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I once saw it listed in a catalague as made by Fluke, but that might well have been a misprint. I bought one when it was current, and I love it. For those who've never used one, it's a handheld instrument whcih combines a continuity/diode tester, a 3-channel 100MHx logic analuyser and something called 'investigate mode'. The last is the most useful of the lot. You have one probe and a ground lead. Touch the probe on a point in the circuit, the instrument displays the average voltage at that point (good for checking PSUs), the frequency (counting theshold crossings per second, I guess), for checking the master clock, and has a couple of LEDs that act as a normal logic probe. Hit a button and it records the logic-level waveform (high/low/undefined) at that point. It's that last part that makes it much more useful than a normal logic probe. For example, I had a 9820 calculator on the bench, this is a bit-serial design. Running a logic probe along the outputs of the M (memory address) register, which is a 16 bit shift register made up of 4 off 4 bit chips showed that the top 4 bits were changing, all the rest were stuck low (it's loaded from the MSB end). OK, obvious, change the snecond-from-top chip... Alas the fault was still there. The LogicDart showed me that the timing of the outputs of the top chip was crazy with pulse widths equal to half the clock frequency. Therefore the second-from-top chip was working correctly, its input was always low on at the active clock edge. Changed the top chip. the machine sprang to life. What I'll do when the LogicDart fails I don't know. There's nothing available now that comes close to its functionality and convenience. There never was a sercvice manual available for it, and most of the logic is inside 2 ASICs anyway (therre's also an 80188 CPU, EPROM, RAM, display driver and a lot oa anloge stuff round the front end and PSU). Oh well... -tony