James Newtons Massmind wrote:
> E.g. use a frequency to voltage converter to find what frequency the
> signal is, and then filter out that AC component. Send only the
> frequency and the remaining DC signal to the PC. Now, in the PC, use a
> program to reconstruct what the original signal was based on the
> information.

This works in theory if the input signal is a single repeating wave riding
on a slowly varying bias, and the wave shape and phase are not important.  I
haven't been paying attention to this thread that much, so I don't know if
these restrictions are true.

However, in practise it's very difficult to "then filter out that AC
component" given only a voltage representing its amplitude.  This sort of
thing is much better suited to digital techniques.  You could have a DSP
identify the repeating wave, and separate the original signal into the
repeating AC component and a DC component.  I did something similar once in
a system that had to eliminate repeating noise that was only roughly known
ahead of time.  Once you have the amplitude of the repeating signal and the
DC level you send them on to the PC as you suggested.

In other words, your general concept might work, but your algorithm is much
better suited to a DSP than to analog electronics.


*****************************************************************
Embed Inc, embedded system specialists in Littleton Massachusetts
(978) 742-9014, http://www.embedinc.com
-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist