Hello, Arthur, Thanks for the idea about using opamps to gain the advantages of both types of current control. The opamp is certainly a versatile device for applications like this. I'll look into it further, too.
Incidentally, the analogy with radioastronomy could be pursued further, perhaps. The extraction of useful information from "static" has been incorporated into a comprehensive signal-processing software package developed and supported by the NSF. It's called AIPS, is openly source-coded and freely available under the GNU-type license. It has already being adapted to biomedical imaging aplications. Best regards, Matthew
