🚀 go-pugleaf

Based on the stated requirements, I would suggest that you consider the
use of an Atari 800XL, at a cost of around $200 including monitor, rather than an ST.  I think it could do all of
the data collection and comparison
tasks you mention.  To pursue this issue in more detail, and to avoid annoying atari-16 types, you should put your question out on the info-atari8 net.  

On the 800XL, the two joystick ports are a general-purpose PIA input/output with
four bits of the 8-bit PIA on each connector.  You could connect a simple interface there to multiplex between the different devices.

The 800XL also has a CPU bus connector on the back, so you can build more ambitious interfaces such as DMA ports to connect there.

The ST family has a DMA port but no direct CPU bus connection available.
Certainly you could use either a 520ST or 1040ST to do your task, but it would
seem like overkill.  However, if you want to include high-resolution graphics
displays of your measurement results, or do other calculations that require a lot
of computing power, then the ST processors make a good deal of sense.

If you already have a TV set or composite monitor available, an 800XL can be obtained for about $70, which is a very inexpensive way to get a laboratory computer.

The 800XL is in fact very much in the class of computers used in the 60s and early 70s as lab systems, e.g. the PDP-8!  In fact, with its 65K of memory, it is comparable to a very big PDP-8 system!

				-John Sangster
				jhs at mitre-bedford.arpa