On Tue, Mar 9, 2010 at 11:10 PM, M. Adam Davis wrote: > My biggest concerns are: > > =A0 =A0* Obtaining the speed necessary to be reasonably useful without > requiring a lot of components > =A0 =A0* Synchronizing multiple probes into the computer (Getting nS > accuracy without wiring the probes together seems problematic...) Is this even possible with normal PC OS (Windows, Linux or Mac OS X)? Not even ns but 1us. > =A0 =A0* Fitting it all into the form factor and power limitations of a > USB port (ideally 100mA unpowered hub ~0.5W) > =A0 =A0* Keeping the assembled cost low Noise is one issue as Wouter mentioned. The other issue is safety. How do you clamp the input signal? If somebody measures a 24V signal, will the whole thing or the PC damaged? I assume you will not have galvanic isolation. -- = Xiaofan http://mcuee.blogspot.com -- = http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist