 resolution (with or without calibration curve).


Otherwise the other possibilities would be:

1) get a digital voltameter with serial output & connect to serial
port on mac, collect data with some communications program.

2) Buy an A/D chip from Analog devices, Burr-Brown, etc, connect to
a parallel to serial converter, use serial port for acquisition
(nah. too much soldering and trouble shooting :-)

3) Get a board from National Instruments, Data Translation, Omega,
etal.  The finest solution, but possibly the most costly.



To the original poster:  if the signal is too large, why not
use a voltage divider? Two resistors, cost very cheap...
-- 

					-george
					sukenick@sci.ccny.cuny.edu
					212-650-6028
