>Interesting. Who makes the tester? > >Stuart How about a Ostby Barton-Pylon tester fixture (newark p/n 46f379_) with a HP 34970 multiplexed data acq. voltmeter. This is a system I set up for someone else, but it does what you're talking about. Test probes by IDI. You can also use different measurement tools: DSO/logic analyzer and add stimulus with custom gear. Phil