It works fine. Apparently the years it spent in storage just meant that it took some time being plugged in before it fully booted.
Fascinating. I'll have to keep that in mind.
Seems there's more to this than meets the eye. I ran through a full set of tests with it for maybe 45 minutes of use, got the full 8GS/s on one channel with no adapter (haven't seen the PP096 for sale anywhere, maybe it was included in the acquisition board after the manual was published?), got used to the controls, tested some functions, let it build up a few hundred thousand waveforms worth of persistence on the color graded display, but after I shut it down, it hasn't powered up since.
Went in to disassemble (lovely metal work), had some trouble pulling the power supply and I found out why... one of the PSU to board interconnects was slightly melted and singed - but no smell. Bad voltages on several rails direct from the power supply output, and when I popped the lid and took a look through the thermal camera, all of the power resistors in the power supply light up bright within seconds of turning on.
So there is real troubleshooting to be done, and the PSU is a bit cramped to try and work in, but the fact remains that briefly, it was just fine after exhibiting the same no-power-on failure. This gives me some confidence that despite how the rails read, they probably haven't cooked anything on the mainboard, since that probably would have shown when it was working. Still, chasing down the culprit could be tricky... I suppose the first order of business is checking continuity across main lines, but thankfully, the LC684 that has near identical hardware includes a full PSU schematic in the service manual bundle.
Probably a coming thread in the repair forum
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